ystemsAdministrator 434 Greenville Drive, Baltimore Maryland, USA Home phone: (410) 567- 559 Fax: (410) 543- 5567 Cellphone: 8579870678 davidgates@yahoo.com |
|
Objective Aspiring for a position as a Senior Network/Systems Administrator that will let me utilize my management skills and extensive administration experience.
I have extensive experience with multiple UNIX-based operating systems with an emphasis on Solaris, Linux, FreeBSD, Cisco/Foundry/Force10 networking hardware and others. I am an expert in using Perl as well as C/C++ programming. I like to study new concepts and systems and I’m open to new ideas. I can work individually or be in a group. Technical Experience Operating Systems: · Linux · BSD (FreeBSD) · Desktop support of Windows 95/98/NT/2000/XP/Vista Networking: · Extensive knowledge in TCP/IP, UDP, ICMP · DHCP · SNMP · IPv6 · Load Balancing, custom balancers, BigIP’s F5 · MRTG, Cricket Security: · LAN/WAN security, VPN · Firewalls (Juniper Netscreen, IPFilter) · KAME IPSEC · Encryption (PGP, GnuPG, SSL) · SSH (SSH v1, v2 and OpenSSH) · Kerberos 5 (Heimdal) · S/Key/OPIE Software: · POP, IMAP, IMAPS · PPP (FreeBSD Kernel PPP) · SMTP (Postfix, QMail, Sendmail, procmail, majordomo, listserv, mhonarc) · X Window System (configuring servers, desktops, application servers, XDM) Database Administration: · Maintenance and replicating in MySQL · Limited/older experience with Oracle / Sybase Programming/Scripting: · Automation and maintenance tasks tasks · Perl5 · Shell scripting Hardware: · Cisco routers/switches/terminal servers · Cyclades and Lantronix terminal servers · F5 BigIP’s · Lots of co-location facility experience, large server installations, racking, power management, etc Work History Jan 2006-Present
Job Description: Member of a system administration team that is responsible for a farm of servers in 2 data centers that run MySQL, Linux and Apache. Our network serves over millions of page views to millions of visitors on daily basis. March 200-December 2006 Job Description: · Extensive documentation and planning for all Big Systems, Inc. business. Responsible for company-wide systems and network security · Handled all equipment negotiations and purchasing · Always on call |
Wednesday, December 23, 2009
RESUME MODEL - 3
RESUME MODEL - 2
Sam Bravo,
1234, Bright Drive,
Carlisle, MA 5775,
(123)-456 4377.
Objective:
Aspire to join a reputed company to perform my best abilities as a Windows System Administrator.
Education and Certification:
- Microsoft, Novell, and Oracle Certified
- BS Computer Science, New York University, NY (1996)
Work History:
Wildwood Association Inc., Adrian, MI (2004 - Present)
Systems Administrator
Tom Y Inc., Minneapolis, MN(1997 - 2004)
Junior System Administrator
Duties Performed:
- Installed software, patching, upgrading and maintenance of operating system.
- Installed, upgraded and maintenance of server hardware components as per requirement.
- Responsible for web services administration.
- Installed complex hardware and software and upgrades to ensure work is performed as per the company policy.
- Also responsible for supervision of backup and disaster recovery operations.
- Created and implemented recommendations to improve scalability and performance.
- Performed system startups and shutdowns.
Skills/Abilities/Knowledge:
- Good knowledge of hardware information such as CPU, Memory, Disk, Network, Bios.
- Strong knowledge of programming languages.
- Have good experience as Windows System Administrator.
- Excellent in MS Word, Excel, PowerPoint, Access, Outlook.
- Install complex software and hardware.
RESUME MODEL
CAREER OBJECTIVE:
To Serve the Organization as a System Administrator with dedication and commitment to get better results
INNOVATIVE:
Consistently analyze and improve technical capabilities related to the field of Information Technology there by increasing the efficiency and competitive with the fast growing Technologies.
TECHNICAL EXPERTISE:
Operating System: MS- DOS, Windows 9x, Windows XP, Windows 2000 Professional, Windows NT Server 4.0,Windows 2000/2003 Server.
BackOffice Administration: IIS, Proxy Server 2.0, Lotus Notes, Cluster, SAN
Packages: MS- Office 2000, MS-Project, MS Outlook, Outlook Express 2003
Mail Server: Exchange Server 5.5
Database: SQL 2000
Languages: C, C++
Deployment Solution: Altiris Deployment/Notification Server 6.0
Hardware
Platforms: Intel and AMD Chipsets
Assembling, installation and troubleshooting of servers (Dell/Compaq/HP)
EDUCATIONAL QUALIFICATION: Diploma in Computer Science & Engg.
CERTIFICATIONS:
* Microsoft Certified Professional (MCP) on Windows 2000
* Microsoft Certified System Administrator (MCSA) on Windows 2000
* Microsoft Certified System Engineer (MCSE) on Windows 2000
EXPERIENCE SUMMARY:
More than 5+ years of experience in IT Infrastructure Management. Currently supporting more than 1500 Windows NT/2000/2003 servers in US region for Fidelity. I have industry certifications like MCSE 2000 and MCSA.
Extensive experience on Server Configuration - Microsoft Windows NT Ver 4.0 and Windows 2000/2003. At present working for Fidelity Business Services Pvt Ltd as Systems Engineer
ONSITE EXPERIENCE:
Implementation of Windows 2003 Active Directory for BG Group client at Thames Valley Park UK for 3 months from (2nd April 2004 – 4th June 2004).
Designing monitoring solution for Exchange 2003 for BG Group at Thames Valley Park UK for 1 week from (26th Nov 2004 – 3rd Dec 2004)
S.No/ Company Name/ Designation/ Exp
From To
01 Fidelity Business Services India Pvt Ltd
Embassy Golf Links Business Park
Off Intermediate Ring Road
Bangalore, Karnataka – 560071
Phone: +91 080 56916000
Systems Engineer April 2005 Till Date
02 Accenture Services Pvt Ltd
RMZ Futura II
148/1, Bilekahalli Village
Bannerghatta Main Road
Bangalore -560076
Phone: +91 080 51387956
Senior System
Administrator 2
Years May
2003 April
2005
03 I2 Technologies
No.11, Divyasree Chambers
Langford Road
Bangalore 560 007
Phone: +91 080 2078000
System Administrator 2.9 Years
July
2000
April
2003
Experience Details:
1) Organization: Fidelity Business Services India Pvt Ltd
Duration: April 2005 till Date
Designation: Systems Engineer
Company Profile: Edward C. Johnson 2d founded Fidelity Investments in Boston in 1946 as Fidelity Management and Research Company (FMR Co).
Fidelity has over 50 years' experience and is the world's largest fund management company, looking after over US$1.2 trillion for 20 million investors worldwide.
Fidelity Information Systems Company India Pvt. Ltd., is located in Gurgaon (New Delhi) and Bangalore, and delivers technology solutions in support of U.S. business initiatives to enhance Fidelity's investment products and services
Job Role: Team lead for Offshore Enterprise Integrated Systems management (EISM) group
Responsibilities and Nature of Job:
Roles:
* Managing technical support team which is responsible for infrastructure services on Microsoft Windows technology
* Creating standard server build
* Updating servers with latest service packs and hot fixes.
* Troubleshooting Active Directory replication problems.
* Creating standard process for group policy deployment
* Active Directory users and groups management.
* Implementation and administration of DNS, DHCP and WINS
* Distribute packages via Altiris server across all the desktops and servers
* Review and remediate software distribution failures and to eliminate the problems that causes those failures.
* Design and implement a mechanism for handing on-off technical issues to other technical teams for resolution.
* Creating standard Net-backup policies and taking back-up of the servers. Restoring the data as per the customer request
* Preparing monthly work status report and updating technology specific documents
* Remote administration of servers for any problem across Fidelity offices related to Microsoft Windows operating system.
2) Organization: Accenture Services Pvt Ltd
Duration: May 2003 till April 2005
Designation: Senior Software Engineer
Company Profile: Accenture is a global management consulting, technology services and outsourcing company. Committed to delivering innovation, Accenture collaborates with its clients to help them become high-performance businesses and governments. With deep industry and business process expertise, broad global resources and a proven track record, Accenture can mobilize the right people, skills, and technologies to help clients improve their performance.
Job Role: Technical Support analyst
Responsibilities and Nature of Job:
Roles:
* Technical support of Operating System (Windows NT/2000)
* Monitoring servers using BMC patrol Express
* Backup Management, Reporting and Recovery
* Disaster Recovery
* Virus Protection and Eradication
* Maintenance of MS Exchange Environment
* Configuring and troubleshooting Microsoft Outlook and Outlook express.
* Provision of Internet Access and Management of Web marshal.
* Support for RAS and ACE servers and provision of user assistance out of UK office hours
* Analysis of Security Alerts and Implementation of Recommendations Third-party middleware and database software
* Implementing and troubleshooting Cluster and SAN.
* Call Management using Peregrine Service Center Tool.
Additional Responsibilities:
* Selected based on performance to join the UK project implementation team for BG Group (Technology Transformation Programme) TTP 2.
Job Scope:
* Implementation of Windows 2003 domain.
* Migrating User accounts from windows NT to windows 2003 domain
* Implementation of Altiris Deployment Server 6.0
* Implementation of Veritas Netbackup 5.0
* Implementation of BMC patrol enterprise manager 4.5
* Implementation of Quest AD tool sets – (Active Roles, Quest Reporter, Quest Restore and Spotlight on AD)
* Implementation of Netapps Filer (NAS) – FAS 270 and FAS 940
* Documentation of the product implementation.
* Trained members of BG Helpdesk
Complete project was implemented at BG head office, located at United Kingdom.
Address: Berkshire, United Kingdom (UK).
Project Duration:
3 Months (2nd April 2004 – 4th June 2004)
Training attended for implementing the Project:
CIFS Administration at London, UK
BMC Patrol starter at London, UK
Quest AD tool Sets at Warwick, UK
3) Organization: i2 Technologies Software Pvt Ltd
Duration: July 2000 till April 2003
Company Profile: i2, a billion dollar company, has the only B2B solution that incorporates a complete supply chain model, marketplace-to-marketplace support and rich content management capabilities.
Job Role: As a System administrator, I was responsible for Installing, configuring and troubleshooting Desktops, Laptops and Servers.
Responsibilities and nature of Job at i2 Technologies:
* Configuring and troubleshooting desktops, laptops and servers.
