groups are the Institute of Electrical and
Electronic Engineers (IEEE), American National Standards
Institute (ANSI), Telecommunications Industry Association
(TIA), Electronic Industries Alliance (EIA) and the
International Telecommunications Union (ITU), formerly known as
the Comité Consultatif International Téléphonique et
Télégraphique (CCITT). Web Links TCP/IP Suite
http://www.protocols.com/pbook/tcpip.htm
Content
2.1 Networking Terminology 2.1.6
Local-area networks (LANs) LANs consist of the
following components: - Computers
- Network
interface cards
- Peripheral devices
- Networking media
- Network devices
LANs
make it possible for businesses that use computer technology to
locally share files and printers efficiently, and make internal
communications possible. A good example of this technology is
e-mail. They tie data, local communications, and computing
equipment together. Some common LAN technologies are:
Web Links LAN Basics http://www.commweb.com/article/
COM20020517S0006
Content 2.1 Networking
Terminology 2.1.7 Wide-area networks
(WANs) WANs interconnect LANs, which then provide access to
computers or file servers in other locations. Because WANs
connect user networks over a large geographical area, they make
it possible for businesses to communicate across great
distances. Using WANs allows computers, printers, and other
devices on a LAN to share and be shared with distant locations.
WANs provide instant communications across large geographic
areas. The ability to send an instant message (IM) to someone
anywhere in the world provides the same communication
capabilities that used to be only possible if people were in
the same physical office. Collaboration software provides
access to real-time information and resources that allows
meetings to be held remotely, instead of in person. Wide-area
networking has also created a new class of workers called
telecommuters, people who never have to leave their homes to go
to work. WANs are designed to do the following:
- Operate over a large geographically separated areas
- Allow users to have real-time communication capabilities
with other users
- Provide full-time remote resources
connected to local services
- Provide e-mail, World
Wide Web, file transfer, and e-commerce services
Some common WAN technologies are: - Modems
- Integrated Services Digital Network (ISDN)
- Digital Subscriber Line (DSL)
- Frame Relay
- US (T) and Europe (E) Carrier Series – T1, E1, T3, E3
- Synchronous Optical Network (SONET)
Web Links WAN Basics http://www.webwisdom.com/edu_content/
cps640fall00/lectures/ module3/WAN/ sld004.htm
Content
2.1 Networking Terminology 2.1.8
Metropolitan-area networks (MANs) A MAN is a network
that spans a metropolitan area such as a city or suburban area.
A MAN usually consists of two or more LANs in a common
geographic area. For example, a bank with multiple branches may
utilize a MAN. Typically, a service provider is used to connect
two or more LAN sites using private communication lines or
optical services. A MAN can also be created using wireless
bridge technology by beaming signals across public areas.
Web Links Lab Exercise: Metropolitan area network
http://searchnetworking.techtarget.com/ sDefinition/0,,sid7_
gci214083,00.html
Content 2.1 Networking
Terminology 2.1.9 Storage-area networks
(SANs) A SAN is a dedicated, high-performance network used
to move data between servers and storage resources. Because it
is a separate, dedicated network, it avoids any traffic
conflict between clients and servers. SAN technology allows
high-speed server-to-storage, storage-to-storage, or
server-to-server connectivity. This method uses a separate
network infrastructure that relieves any problems associated
with existing network connectivity. SANs offer the following
features: - Performance – SANs enable concurrent
access of disk or tape arrays by two or more servers at high
speeds, providing enhanced system performance.
- Availability – SANs have disaster tolerance built
in, because data can be mirrored using a SAN up to 10
kilometers (km) or 6.2 miles away.
- Scalability – Like a LAN/WAN, it can use a variety
of technologies. This allows easy relocation of backup data,
operations, file migration, and data replication between
systems.
Web Links The Lowdown on SAN
http://www.gcn.com/21_16/guide/ 19055-1.html
Content
2.1 Networking Terminology
2.1.10 Virtual private network (VPN) A VPN is a
private network that is constructed within a public network
infrastructure such as the global Internet. Using VPN, a
telecommuter can access the network of the company headquarters
through the Internet by building a secure tunnel between the
telecommuter’s PC and a VPN router in the headquarters. Web
Links VPN's and Other Remote Access
http://www.pcunix.com/Basics/vpn.html
Content
2.1 Networking Terminology
2.1.11 Benefits of VPNs Cisco products support the
latest in VPN technology. A VPN is a service that offers
secure, reliable connectivity over a shared public network
infrastructure such as the Internet. VPNs maintain the same
security and management policies as a private network. They are
the most cost-effective method of establishing a point-to-point
connection between remote users and an enterprise customer's
network. The following are the three main types of VPNs:
- Access VPNs – Access VPNs provide remote access to a
mobile worker and small office/home office (SOHO) to the
headquarters of the Intranet or Extranet over a shared
infrastructure. Access VPNs use analog, dialup, ISDN, digital
subscriber line (DSL), mobile IP, and cable technologies to
securely connect mobile users, telecommuters, and branch
offices.
- Intranet VPNs – Intranet VPNs link
regional and remote offices to the headquarters of the internal
network over a shared infrastructure using dedicated
connections. Intranet VPNs differ from Extranet VPNs in that
they allow access only to the employees of the
enterprise.
- Extranet VPNs – Extranet VPNs link
business partners to the headquarters of the network over a
shared infrastructure using dedicated connections. Extranet
VPNs differ from Intranet VPNs in that they allow access to
users outside the enterprise.
Web Links VPN
Overview http://www.clavister.com/manuals/ver8x/
manual/vpn/vpn_overview.htm
Content 2.1
Networking Terminology 2.1.12 Intranets and
extranets One common configuration of a LAN is an Intranet.
Intranet Web servers differ from public Web servers in that the
public must have the proper permissions and passwords to access
the Intranet of an organization. Intranets are designed to
permit access by users who have access privileges to the
internal LAN of the organization. Within an Intranet, Web
servers are installed in the network. Browser technology is
used as the common front end to access information such as
financial data or graphical, text-based data stored on those
servers. Extranets refer to applications and services that are