* Handle and troubleshoot operating system installations, software installations such as MS Office, PC Anywhere, Anti-virus software, Internet Information Server, Personal Web Server, and Lotus notes 5.08 Client Configuration. Setting up Remote Access Service for Lotus Notes Client users.
* Installation, configuration and testing of SCSI device such as hard drives, backup tape drives.
* Implementing RAID 1 and RAID 5 on mission critical servers such as domain controllers and file servers.
* Installation & maintenance of Windows NT & 2000 DNS, DDNS, DHCP and WINS Servers for the i2 DOMAIN.
* Administration and Maintenance of Windows based network of over 500
workstations and 240 Servers (Dell Servers -Power Edge 300,2400,4300,4400,6450 and Compaq Servers -1800R, ML350, 6500R, 8500R) running Windows NT 4.0/2000 operating systems.
* Worked as a Technical Lead to fully consolidate and migrate i2 NT Domain to a
Single mixed mode Windows 2000 Active Directory Domain.
* Implementing and administration Active Directory services, replication, Trust Relationship and enforcing Domain wide Group Policies.
* Administering Exchange server 5.5, MS Proxy server 2.0 and IIS.
* Remote Administration using terminal service, VNC, PCAnywhere and Damware.
Played a key role for setting up Internet Data-Centre (IDC) in Khanijabhavan for i2.
LANGUAGES KNOWN: English, Hindi, Urdu, Kannada and Marathi.
EXTRA CURRICULAR ACTIVITIES: Chess, Cricket, Reading Novels and Magazines
Reference:
Upon request
I here by declare that all the information provided is true to the best of my knowledge.
To Serve the Organization as a System Administrator with dedication and commitment to get better results
INNOVATIVE:
Consistently analyze and improve technical capabilities related to the field of Information Technology there by increasing the efficiency and competitive with the fast growing Technologies.
TECHNICAL EXPERTISE:
Operating System: MS- DOS, Windows 9x, Windows XP, Windows 2000 Professional, Windows NT Server 4.0,Windows 2000/2003 Server.
BackOffice Administration: IIS, Proxy Server 2.0, Lotus Notes, Cluster, SAN
Packages: MS- Office 2000, MS-Project, MS Outlook, Outlook Express 2003
Mail Server: Exchange Server 5.5
Database: SQL 2000
Languages: C, C++
Deployment Solution: Altiris Deployment/Notification Server 6.0
Hardware
Platforms: Intel and AMD Chipsets
Assembling, installation and troubleshooting of servers (Dell/Compaq/HP)
EDUCATIONAL QUALIFICATION: Diploma in Computer Science & Engg.
CERTIFICATIONS:
* Microsoft Certified Professional (MCP) on Windows 2000
* Microsoft Certified System Administrator (MCSA) on Windows 2000
* Microsoft Certified System Engineer (MCSE) on Windows 2000
EXPERIENCE SUMMARY:
More than 5+ years of experience in IT Infrastructure Management. Currently supporting more than 1500 Windows NT/2000/2003 servers in US region for Fidelity. I have industry certifications like MCSE 2000 and MCSA.
Extensive experience on Server Configuration - Microsoft Windows NT Ver 4.0 and Windows 2000/2003. At present working for Fidelity Business Services Pvt Ltd as Systems Engineer
ONSITE EXPERIENCE:
Implementation of Windows 2003 Active Directory for BG Group client at Thames Valley Park UK for 3 months from (2nd April 2004 – 4th June 2004).
Designing monitoring solution for Exchange 2003 for BG Group at Thames Valley Park UK for 1 week from (26th Nov 2004 – 3rd Dec 2004)
S.No/ Company Name/ Designation/ Exp
From To
01 Fidelity Business Services India Pvt Ltd
Embassy Golf Links Business Park
Off Intermediate Ring Road
Bangalore, Karnataka – 560071
Phone: +91 080 56916000
Systems Engineer April 2005 Till Date
02 Accenture Services Pvt Ltd
RMZ Futura II
148/1, Bilekahalli Village
Bannerghatta Main Road
Bangalore -560076
Phone: +91 080 51387956
Senior System
Administrator 2
Years May
2003 April
2005
03 I2 Technologies
No.11, Divyasree Chambers
Langford Road
Bangalore 560 007
Phone: +91 080 2078000
System Administrator 2.9 Years
July
2000
April
2003
Experience Details:
1) Organization: Fidelity Business Services India Pvt Ltd
Duration: April 2005 till Date
Designation: Systems Engineer
Company Profile: Edward C. Johnson 2d founded Fidelity Investments in Boston in 1946 as Fidelity Management and Research Company (FMR Co).
Fidelity has over 50 years' experience and is the world's largest fund management company, looking after over US$1.2 trillion for 20 million investors worldwide.
Fidelity Information Systems Company India Pvt. Ltd., is located in Gurgaon (New Delhi) and Bangalore, and delivers technology solutions in support of U.S. business initiatives to enhance Fidelity's investment products and services
Job Role: Team lead for Offshore Enterprise Integrated Systems management (EISM) group
Responsibilities and Nature of Job:
Roles:
* Managing technical support team which is responsible for infrastructure services on Microsoft Windows technology
* Creating standard server build
* Updating servers with latest service packs and hot fixes.
* Troubleshooting Active Directory replication problems.
* Creating standard process for group policy deployment
* Active Directory users and groups management.
* Implementation and administration of DNS, DHCP and WINS
* Distribute packages via Altiris server across all the desktops and servers
* Review and remediate software distribution failures and to eliminate the problems that causes those failures.
* Design and implement a mechanism for handing on-off technical issues to other technical teams for resolution.
* Creating standard Net-backup policies and taking back-up of the servers. Restoring the data as per the customer request
* Preparing monthly work status report and updating technology specific documents
* Remote administration of servers for any problem across Fidelity offices related to Microsoft Windows operating system.
2) Organization: Accenture Services Pvt Ltd
Duration: May 2003 till April 2005
Designation: Senior Software Engineer
Company Profile: Accenture is a global management consulting, technology services and outsourcing company. Committed to delivering innovation, Accenture collaborates with its clients to help them become high-performance businesses and governments. With deep industry and business process expertise, broad global resources and a proven track record, Accenture can mobilize the right people, skills, and technologies to help clients improve their performance.
Job Role: Technical Support analyst
Responsibilities and Nature of Job:
Roles:
* Technical support of Operating System (Windows NT/2000)
* Monitoring servers using BMC patrol Express
* Backup Management, Reporting and Recovery
* Disaster Recovery
* Virus Protection and Eradication
* Maintenance of MS Exchange Environment
* Configuring and troubleshooting Microsoft Outlook and Outlook express.
* Provision of Internet Access and Management of Web marshal.
* Support for RAS and ACE servers and provision of user assistance out of UK office hours
* Analysis of Security Alerts and Implementation of Recommendations Third-party middleware and database software
* Implementing and troubleshooting Cluster and SAN.
* Call Management using Peregrine Service Center Tool.
Additional Responsibilities:
* Selected based on performance to join the UK project implementation team for BG Group (Technology Transformation Programme) TTP 2.
Job Scope:
* Implementation of Windows 2003 domain.
* Migrating User accounts from windows NT to windows 2003 domain
* Implementation of Altiris Deployment Server 6.0
* Implementation of Veritas Netbackup 5.0
* Implementation of BMC patrol enterprise manager 4.5
* Implementation of Quest AD tool sets – (Active Roles, Quest Reporter, Quest Restore and Spotlight on AD)
* Implementation of Netapps Filer (NAS) – FAS 270 and FAS 940
* Documentation of the product implementation.
* Trained members of BG Helpdesk
Complete project was implemented at BG head office, located at United Kingdom.
Address: Berkshire, United Kingdom (UK).
Project Duration:
3 Months (2nd April 2004 – 4th June 2004)
Training attended for implementing the Project:
CIFS Administration at London, UK
BMC Patrol starter at London, UK
Quest AD tool Sets at Warwick, UK
3) Organization: i2 Technologies Software Pvt Ltd
Duration: July 2000 till April 2003
Company Profile: i2, a billion dollar company, has the only B2B solution that incorporates a complete supply chain model, marketplace-to-marketplace support and rich content management capabilities.
Job Role: As a System administrator, I was responsible for Installing, configuring and troubleshooting Desktops, Laptops and Servers.
Responsibilities and nature of Job at i2 Technologies:
* Configuring and troubleshooting desktops, laptops and servers.
* Handle and troubleshoot operating system installations, software installations such as MS Office, PC Anywhere, Anti-virus software, Internet Information Server, Personal Web Server, and Lotus notes 5.08 Client Configuration. Setting up Remote Access Service for Lotus Notes Client users.
* Installation, configuration and testing of SCSI device such as hard drives, backup tape drives.
* Implementing RAID 1 and RAID 5 on mission critical servers such as domain controllers and file servers.
* Installation & maintenance of Windows NT & 2000 DNS, DDNS, DHCP and WINS Servers for the i2 DOMAIN.
* Administration and Maintenance of Windows based network of over 500
workstations and 240 Servers (Dell Servers -Power Edge 300,2400,4300,4400,6450 and Compaq Servers -1800R, ML350, 6500R, 8500R) running Windows NT 4.0/2000 operating systems.
* Worked as a Technical Lead to fully consolidate and migrate i2 NT Domain to a
Single mixed mode Windows 2000 Active Directory Domain.
* Implementing and administration Active Directory services, replication, Trust Relationship and enforcing Domain wide Group Policies.
* Administering Exchange server 5.5, MS Proxy server 2.0 and IIS.
* Remote Administration using terminal service, VNC, PCAnywhere and Damware.
Played a key role for setting up Internet Data-Centre (IDC) in Khanijabhavan for i2.
LANGUAGES KNOWN: English, Hindi, Urdu, Kannada and Marathi.
EXTRA CURRICULAR ACTIVITIES: Chess, Cricket, Reading Novels and Magazines
Reference:
Upon request
I here by declare that all the information provided is true to the best of my knowledge.
Tuesday, December 22, 2009
WAP
WAP
(1) (Wireless Access Point) See access point.
(2) (Wired Access Point) See wired access point.
(3) (Wireless Application Protocol) A standard for providing cellphones, pagers and other handhelds with secure access to e-mail and text-based Web pages. Introduced in 1997 by Phone.com, Ericsson, Motorola and Nokia, WAP provides an environment for wireless applications that includes a wireless version of TCP/IP and a framework for telephony integration such as call control and phone book access. Supporting keypad and voice recognition, WAP is independent of the air interface and runs over all major wireless networks. It is also device independent and can be used in any mobile device.
WML, WMLScript and XHTML
WAP introduced the Wireless Markup Language (WML), a streamlined version of HTML, and WMLScript, a compact form of JavaScript that runs in limited memory. WML later evolved into mobile versions of XHTML, which, along with all WAP protocols, are governed by the Open Mobile Alliance, the successor to the WAP Forum (see OMA).
WAP and SMS = MMS
The multimedia messaging system (MMS) uses both the SMS text messaging and WAP protocols to transmit graphics, audio and video to cellphones (see MMS). See WTLS, XHTML, HDML, Openwave and i-mode.
Openwave Applications
(1) (Wireless Access Point) See access point.
(2) (Wired Access Point) See wired access point.
(3) (Wireless Application Protocol) A standard for providing cellphones, pagers and other handhelds with secure access to e-mail and text-based Web pages. Introduced in 1997 by Phone.com, Ericsson, Motorola and Nokia, WAP provides an environment for wireless applications that includes a wireless version of TCP/IP and a framework for telephony integration such as call control and phone book access. Supporting keypad and voice recognition, WAP is independent of the air interface and runs over all major wireless networks. It is also device independent and can be used in any mobile device.
WML, WMLScript and XHTML
WAP introduced the Wireless Markup Language (WML), a streamlined version of HTML, and WMLScript, a compact form of JavaScript that runs in limited memory. WML later evolved into mobile versions of XHTML, which, along with all WAP protocols, are governed by the Open Mobile Alliance, the successor to the WAP Forum (see OMA).
WAP and SMS = MMS
The multimedia messaging system (MMS) uses both the SMS text messaging and WAP protocols to transmit graphics, audio and video to cellphones (see MMS). See WTLS, XHTML, HDML, Openwave and i-mode.
Openwave Applications
Openwave has been a major contributor to the development of smartphone interfaces. These are examples of earlier applications when cellphone screens were exceptionally tiny. (Image courtesy of Openwave Systems Inc.)
Windows Home Server
Windows Home Server
A consumer version of Windows Server 2003 designed for homes with multiple PCs. Introduced in late 2007, it offers a variety of centralized services, including backup, file sharing, printer sharing, security monitoring as well as remote administration. Although based on the enterprise version, Windows Home Server (WHS) provides a simpler user interface for family members.
Centralized Backup and File Sharing
The primary advantages of Windows Home Server are centralized backup and storage. WHS provides automated backup of data for all machines in the network, and it can restore the entire contents of the disk of a failed machine. In order to use WHS, every client in the network must install WHS Connector software.
As more homes are networked, images and videos become duplicated in two or more computers, or some data are stored in one computer while the rest resides in another. Having all sharable data in a centralized location makes it easy for family members to find what they need, and files and folders can be shared with any user in the network. In addition, they can be accessed via any PC connected to the Internet because WHS can be set up as a Web server that faces the public Internet. See Windows Server 2003.
A consumer version of Windows Server 2003 designed for homes with multiple PCs. Introduced in late 2007, it offers a variety of centralized services, including backup, file sharing, printer sharing, security monitoring as well as remote administration. Although based on the enterprise version, Windows Home Server (WHS) provides a simpler user interface for family members.
Centralized Backup and File Sharing
The primary advantages of Windows Home Server are centralized backup and storage. WHS provides automated backup of data for all machines in the network, and it can restore the entire contents of the disk of a failed machine. In order to use WHS, every client in the network must install WHS Connector software.
As more homes are networked, images and videos become duplicated in two or more computers, or some data are stored in one computer while the rest resides in another. Having all sharable data in a centralized location makes it easy for family members to find what they need, and files and folders can be shared with any user in the network. In addition, they can be accessed via any PC connected to the Internet because WHS can be set up as a Web server that faces the public Internet. See Windows Server 2003.
Windows HPC Server
Windows HPC Server
A high-performance computing (HPC) version of Windows. Windows HPC Server 2008 is a subset of Windows Server 2008 that is designed for parallel computing (clustering). Windows HPC includes failover capabilities as well as the MPI protocol for passing messages between computers and RDMA, which enables direct memory access from one computer to another. See MPI, RDMA, clustering and Windows Server 2008.
A high-performance computing (HPC) version of Windows. Windows HPC Server 2008 is a subset of Windows Server 2008 that is designed for parallel computing (clustering). Windows HPC includes failover capabilities as well as the MPI protocol for passing messages between computers and RDMA, which enables direct memory access from one computer to another. See MPI, RDMA, clustering and Windows Server 2008.
Windows Server 2008
Windows Server 2008
The latest enterprise server version of Windows that supersedes Windows Server 2003. Supporting 128-bit IPv6 addressing for the Internet and BitLocker drive encryption, Windows Server 2008 added numerous security, network and system administration enhancements.
Integrated Virtualization
One of Windows Server 2008's main features, built into all but the Web server and Itanium versions, is "Hyper-V Server." Hyper-V provides a virtual machine capability that eliminates the need for a third-party product such as VMware. The OS is available without Hyper-V, which can be added later.
A Slimmer Installation Option
A unique feature of Windows Server 2008 is its "Server Core" option, which installs essential operating system components without the user interface. It is used for dedicated servers such as an Active Directory, DNS, DHCP, print or Web server.
Originally code named "Longhorn," Windows Server 2008 was officially named in May of 2007 and released, of course, in 2008. See Windows HPC Server, BitLocker, IPv6 and Windows Server 2003.
The latest enterprise server version of Windows that supersedes Windows Server 2003. Supporting 128-bit IPv6 addressing for the Internet and BitLocker drive encryption, Windows Server 2008 added numerous security, network and system administration enhancements.
Integrated Virtualization
One of Windows Server 2008's main features, built into all but the Web server and Itanium versions, is "Hyper-V Server." Hyper-V provides a virtual machine capability that eliminates the need for a third-party product such as VMware. The OS is available without Hyper-V, which can be added later.
A Slimmer Installation Option
A unique feature of Windows Server 2008 is its "Server Core" option, which installs essential operating system components without the user interface. It is used for dedicated servers such as an Active Directory, DNS, DHCP, print or Web server.
Originally code named "Longhorn," Windows Server 2008 was officially named in May of 2007 and released, of course, in 2008. See Windows HPC Server, BitLocker, IPv6 and Windows Server 2003.
Edition of SMP
Windows Server 2008 Support RAM
With or Without Hyper-V
Virtualization
32-bit Standard 4-way 4GB
64-bit Standard 4-way 32GB
32-bit Enterprise 8-way 64GB
64-bit Enterprise 8-way 2TB
32-bit DataCenter 32-way 64GB
64-bit DataCenter 64-way 2TB
Without Hyper-V
Virtualization
32-bit Web Server 4-way 4GB
64-bit Web Server 4-way 32GB
64-bit Itanium
Version 64-way 2TB
Windows Server 2003
Windows Server 2003
The .NET version of the Windows 2000 server operating system. Introduced in the spring of 2003, it was originally known as .NET Server 2003. Similar to the Windows 2000 offerings, Windows Server 2003 is available in several versions. The Enterprise and Datacenter Editions are geared for mission critical applications with support for clustering, failover and load balancing. They are also available in 64-bit versions for Intel's IA-64 architecture. The Web Edition is designed for hosting a Web site. See Windows Home Server, Windows Server 2008 and .NET Enterprise Server.
The .NET version of the Windows 2000 server operating system. Introduced in the spring of 2003, it was originally known as .NET Server 2003. Similar to the Windows 2000 offerings, Windows Server 2003 is available in several versions. The Enterprise and Datacenter Editions are geared for mission critical applications with support for clustering, failover and load balancing. They are also available in 64-bit versions for Intel's IA-64 architecture. The Web Edition is designed for hosting a Web site. See Windows Home Server, Windows Server 2008 and .NET Enterprise Server.
Edition of SMP
Windows Server 2003 Support RAM
Standard 2-way 4GB
Web Server 2-way 2GB
32-bit Enterprise 8-way 32GB
64-bit Enterprise 8-way 64GB
32-bit DataCenter 32-way 64GB
64-bit DataCenter 32-way 128GB
Winchester Disk
Winchester disk
An early removable disk drive from IBM that put the heads and platters (disks) in a sealed unit for greater speed. Before the Winchester architecture, removable disks were like removable disks today, in which the read/write heads remain in the drive and make contact with the platter after the cartridge is inserted.
Introduced in 1973 as the model 3340, the drive had one permanent and one removable spindle, each holding 30MB. The "30-30" storage capacities led to the Winchester nickname after the Winchester 30-30 rifle. The term later referred to all fixed hard disks because the heads and platters are always encased in the same, sealed unit. See also Winchester.
An early removable disk drive from IBM that put the heads and platters (disks) in a sealed unit for greater speed. Before the Winchester architecture, removable disks were like removable disks today, in which the read/write heads remain in the drive and make contact with the platter after the cartridge is inserted.
Introduced in 1973 as the model 3340, the drive had one permanent and one removable spindle, each holding 30MB. The "30-30" storage capacities led to the Winchester nickname after the Winchester 30-30 rifle. The term later referred to all fixed hard disks because the heads and platters are always encased in the same, sealed unit. See also Winchester.
An early removable disk drive from IBM that put the heads and platters (disks) in a sealed unit for greater speed. Before the Winchester architecture, removable disks were like removable disks today, in which the read/write heads remain in the drive and make contact with the platter after the cartridge is inserted.
Introduced in 1973 as the model 3340, the drive had one permanent and one removable spindle, each holding 30MB. The "30-30" storage capacities led to the Winchester nickname after the Winchester 30-30 rifle. The term later referred to all fixed hard disks because the heads and platters are always encased in the same, sealed unit. See also Winchester.
An early removable disk drive from IBM that put the heads and platters (disks) in a sealed unit for greater speed. Before the Winchester architecture, removable disks were like removable disks today, in which the read/write heads remain in the drive and make contact with the platter after the cartridge is inserted.
Introduced in 1973 as the model 3340, the drive had one permanent and one removable spindle, each holding 30MB. The "30-30" storage capacities led to the Winchester nickname after the Winchester 30-30 rifle. The term later referred to all fixed hard disks because the heads and platters are always encased in the same, sealed unit. See also Winchester.
WIRELESS LAN
wireless LAN
(wireless Local Area Network) A communications network that provides connectivity to wireless devices within a limited geographic area. "Wi-Fi" is the universal standard for wireless networks and is the wireless equivalent of wired Ethernet networks. In the office, Wi-Fi networks are adjuncts to the wired networks. At home, a Wi-Fi network can serve as the only network since all laptops and many printers come with Wi-Fi built in, and it can be added to desktop computers.
Wi-Fi LANs do not require line of sight between sender and receiver. Wireless base stations, called "access points," have antennas that transmit and receive a radio frequency within a range of 30 to 150 feet through walls and other non-metal barriers.
Machines Can Be Retrofitted
Old laptops can be upgraded with Wi-Fi adapters via a PC Card slot or USB, and desktop computers in distant rooms can be made wireless by plugging a wireless adapter into a USB port.
The Wireless Router - All In One
A wireless router is the foundation network component in most homes and small offices, combining wired and wireless in one unit. It is an access point, switch and router. The access point is the wireless base station, the switch interconnects four wired and any number of wireless devices, and the router forwards Internet traffic to the modem, which is attached to the cable company's coaxial cable or the telephone company's DSL phone line.
Since all wireless and wired computers are interconnected, they can exchange data with each other for backup and file sharing. For technical details of the wireless standards, see 802.11. See hotspot, router, LAN switch, wireless broadband and WPAN.
(wireless Local Area Network) A communications network that provides connectivity to wireless devices within a limited geographic area. "Wi-Fi" is the universal standard for wireless networks and is the wireless equivalent of wired Ethernet networks. In the office, Wi-Fi networks are adjuncts to the wired networks. At home, a Wi-Fi network can serve as the only network since all laptops and many printers come with Wi-Fi built in, and it can be added to desktop computers.
Wi-Fi LANs do not require line of sight between sender and receiver. Wireless base stations, called "access points," have antennas that transmit and receive a radio frequency within a range of 30 to 150 feet through walls and other non-metal barriers.
Machines Can Be Retrofitted
Old laptops can be upgraded with Wi-Fi adapters via a PC Card slot or USB, and desktop computers in distant rooms can be made wireless by plugging a wireless adapter into a USB port.
The Wireless Router - All In One
A wireless router is the foundation network component in most homes and small offices, combining wired and wireless in one unit. It is an access point, switch and router. The access point is the wireless base station, the switch interconnects four wired and any number of wireless devices, and the router forwards Internet traffic to the modem, which is attached to the cable company's coaxial cable or the telephone company's DSL phone line.
Since all wireless and wired computers are interconnected, they can exchange data with each other for backup and file sharing. For technical details of the wireless standards, see 802.11. See hotspot, router, LAN switch, wireless broadband and WPAN.
NetBIOS
NetBIOS
The original networking protocol for DOS and Windows PCs. NetBIOS packets did not contain a network address and were not easily routable between networks. As a result, the interface to NetBIOS and the transport part of NetBIOS were later separated so that NetBIOS applications could use routable protocols such as TCP/IP and SPX/IPX. The programming interface (API) retained the NetBIOS name, while the transport protocol was renamed NetBEUI (pronounced "net-boo-ee").
Name Resolution
Today, NetBIOS is used to support legacy NetBIOS applications but is also widely used for NetBIOS name resolution. Since NetBIOS was the first major standard for PC networks, computers were named according to the NetBIOS format, which identifies a machine by a unique 15-character name. NetBIOS machines periodically broadcast their names over the network so that Network Neighborhood or My Network Places can catalog them.
Datagram and Session Modes
NetBIOS is generally defined as a session layer protocol in the protocol stack, supporting two modes: a fast Datagram mode that does not guarantee delivery and a Session mode that establishes a connection and guarantees delivery. See NBT, WINS and LMHOSTS file.
The original networking protocol for DOS and Windows PCs. NetBIOS packets did not contain a network address and were not easily routable between networks. As a result, the interface to NetBIOS and the transport part of NetBIOS were later separated so that NetBIOS applications could use routable protocols such as TCP/IP and SPX/IPX. The programming interface (API) retained the NetBIOS name, while the transport protocol was renamed NetBEUI (pronounced "net-boo-ee").
Name Resolution
Today, NetBIOS is used to support legacy NetBIOS applications but is also widely used for NetBIOS name resolution. Since NetBIOS was the first major standard for PC networks, computers were named according to the NetBIOS format, which identifies a machine by a unique 15-character name. NetBIOS machines periodically broadcast their names over the network so that Network Neighborhood or My Network Places can catalog them.
Datagram and Session Modes
NetBIOS is generally defined as a session layer protocol in the protocol stack, supporting two modes: a fast Datagram mode that does not guarantee delivery and a Session mode that establishes a connection and guarantees delivery. See NBT, WINS and LMHOSTS file.
WINDOWS
Windows
The most widely used operating system for desktop and laptop computers. Developed by Microsoft, Windows primarily runs on x86-based CPUs, although some versions run on Intel's Itanium CPUs. Windows provides a graphical user interface and desktop environment in which applications are displayed in resizable, movable windows on screen.
Windows comes in both client and server versions, all of which support networking, the difference being that the server versions are designed to be dedicated servers. The client versions of Windows may also share data over the network and can be configured to grant access to all or specific files only. Windows PCs are used to access a variety of servers on the network, including Windows servers, Unix, Linux and NetWare servers, as well as mainframes. See operating system.
Windows How to's
All the Windows "how to's" in this encyclopedia have a "Win" prefix in front of their name in order to group them together in the index; for example, Win Change window appearance and Win Finding files. For fundamentals on how to work with Windows, see Win abc's.
Following is a summary of Windows versions.
Windows NT Lineage (32 & 64 bit)
Windows 7 (2009) - MS Version 7.0
The current client version of Windows. See Windows 7.
Windows Vista (2006) - MS Version 6.0
The previous client version of Windows, which comes in several flavors (see Windows Vista). Windows Server 2008 is the server version (code named Longhorn Server). See Windows Server 2008.
Windows XP (2001) - MS Version 5.1
Windows XP was the previous version of Windows, available in Home and Professional versions, the latter adding more security and administrative capabilities. There were also versions of XP that ran on AMD's 64-bit CPUs and Intel's 64-bit Itaniums. See Windows XP.
Windows 2000 (2000) - MS Version 5.0
Windows 2000 is an updated version of Windows NT 4 for client and server. It added numerous enhancements including Plug and Play and Active Directory. Windows 2000 comes in one workstation version and three server versions. There are server versions that support AMD's 64-bit CPUs and Intel's 64-bit Itaniums. See Windows 2000.
Windows NT (1993) - MS Versions 3.1, 3.5, 4.0
Windows NT 3.1 was a completely new 32-bit OS with separate client and server versions. Introduced during the reign of Windows 3.1 and two years before Windows 95, it used the same Program Manager user interface as Windows 3.1, but provided greater stability. In 1996, Windows NT 4.0 switched to the Windows 95 Start menu and Taskbar interface, but did not include Plug and Play. NT Server gained significant market share, while NT Workstation (client version) was used by the professional user and did not impact the Windows 95/98 market. See Windows NT.
Windows 95 Lineage (32 bit)
Windows ME (2000) - MS Version 4.9
An upgrade to Windows 98. ME had a shorter boot time, but no longer could be booted into DOS only (DOS sessions could still be run in a Windows window). See Windows ME.
Windows 98 (1998) - MS Version 4.1
Windows 98 was an upgrade to Windows 95 that tightly integrated the Internet Explorer Web browser with the OS. In 1999, Windows 98 Second Edition fixed numerous bugs and upgraded its applications. See Windows 98 and Windows Second Edition.
Windows 95 (1995) - MS Version 4.0
Windows 95 was the first 32-bit Windows operating system and a major upgrade from Windows 3.1. It used an entirely different user interface that incorporated the now-common Start menu and Taskbar. It was also the first time the computer booted directly into Windows, rather than being loaded after booting up in DOS. See Windows 95.
Windows DOS Lineage (16 bit)
Windows 3.1 (1992) - MS Version 3.x
An upgrade to Windows 3.0 that provided a more stable and faster environment. It evolved into Windows for Workgroups Version 3.11, which added peer-to-peer networking and was the last 16-bit Windows version. See Windows 3.1.
Windows 3.0 (1990) - MS Version 3.x
The first popular version of Windows. It provided a new and colorful user interface that was far superior to earlier versions. The PC was still booted up in DOS, but Windows included a DOS extender that broke the one megabyte memory barrier, a major breakthrough for that time. Windows 3.0 was widely used to multitask DOS applications. See Windows 3.0.
Windows 2.0/286/386 (1987) - MS Version 2.0
Windows 2.0 introduced overlapping, resizable windows with more flexibility. Soon after, Windows/386 was released for Intel's 386 CPU, which could run multiple DOS applications simultaneously (Windows 2.0 was then renamed Windows/286). Windows was starting to become more useful, and a handful of companies adopted it as an operating environment. See Windows 2.0.
Windows 1.0 (1985) - MS Version 1.0
The first version of Windows introduced the "MS-DOS Executive," which was a DOS application that ran applications in side-by-side windows. It barely made a dent in the market. See Windows 1.0.
The most widely used operating system for desktop and laptop computers. Developed by Microsoft, Windows primarily runs on x86-based CPUs, although some versions run on Intel's Itanium CPUs. Windows provides a graphical user interface and desktop environment in which applications are displayed in resizable, movable windows on screen.
Windows comes in both client and server versions, all of which support networking, the difference being that the server versions are designed to be dedicated servers. The client versions of Windows may also share data over the network and can be configured to grant access to all or specific files only. Windows PCs are used to access a variety of servers on the network, including Windows servers, Unix, Linux and NetWare servers, as well as mainframes. See operating system.
Following is a summary of Windows versions.
Windows 7 (2009) - MS Version 7.0
The current client version of Windows. See Windows 7.
Windows Vista (2006) - MS Version 6.0
The previous client version of Windows, which comes in several flavors (see Windows Vista). Windows Server 2008 is the server version (code named Longhorn Server). See Windows Server 2008.
Windows XP (2001) - MS Version 5.1
Windows XP was the previous version of Windows, available in Home and Professional versions, the latter adding more security and administrative capabilities. There were also versions of XP that ran on AMD's 64-bit CPUs and Intel's 64-bit Itaniums. See Windows XP.
Windows 2000 (2000) - MS Version 5.0
Windows 2000 is an updated version of Windows NT 4 for client and server. It added numerous enhancements including Plug and Play and Active Directory. Windows 2000 comes in one workstation version and three server versions. There are server versions that support AMD's 64-bit CPUs and Intel's 64-bit Itaniums. See Windows 2000.
Windows NT (1993) - MS Versions 3.1, 3.5, 4.0
Windows NT 3.1 was a completely new 32-bit OS with separate client and server versions. Introduced during the reign of Windows 3.1 and two years before Windows 95, it used the same Program Manager user interface as Windows 3.1, but provided greater stability. In 1996, Windows NT 4.0 switched to the Windows 95 Start menu and Taskbar interface, but did not include Plug and Play. NT Server gained significant market share, while NT Workstation (client version) was used by the professional user and did not impact the Windows 95/98 market. See Windows NT.
Windows ME (2000) - MS Version 4.9
An upgrade to Windows 98. ME had a shorter boot time, but no longer could be booted into DOS only (DOS sessions could still be run in a Windows window). See Windows ME.
Windows 98 (1998) - MS Version 4.1
Windows 98 was an upgrade to Windows 95 that tightly integrated the Internet Explorer Web browser with the OS. In 1999, Windows 98 Second Edition fixed numerous bugs and upgraded its applications. See Windows 98 and Windows Second Edition.
Windows 95 (1995) - MS Version 4.0
Windows 95 was the first 32-bit Windows operating system and a major upgrade from Windows 3.1. It used an entirely different user interface that incorporated the now-common Start menu and Taskbar. It was also the first time the computer booted directly into Windows, rather than being loaded after booting up in DOS. See Windows 95.
Windows 3.1 (1992) - MS Version 3.x
An upgrade to Windows 3.0 that provided a more stable and faster environment. It evolved into Windows for Workgroups Version 3.11, which added peer-to-peer networking and was the last 16-bit Windows version. See Windows 3.1.
Windows 3.0 (1990) - MS Version 3.x
The first popular version of Windows. It provided a new and colorful user interface that was far superior to earlier versions. The PC was still booted up in DOS, but Windows included a DOS extender that broke the one megabyte memory barrier, a major breakthrough for that time. Windows 3.0 was widely used to multitask DOS applications. See Windows 3.0.
Windows 2.0/286/386 (1987) - MS Version 2.0
Windows 2.0 introduced overlapping, resizable windows with more flexibility. Soon after, Windows/386 was released for Intel's 386 CPU, which could run multiple DOS applications simultaneously (Windows 2.0 was then renamed Windows/286). Windows was starting to become more useful, and a handful of companies adopted it as an operating environment. See Windows 2.0.
Windows 1.0 (1985) - MS Version 1.0
The first version of Windows introduced the "MS-DOS Executive," which was a DOS application that ran applications in side-by-side windows. It barely made a dent in the market. See Windows 1.0.
Word
Windows Size Year Built-in
Version (bits) Intro Networking
NT Lineage
Windows Server 32/64 2008 yes
Windows Vista 32/64 2006 yes
Windows Server 32/64 2003 yes
Windows XP 32/64 2001 yes
Windows 2000 32 2000 yes
Windows NT 32 1993 yes
95 Lineage
Windows ME 32 2000 yes
Windows 98 32 1998 yes
Windows 95 32 1995 yes
DOS Lineage
WfW 3.1 16 1992 yes
Windows 3.1 16 1992 no
Windows 3.0 16 1990 no
Windows/386 16 1987 no
Windows 2.0 16 1987 no
Windows 1.0 16 1985 no
MS- SQL SERVER
Microsoft SQL Server
A relational DBMS from Microsoft that is a major component of the Windows Server System. It is Microsoft's high-end client/server database and is closely integrated with Microsoft Visual Studio and the Microsoft Office System. Numerous editions are available, including those for Enterprise, Developer, Workgroup and 64-bit platforms.
Common Code Roots
SQL Server was originally developed by Sybase and also sold by Microsoft for OS/2 and Windows NT. In 1992, Microsoft began development of its own version, but acknowledged Sybase as copyright holder of origin until 1994. Future revisions diverged in 1995 when Sybase renamed its product Adaptive Server Enterprise as a means of differentiation (see ASE).
A relational DBMS from Microsoft that is a major component of the Windows Server System. It is Microsoft's high-end client/server database and is closely integrated with Microsoft Visual Studio and the Microsoft Office System. Numerous editions are available, including those for Enterprise, Developer, Workgroup and 64-bit platforms.
Common Code Roots
SQL Server was originally developed by Sybase and also sold by Microsoft for OS/2 and Windows NT. In 1992, Microsoft began development of its own version, but acknowledged Sybase as copyright holder of origin until 1994. Future revisions diverged in 1995 when Sybase renamed its product Adaptive Server Enterprise as a means of differentiation (see ASE).
Unix commands
Unix commands
Unix was developed as a command line interface and has a much richer vocabulary than DOS, which followed 12 years later. Unix text may or may not be case sensitive, whereas DOS/Windows is not case sensitive. Following is a brief comparison of common Unix/Linux commands and their DOS/Windows counterparts:
Unix was developed as a command line interface and has a much richer vocabulary than DOS, which followed 12 years later. Unix text may or may not be case sensitive, whereas DOS/Windows is not case sensitive. Following is a brief comparison of common Unix/Linux commands and their DOS/Windows counterparts:
Unix/ DOS/
Command Linux Windows
List directory content ls dir
Copy a file cp copy
Delete a file rm del
Rename a file mv rename
Display contents cat type
Print a file lpr print
Check disk space df chkdsk
Change directory cd cd
Lotus Notes
Lotus Notes
Messaging and groupware software from IBM Lotus that was introduced in 1989 for OS/2 and later expanded to Windows, Mac, Unix, NetWare, AS/400 and S/390. Notes provides e-mail, document sharing, workflow, group discussions and calendaring and scheduling. It also accepts plug-ins for other functions.
The heart of Notes, and what makes it different from other groupware, is its document database. Everything, including mail and group discussions, are maintained in a Notes database, which can hold data fields, text, audio and video.
Synchronized Distributed Databases
Notes provides strong replication capability, which synchronizes databases distributed in multiple locations and to mobile users. The Notes Name & Address Book provides a central directory for all resources. Many applications have been built with Notes using its macro language and LotusScript, a Visual Basic-like programming language.
Notes Server Became Domino
In 1996, the Notes client was decoupled from the Notes server, which was renamed Domino. Domino is Internet compliant and can be accessed by a Web browser, converting Notes database contents into HTML pages on the fly. The Notes client also contains a browser, which can download Web pages and maintain them as Notes documents.
The Father of Groupware
Notes is often considered the father of groupware, because it was the first to popularize a development environment around groupware functions.
Messaging and groupware software from IBM Lotus that was introduced in 1989 for OS/2 and later expanded to Windows, Mac, Unix, NetWare, AS/400 and S/390. Notes provides e-mail, document sharing, workflow, group discussions and calendaring and scheduling. It also accepts plug-ins for other functions.
The heart of Notes, and what makes it different from other groupware, is its document database. Everything, including mail and group discussions, are maintained in a Notes database, which can hold data fields, text, audio and video.
Synchronized Distributed Databases
Notes provides strong replication capability, which synchronizes databases distributed in multiple locations and to mobile users. The Notes Name & Address Book provides a central directory for all resources. Many applications have been built with Notes using its macro language and LotusScript, a Visual Basic-like programming language.
Notes Server Became Domino
In 1996, the Notes client was decoupled from the Notes server, which was renamed Domino. Domino is Internet compliant and can be accessed by a Web browser, converting Notes database contents into HTML pages on the fly. The Notes client also contains a browser, which can download Web pages and maintain them as Notes documents.
The Father of Groupware
Notes is often considered the father of groupware, because it was the first to popularize a development environment around groupware functions.
blade server
blade server
blade server architecture that houses multiple server modules ("blades") in a single chassis. It is widely used in datacenters to save space and improve system management. Either self-standing or rack mounted, the chassis provides the power supply, and each blade has its own CPU, memory and hard disk. Redundant power supplies may be an option. Blade servers generally provide their own management systems and may include a network or storage switch. Contrast with blade PC.
Diskless Blades
With enterprise-class blade servers, disk storage is external, and the blades are diskless. This approach allows for more efficient failover because applications are not tied to specific hardware and a particular instance of the operating system. The blades are anonymous and interchangeable. See blade and processor area network.
A server architecture that houses multiple server modules ("blades") in a single chassis. It is widely used in datacenters to save space and improve system management. Either self-standing or rack mounted, the chassis provides the power supply, and each blade has its own CPU, memory and hard disk. Redundant power supplies may be an option. Blade servers generally provide their own management systems and may include a network or storage switch. Contrast with blade PC.
Diskless Blades
With enterprise-class blade servers, disk storage is external, and the blades are diskless. This approach allows for more efficient failover because applications are not tied to specific hardware and a particular instance of the operating system. The blades are anonymous and interchangeable. See blade and processor area network.
blade server architecture that houses multiple server modules ("blades") in a single chassis. It is widely used in datacenters to save space and improve system management. Either self-standing or rack mounted, the chassis provides the power supply, and each blade has its own CPU, memory and hard disk. Redundant power supplies may be an option. Blade servers generally provide their own management systems and may include a network or storage switch. Contrast with blade PC.
Diskless Blades
With enterprise-class blade servers, disk storage is external, and the blades are diskless. This approach allows for more efficient failover because applications are not tied to specific hardware and a particular instance of the operating system. The blades are anonymous and interchangeable. See blade and processor area network.
A server architecture that houses multiple server modules ("blades") in a single chassis. It is widely used in datacenters to save space and improve system management. Either self-standing or rack mounted, the chassis provides the power supply, and each blade has its own CPU, memory and hard disk. Redundant power supplies may be an option. Blade servers generally provide their own management systems and may include a network or storage switch. Contrast with blade PC.
Diskless Blades
With enterprise-class blade servers, disk storage is external, and the blades are diskless. This approach allows for more efficient failover because applications are not tied to specific hardware and a particular instance of the operating system. The blades are anonymous and interchangeable. See blade and processor area network.
personal area network
personal area network
Transmitting data wireless over a short distance. Bluetooth and Wi-Fi Direct are examples of personal area networks (PANs). See Bluetooth and Wi-Fi Direct.
The Most Personal of Networks
In the mid-1990s, IBM's Almaden Research Center developed a method that let people transfer information by touch. It worked by sending a billionth of an amp (nanoamp) through the body, which is actually considerably less current than is generated by people combing their hair.
In 2007, Ident Technology AG was founded to market SKINPLEX in the U.S. Developed in Germany, SKINPLEX uses human skin as the transmission medium. For more information, visit www.skinplex.net. See also processor area network.
Transmitting data wireless over a short distance. Bluetooth and Wi-Fi Direct are examples of personal area networks (PANs). See Bluetooth and Wi-Fi Direct.
The Most Personal of Networks
In the mid-1990s, IBM's Almaden Research Center developed a method that let people transfer information by touch. It worked by sending a billionth of an amp (nanoamp) through the body, which is actually considerably less current than is generated by people combing their hair.
In 2007, Ident Technology AG was founded to market SKINPLEX in the U.S. Developed in Germany, SKINPLEX uses human skin as the transmission medium. For more information, visit www.skinplex.net. See also processor area network.
WAN
WAN
(Wide Area Network) A long-distance communications network that covers a wide geographic area, such as a state or country. The telephone companies and cellular carriers deploy WANs to service large regional areas or the entire nation. Large enterprises have their own private WANs to link remote offices, or they use the Internet for connectivity. Of course, the Internet is the world's largest WAN.
WANs, LANs and MANs
A LAN (local area network) is contained within a building or complex. A MAN (metropolitan area network) generally covers a city or suburb. Following is a bandwidth comparison between major LAN and WAN technologies. See LAN, MAN and personal area network.
(Wide Area Network) A long-distance communications network that covers a wide geographic area, such as a state or country. The telephone companies and cellular carriers deploy WANs to service large regional areas or the entire nation. Large enterprises have their own private WANs to link remote offices, or they use the Internet for connectivity. Of course, the Internet is the world's largest WAN.
WANs, LANs and MANs
A LAN (local area network) is contained within a building or complex. A MAN (metropolitan area network) generally covers a city or suburb. Following is a bandwidth comparison between major LAN and WAN technologies. See LAN, MAN and personal area network.
LAN
LAN
(Local Area Network) A communications network that serves users within a confined geographical area. The "clients" are the user's workstations typically running Windows, although Mac and Linux clients are also used. The "servers" hold programs and data that are shared by the clients. Servers come in a wide range of sizes from Intel-based servers to mainframes. Printers can also be connected to the network and shared (see print server).
Thick and Thin Clients
In a LAN, the client machines are mostly Windows-based PCs that contain their own applications. These "thick" clients are the norm; however, some companies use "thin" clients, which are stripped-down machines. Some are diskless and floppy-only workstations that retrieve all software and data from the server. Windows terminals are also used, which are Windows PCs that act like input/output terminals. They perform no business processing and display only what comes from a central server. See thin client and Windows terminal.
The Network OS
The controlling software in a LAN is the network operating system in the server (Windows, Mac OS, Linux, Unix, NetWare). A component part resides in each client and allows the application to read and write data from the server as if it were on the local machine.
Client workstations can also function as a server, allowing users access to data on another user's machine. These peer-to-peer networks are often simpler to install and manage, but dedicated servers provide better performance and handle higher transaction volume. In large networks, multiple, dedicated servers are used.
The Transport
Data transfer over the network is managed by a transport protocol such as TCP/IP or IPX. The physical transmission is performed by the access method, almost exclusively Ethernet, which is on the motherboard or in the network adapter cards (NICs) plugged into the machines. The actual communications path is the twisted pair or optical fiber cable that interconnects each network adapter. See WAN, TCP/IP, Ethernet and client/server.
Clients and Servers in a LAN
The Software in a Network Client
The Software in a Network Server
(Local Area Network) A communications network that serves users within a confined geographical area. The "clients" are the user's workstations typically running Windows, although Mac and Linux clients are also used. The "servers" hold programs and data that are shared by the clients. Servers come in a wide range of sizes from Intel-based servers to mainframes. Printers can also be connected to the network and shared (see print server).
Thick and Thin Clients
In a LAN, the client machines are mostly Windows-based PCs that contain their own applications. These "thick" clients are the norm; however, some companies use "thin" clients, which are stripped-down machines. Some are diskless and floppy-only workstations that retrieve all software and data from the server. Windows terminals are also used, which are Windows PCs that act like input/output terminals. They perform no business processing and display only what comes from a central server. See thin client and Windows terminal.
The Network OS
The controlling software in a LAN is the network operating system in the server (Windows, Mac OS, Linux, Unix, NetWare). A component part resides in each client and allows the application to read and write data from the server as if it were on the local machine.
Client workstations can also function as a server, allowing users access to data on another user's machine. These peer-to-peer networks are often simpler to install and manage, but dedicated servers provide better performance and handle higher transaction volume. In large networks, multiple, dedicated servers are used.
The Transport
Data transfer over the network is managed by a transport protocol such as TCP/IP or IPX. The physical transmission is performed by the access method, almost exclusively Ethernet, which is on the motherboard or in the network adapter cards (NICs) plugged into the machines. The actual communications path is the twisted pair or optical fiber cable that interconnects each network adapter. See WAN, TCP/IP, Ethernet and client/server.
Clients and Servers in a LAN
This illustration shows one server for each type of service on a LAN. In practice, several functions can be combined in one machine and, for large volumes, multiple machines can be used to balance the traffic for the same service. For example, a large Internet Web site is often made up of several Web servers.
The Software in a Network Client
This shows the various software components that reside in a user's client workstation in a network.
The Software in a Network Server
This shows the network operating system and various system software components in a network server.
IPX
IPX
(Internetwork Packet EXchange) The network layer protocol in the NetWare operating system. Similar to the IP layer in TCP/IP, it contains a network address and allows messages to be routed to a different network or subnet. IPX does not guarantee delivery of a complete message. Just like IP packets, NetWare IPX packets can get dropped from overloaded routers, thus either the application has to ensure delivery of the entire message or NetWare's SPX protocol must be used. See SPX and NetWare.
(Internetwork Packet EXchange) The network layer protocol in the NetWare operating system. Similar to the IP layer in TCP/IP, it contains a network address and allows messages to be routed to a different network or subnet. IPX does not guarantee delivery of a complete message. Just like IP packets, NetWare IPX packets can get dropped from overloaded routers, thus either the application has to ensure delivery of the entire message or NetWare's SPX protocol must be used. See SPX and NetWare.
IPv6
IPv6
(Internet Protocol Version 6) The next generation IP protocol. Started in 1991, the specification was completed in 1997 by the Internet Engineering Task Force (IETF). IPv6 is backward compatible with and is designed to fix the shortcomings of IPv4, such as data security and maximum number of user addresses.
Virtually Unlimited Addresses
IPv6 increases the address space from 32 to 128 bits, providing for a virtually unlimited (for all intents and purposes) number of networks and systems. It also supports quality of service (QoS) parameters for real-time audio and video. Originally called "IP Next Generation" (IPng), IPv6 is expected to slowly replace IPv4, with the two existing side by side for many years.
IPv6 was officially deployed in July 2004 when ICANN added IPv6 records to its DNS root server for the .jp (Japan) and .kr (Korea) country codes.
What Happened to IPv5?
IPv5 was an experimental streaming audio/video protocol, which had nothing to do with the fundamental structure of IP addressing.
(Internet Protocol Version 6) The next generation IP protocol. Started in 1991, the specification was completed in 1997 by the Internet Engineering Task Force (IETF). IPv6 is backward compatible with and is designed to fix the shortcomings of IPv4, such as data security and maximum number of user addresses.
Virtually Unlimited Addresses
IPv6 increases the address space from 32 to 128 bits, providing for a virtually unlimited (for all intents and purposes) number of networks and systems. It also supports quality of service (QoS) parameters for real-time audio and video. Originally called "IP Next Generation" (IPng), IPv6 is expected to slowly replace IPv4, with the two existing side by side for many years.
IPv6 was officially deployed in July 2004 when ICANN added IPv6 records to its DNS root server for the .jp (Japan) and .kr (Korea) country codes.
What Happened to IPv5?
IPv5 was an experimental streaming audio/video protocol, which had nothing to do with the fundamental structure of IP addressing.
HUB vs SWITCH
hub vs. switch
Shared versus dedicated channels. In an Ethernet network, every client, server and network device is wired to a hub or switch. A hub shares the total bandwidth among all users, while a switch provides a dedicated line at full bandwidth between every two devices transmitting to each other. In the 1990s, switches were much more costly than hubs, and devices were carefully evaluated based on the traffic requirement. By the turn of the century, switches became much less expensive, and the popularity of hubs began to wane.
In a small home or office, a hub is generally sufficient. However, if many users are always sending large files to each other, the switch eliminates congestion. See Ethernet.
Shared versus dedicated channels. In an Ethernet network, every client, server and network device is wired to a hub or switch. A hub shares the total bandwidth among all users, while a switch provides a dedicated line at full bandwidth between every two devices transmitting to each other. In the 1990s, switches were much more costly than hubs, and devices were carefully evaluated based on the traffic requirement. By the turn of the century, switches became much less expensive, and the popularity of hubs began to wane.
In a small home or office, a hub is generally sufficient. However, if many users are always sending large files to each other, the switch eliminates congestion. See Ethernet.
file sharing protocol
file sharing protocol
A high-level network protocol that provides the structure and language for file requests between clients and servers. It provides the commands for opening, reading, writing and closing files across the network and may also provide access to the directory services. Sometimes called a "client/server protocol," it functions at the application layer (layer 7 of the OSI model).
In order for a client to have access to multiple servers running different operating systems, either the client supports the file sharing protocol of each operating system or the server supports the file sharing protocol of each client. Software that adds this capability is very common and allows interoperability between Windows, Macintosh, NetWare and Unix platforms. See Samba. See also peer-to-peer network.
A high-level network protocol that provides the structure and language for file requests between clients and servers. It provides the commands for opening, reading, writing and closing files across the network and may also provide access to the directory services. Sometimes called a "client/server protocol," it functions at the application layer (layer 7 of the OSI model).
In order for a client to have access to multiple servers running different operating systems, either the client supports the file sharing protocol of each operating system or the server supports the file sharing protocol of each client. Software that adds this capability is very common and allows interoperability between Windows, Macintosh, NetWare and Unix platforms. See Samba. See also peer-to-peer network.
Operating Transport File Sharing
System Protocol Protocol
DOS NetBIOS SMB
Windows NetBEUI CIFS, SMB
NetWare IPX NCP
Macintosh AppleTalk AFP
Unix TCP/IP NFS, Samba
RAID
RAID
(Redundant Array of Independent Disks) A disk subsystem that increases performance or provides fault tolerance or both. RAID uses two or more hard drives and a RAID controller, which is plugged into motherboards that do not have built-in RAID circuits. Today, most motherboards have RAID built in. In the past, RAID was also accomplished by software only, but was much slower. In the late 1980s, the "I" in RAID stood for "inexpensive," but was later changed to "independent."
In large storage area networks (SANs), floor-standing RAID units are common with terabytes of storage and huge amounts of cache memory. RAID is also used in desktop computers by gamers for speed and by business users for reliability. Following are the various RAID configurations. See NAS and SAN.
RAID 0 - Disk Striping for Performance (Popular)
Widely used for gaming, disk striping interleaves data across multiple drives for performance. However, there are no safeguards against failure.
RAID 1 - Mirroring for Fault Tolerance (Popular)
Widely used, mirroring writes two drives at the same time so that data are duplicated. It provides the highest reliability, but doubles the number of drives needed.
RAID 10 (RAID 1+0)
RAID 10 combines RAID 1 and RAID 0. Drives are mirrored for fault tolerance (RAID 1) and striped for performance (RAID 0). For more speed, RAID 100 combines RAID 10 and 0. It adds a layer of striping (RAID 0) on top of two or more RAID 10 configurations.
RAID 3 - Speed and Fault Tolerance
Data are striped across three or more drives. Used to achieve the highest data transfer because all drives operate in parallel. Using byte level striping, parity bits are stored on separate, dedicated drives. Similar to RAID 3, RAID 4 uses block level striping, but is not as popular. For more on parity computations, see RAID parity.
RAID 5 - Speed and Fault Tolerance (Popular)
Data are striped across three or more drives for performance, and parity bits are used for fault tolerance. The parity bits from two drives are stored on a third drive and are interspersed with user data. RAID 5 is widely used in servers.
RAID 6 - Speed and Fault Tolerance
Similar to RAID 5 but performs two parity computations or the same computation on overlapping subsets of the data. Highest reliability because it can recover from two failed disks, but not widely used.
Big RAID
Little RAID
(Redundant Array of Independent Disks) A disk subsystem that increases performance or provides fault tolerance or both. RAID uses two or more hard drives and a RAID controller, which is plugged into motherboards that do not have built-in RAID circuits. Today, most motherboards have RAID built in. In the past, RAID was also accomplished by software only, but was much slower. In the late 1980s, the "I" in RAID stood for "inexpensive," but was later changed to "independent."
In large storage area networks (SANs), floor-standing RAID units are common with terabytes of storage and huge amounts of cache memory. RAID is also used in desktop computers by gamers for speed and by business users for reliability. Following are the various RAID configurations. See NAS and SAN.
RAID 0 - Disk Striping for Performance (Popular)
Widely used for gaming, disk striping interleaves data across multiple drives for performance. However, there are no safeguards against failure.
RAID 1 - Mirroring for Fault Tolerance (Popular)
Widely used, mirroring writes two drives at the same time so that data are duplicated. It provides the highest reliability, but doubles the number of drives needed.
RAID 10 (RAID 1+0)
RAID 10 combines RAID 1 and RAID 0. Drives are mirrored for fault tolerance (RAID 1) and striped for performance (RAID 0). For more speed, RAID 100 combines RAID 10 and 0. It adds a layer of striping (RAID 0) on top of two or more RAID 10 configurations.
RAID 3 - Speed and Fault Tolerance
Data are striped across three or more drives. Used to achieve the highest data transfer because all drives operate in parallel. Using byte level striping, parity bits are stored on separate, dedicated drives. Similar to RAID 3, RAID 4 uses block level striping, but is not as popular. For more on parity computations, see RAID parity.
RAID 5 - Speed and Fault Tolerance (Popular)
Data are striped across three or more drives for performance, and parity bits are used for fault tolerance. The parity bits from two drives are stored on a third drive and are interspersed with user data. RAID 5 is widely used in servers.
RAID 6 - Speed and Fault Tolerance
Similar to RAID 5 but performs two parity computations or the same computation on overlapping subsets of the data. Highest reliability because it can recover from two failed disks, but not widely used.
Big RAID
EMC has been a leader in high-end RAID systems for years with systems storing multiple terabytes of data. (Image courtesy of EMC Corporation.)
Little RAID
Arco was the first to provide RAID 1 mirroring on inexpensive IDE drives rather than SCSI. This unit took up two drive bays and connected to one Parallel ATA (PATA) cable like a single drive. (Image courtesy of Arco Computer Products, Inc., www.arcoide.com)
DISK MIRRORING
disk mirroring
The recording of redundant data for fault tolerant operation. Data are written on two partitions of the same disk or on two separate disks within the same system. Disk mirroring uses the same controller. RAID 1 provides mirroring, which was first accomplished only with SCSI drives, but later with ATA (IDE) drives. See disk duplexing and RAID.
The recording of redundant data for fault tolerant operation. Data are written on two partitions of the same disk or on two separate disks within the same system. Disk mirroring uses the same controller. RAID 1 provides mirroring, which was first accomplished only with SCSI drives, but later with ATA (IDE) drives. See disk duplexing and RAID.
CLOUD COMPUTING
1) See grid computing.
(2) Using the Web server facilities of a third party provider on the Internet (the "cloud") to store, deploy and run applications. Cloud computing takes two forms. It may refer to "utility" computing in which only the hardware and software infrastructure (operating system, databases, etc.) are offered, or it may refer to "software as a service" (SaaS), which includes the business applications as well. Regardless whether the cloud is infrastructure only or includes applications, major features are self service, scalability and speed.
#1 - Do It Yourself
Users do everything online. They sign on to the service and run their applications as desired. Although a person may initially be involved in setting up the service contract, users make all subsequent changes from their computers, typically from their Web browsers.
#2 - Scalability and Speed
The cloud provides virtually unlimited computing capacity and supports extra workloads on demand. In addition, cloud providers may be connected to multiple Tier 1 Internet backbones for fastest response times and availability.
Infrastructure and Applications
More often than not, cloud computing refers to application service providers (ASPs), who offer the whole ball of wax: the infrastructure as outlined below and the applications as well, relieving the organization of virtually all maintenance. There are two kinds: entirely free to the user such as Google Apps, and paid applications such as Salesforce.com.
This "software-as-a-service" model (SaaS) is a paradigm shift because applications and company data are stored externally. Even if data are duplicated inhouse, copies "in the cloud" create security and privacy issues.
In all its forms, cloud computing is considered the next great wave in IT and is currently the major buzzword.
Infrastructure Only
Using the cloud for computing power only can be more economical than building new datacenters or expanding existing ones to support new projects or seasonal increases. When constructing a datacenter, there are enormous security, environmental and management issues, not to mention hardware/software maintenance forever after. In addition, cloud facilities may be able to withstand natural disasters that meet and exceed military standards, whereas company datacenters are not generally built to these specifications.
Infrastructure-only cloud computing is also called "cloud hosting," "utility computing," "grid hosting" and "grid computing."
For small Web developers and publishers, cloud providers such as Amazon and Google are invaluable (see EC2 and Google App Engine). Because cloud hardware "dynamically scales" (expands capacity on demand), a sudden increase in requests cannot overload a Web server, such as immediately after launching a new product. Configuring sufficient servers inhouse to withstand bursts of traffic means computers run at lower capacity much of the time. Because cloud datacenters charge for actual usage, there is no wasted expense.
In addition, cloud datacenters employ automatic backup and recovery systems as well as utilize the latest virtualization techniques (see server virtualization). However, the way the cloud provides automatic processes differs. In some cases, they are entirely automatic. In others, the developer has to learn how to configure the cloud's software tools to make them automatic.
Private and Hybrid Clouds
Enterprises also create private clouds within their own datacenters. Employing the same server virtualization techniques as the Internet clouds, the private cloud enjoys the same flexibility and self-service capabilities as the public cloud, but with greater control and privacy.
A hybrid cloud is using both private and public clouds. When new applications arise, or if the enterprise cloud is overloaded, the public cloud is used. Migrating virtualized applications from internal servers to the Internet and managing both venues from a central console are issues facing network administrators in 2010 and the decade beyond. See SaaS, rich client, EC2, Google App Engine, Windows Azure, thin client, cloud, colocation, Open Cloud Manifesto and Web application.
(2) Using the Web server facilities of a third party provider on the Internet (the "cloud") to store, deploy and run applications. Cloud computing takes two forms. It may refer to "utility" computing in which only the hardware and software infrastructure (operating system, databases, etc.) are offered, or it may refer to "software as a service" (SaaS), which includes the business applications as well. Regardless whether the cloud is infrastructure only or includes applications, major features are self service, scalability and speed.
#1 - Do It Yourself
Users do everything online. They sign on to the service and run their applications as desired. Although a person may initially be involved in setting up the service contract, users make all subsequent changes from their computers, typically from their Web browsers.
#2 - Scalability and Speed
The cloud provides virtually unlimited computing capacity and supports extra workloads on demand. In addition, cloud providers may be connected to multiple Tier 1 Internet backbones for fastest response times and availability.
Infrastructure and Applications
More often than not, cloud computing refers to application service providers (ASPs), who offer the whole ball of wax: the infrastructure as outlined below and the applications as well, relieving the organization of virtually all maintenance. There are two kinds: entirely free to the user such as Google Apps, and paid applications such as Salesforce.com.
This "software-as-a-service" model (SaaS) is a paradigm shift because applications and company data are stored externally. Even if data are duplicated inhouse, copies "in the cloud" create security and privacy issues.
In all its forms, cloud computing is considered the next great wave in IT and is currently the major buzzword.
Infrastructure Only
Using the cloud for computing power only can be more economical than building new datacenters or expanding existing ones to support new projects or seasonal increases. When constructing a datacenter, there are enormous security, environmental and management issues, not to mention hardware/software maintenance forever after. In addition, cloud facilities may be able to withstand natural disasters that meet and exceed military standards, whereas company datacenters are not generally built to these specifications.
Infrastructure-only cloud computing is also called "cloud hosting," "utility computing," "grid hosting" and "grid computing."
For small Web developers and publishers, cloud providers such as Amazon and Google are invaluable (see EC2 and Google App Engine). Because cloud hardware "dynamically scales" (expands capacity on demand), a sudden increase in requests cannot overload a Web server, such as immediately after launching a new product. Configuring sufficient servers inhouse to withstand bursts of traffic means computers run at lower capacity much of the time. Because cloud datacenters charge for actual usage, there is no wasted expense.
In addition, cloud datacenters employ automatic backup and recovery systems as well as utilize the latest virtualization techniques (see server virtualization). However, the way the cloud provides automatic processes differs. In some cases, they are entirely automatic. In others, the developer has to learn how to configure the cloud's software tools to make them automatic.
Private and Hybrid Clouds
Enterprises also create private clouds within their own datacenters. Employing the same server virtualization techniques as the Internet clouds, the private cloud enjoys the same flexibility and self-service capabilities as the public cloud, but with greater control and privacy.
A hybrid cloud is using both private and public clouds. When new applications arise, or if the enterprise cloud is overloaded, the public cloud is used. Migrating virtualized applications from internal servers to the Internet and managing both venues from a central console are issues facing network administrators in 2010 and the decade beyond. See SaaS, rich client, EC2, Google App Engine, Windows Azure, thin client, cloud, colocation, Open Cloud Manifesto and Web application.
CERTIFICATE
The digital equivalent of an ID card used in conjunction with a public key encryption system. Also called a "digital ID," "digital identity certificate," "identity certificate" and "public key certificate," digital certificates are issued by a trusted third party known as a "certification authority" (CA) such as VeriSign (www.verisign.com) and Thawte (www.thawte.com).
The CA verifies that a public key belongs to a specific company or individual (the "subject"), and the validation process it goes through to determine if the subject is who it claims to be depends on the level of certification and the CA itself.
Creating the Certificate
After the validation process is completed, the CA creates an X.509 certificate that contains CA and subject information, including the subject's public key (details below). The CA signs the certificate by creating a digest (a hash) of all the fields in the certificate and encrypting the hash value with its private key. The encrypted digest is called a "digital signature," and when placed into the X.509 certificate, the certificate is said to be "signed."
The CA keeps its private key very secure, because if ever discovered, false certificates could be created. See HSM.
Verifying the Certificate
The process of verifying the "signed certificate" is done by the recipient's software, which is typically the Web browser. The browser maintains an internal list of popular CAs and their public keys and uses the appropriate public key to decrypt the signature back into the digest. It then recomputes its own digest from the plain text in the certificate and compares the two. If both digests match, the integrity of the certificate is verified (it was not tampered with), and the public key in the certificate is assumed to be the valid public key of the subject.
Then What...
At this point, the subject's identity and the certificate's integrity (no tampering) have been verified. The certificate is typically combined with a signed message or signed executable file, and the public key is used to verify the signatures (see digital signature and code signing). The subject's public key may also be used to provide a secure key exchange in order to have an encrypted two-way communications session (see SSL). See PKI.
The CA verifies that a public key belongs to a specific company or individual (the "subject"), and the validation process it goes through to determine if the subject is who it claims to be depends on the level of certification and the CA itself.
Creating the Certificate
After the validation process is completed, the CA creates an X.509 certificate that contains CA and subject information, including the subject's public key (details below). The CA signs the certificate by creating a digest (a hash) of all the fields in the certificate and encrypting the hash value with its private key. The encrypted digest is called a "digital signature," and when placed into the X.509 certificate, the certificate is said to be "signed."
The CA keeps its private key very secure, because if ever discovered, false certificates could be created. See HSM.
Verifying the Certificate
The process of verifying the "signed certificate" is done by the recipient's software, which is typically the Web browser. The browser maintains an internal list of popular CAs and their public keys and uses the appropriate public key to decrypt the signature back into the digest. It then recomputes its own digest from the plain text in the certificate and compares the two. If both digests match, the integrity of the certificate is verified (it was not tampered with), and the public key in the certificate is assumed to be the valid public key of the subject.
Then What...
At this point, the subject's identity and the certificate's integrity (no tampering) have been verified. The certificate is typically combined with a signed message or signed executable file, and the public key is used to verify the signatures (see digital signature and code signing). The subject's public key may also be used to provide a secure key exchange in order to have an encrypted two-way communications session (see SSL). See PKI.
Major Data Elements in an X.509 Certificate
Version number of certificate format
Serial number (unique number from CA)
Certificate signature algorithm
Issuer (name of CA)
Valid-from/valid-to dates
Subject (name of company or person certified)
Subject's public key and algorithm
Digital signature created with CA's private key
Monday, December 21, 2009
SMTP
Simple Mail Transfer Protocol) The standard e-mail protocol on the Internet and part of the TCP/IP protocol suite, as defined by IETF RFC 2821. SMTP defines the message format and the message transfer agent (MTA), which stores and forwards the mail. SMTP was originally designed for only plain text (ASCII text), but MIME and other encoding methods enable executable programs and multimedia files to be attached to and transported with the e-mail message.
SMTP servers route SMTP messages throughout the Internet to a mail server that provides a message store for incoming mail. The mail server uses the POP3 or IMAP4 access protocol to communicate with the user's e-mail program. See POP3, IMAP4, MIME and messaging system. See also SNMP.
SMTP servers route SMTP messages throughout the Internet to a mail server that provides a message store for incoming mail. The mail server uses the POP3 or IMAP4 access protocol to communicate with the user's e-mail program. See POP3, IMAP4, MIME and messaging system. See also SNMP.
VPN
Virtual Private Network) A private network that is configured within a public network (a carrier's network or the Internet) in order to take advantage of the economies of scale and management facilities of large networks. VPNs are widely used by enterprises to create wide area networks (WANs) that span large geographic areas, to provide site-to-site connections to branch offices and to allow mobile users to dial up their company LANs.
For years, common carriers have built VPNs that appear as a private national or international network to each customer, but, in fact, are sharing the same physical backbone trunks with many customers. VPNs have been built over X.25, Switched 56, frame relay and ATM technologies as well as IP networks. For added security, encryption is often used. See PVC and SVC.
Encrypting data that travels between a remote user and the corporate LAN over the Internet is very popular. It is much more economical than using private, leased lines or making long distance data calls via modem. Today, in fact, many people think that "VPN" and "encrypted connections over the Internet" are synonymous. See computer security and information security.
Internet VPNs
Several protocols are used to provide security over the Internet. For brief transactions at a Web site, SSL is widely used. For extended, secure transmissions, IPsec, L2TP and PPTP are used to provide secure "tunnels" over the Internet. See IPsec, L2TP, PPTP and SSL.
Frame Relay VPNs from Carriers
Carriers offer point-to-point and multipoint VPNs using frame relay. Customer equipment converts packets to frame relay packets. Frame relay VPNs support any network protocol (IP, IPX, SNA, etc.), but adding a location in a multipoint VPN means provisioning virtual circuits from that site to all other sites, which can be costly. See frame relay.
Virtual IP VPNs from Carriers
Carriers offer multipoint networks that accept only IP packets from the customer and run over an IP core. These virtual private routed networks (VPRNs) connect the customer's IP router to the provider's IP router and require some coordination. See MPLS.
Ethernet VPNs from Carriers
Carriers offer services that encapsulate Ethernet frames and deliver them across their network to an Ethernet connection on the other end. A "LAN interconnect" service connects one Ethernet to another. A "transparent LAN" service (TLS) offers multipoint connectivity, typically using frame relay, but has been problematic due to the differences in Ethernet and frame relay architecture. A virtual private LAN service (VPLS) is the latest implementation of a transparent LAN for Ethernet, using an IP and MPLS core to route traffic (see VPLS).
For years, common carriers have built VPNs that appear as a private national or international network to each customer, but, in fact, are sharing the same physical backbone trunks with many customers. VPNs have been built over X.25, Switched 56, frame relay and ATM technologies as well as IP networks. For added security, encryption is often used. See PVC and SVC.
Encrypting data that travels between a remote user and the corporate LAN over the Internet is very popular. It is much more economical than using private, leased lines or making long distance data calls via modem. Today, in fact, many people think that "VPN" and "encrypted connections over the Internet" are synonymous. See computer security and information security.
Internet VPNs
Several protocols are used to provide security over the Internet. For brief transactions at a Web site, SSL is widely used. For extended, secure transmissions, IPsec, L2TP and PPTP are used to provide secure "tunnels" over the Internet. See IPsec, L2TP, PPTP and SSL.
Frame Relay VPNs from Carriers
Carriers offer point-to-point and multipoint VPNs using frame relay. Customer equipment converts packets to frame relay packets. Frame relay VPNs support any network protocol (IP, IPX, SNA, etc.), but adding a location in a multipoint VPN means provisioning virtual circuits from that site to all other sites, which can be costly. See frame relay.
Virtual IP VPNs from Carriers
Carriers offer multipoint networks that accept only IP packets from the customer and run over an IP core. These virtual private routed networks (VPRNs) connect the customer's IP router to the provider's IP router and require some coordination. See MPLS.
Ethernet VPNs from Carriers
Carriers offer services that encapsulate Ethernet frames and deliver them across their network to an Ethernet connection on the other end. A "LAN interconnect" service connects one Ethernet to another. A "transparent LAN" service (TLS) offers multipoint connectivity, typically using frame relay, but has been problematic due to the differences in Ethernet and frame relay architecture. A virtual private LAN service (VPLS) is the latest implementation of a transparent LAN for Ethernet, using an IP and MPLS core to route traffic (see VPLS).
POP
Post Office Protocol 3) A standard interface between a user's e-mail program and the mail server, defined by IETF RFC 1939. POP3 and IMAP4 are the two common mailbox access protocols for e-mail clients such as Outlook, Mail, Eudora and Thunderbird. POP3 is a simple system with limited selectivity. Incoming messages and attachments are downloaded when users check their mail. POP is typically configured to delete the messages on the server after downloading. If the user opts to not delete them, the messages will download again the next time mail is checked. See IMAP4, Internet e-mail service, SMTP and messaging system.
sewag 2 lead
india won the match on yesterday without DHONI . He is known as indian most lucky captain but we won yesterday with sewag . In srilankan innings they start as amazing by both dilshan & tharanga but their middle orders did n't use well as usual .. indian spinner jadeja use condition of the wicket as well. In indian innings sewag open as his usual passion but sachin lead the indian batting in still end but master blaster miss his another ton by karthik's six
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