How to Choose an Internet Service Provider

You have a growing array of ISPs to choose from, offering
a wide range of services and pricing structures. An ISP can
be a commercial business or a local university, state agency,
or nonprofit organization. You can find out about ISPs in
your area through the Internet, from advertisements or
the yellow pages, and from Internet books and guides.
You also will find a list of Internet service providers on the
World Wide Web at http://thelist.internet.com
Factors to consider when evaluating ISPs include:
Price
Some ISPs offer access at a fixed rate per month or year.
Others offer service at an hourly rate or by charging per
megabyte of data transferred or archived. If you’re not certain
what your usage level will be, it makes sense to begin with
a fixed-rate plan and then monitor usage. Generally, campus
budgets can handle a fixed commitment of a known amount
more easily than a variable commitment.
Support
If your campus does not have its own networking staff or is
not supported by a central office staff, extra support from
the ISP is a necessity. Ask the provider about onsite configuration
services, training, startup software supplied with the
service, and whether the provider operates a help desk with
phone or e-mail consultation. In addition, peer assistance
can prove invaluable, and some service providers organize
user meetings and similar gatherings to help their customers
use the Internet more effectively.
Access
If the ISP offers dialup access, be sure to ask about the size
of the modem pool and the number of customers the ISP is
serving. Ask the following questions:
• Does the ISP enforce maximum session times and provide
password-protected access?
• Does the ISP use a single access number or a pool of numbers?
• What connection speeds are available? (For example, make
sure the ISP can connect high-speed analog modems—
33.6 K and 56 K—or ISDN digital modems—128 K—if
you have this service. Also note that as of this writing, standards
for 56-K modems were still not solidified. Make
sure your 56-K technology is compatible with your ISP’s.)


Performance
It is important to know how the service provider is connected
to the Internet. For example, it is not effective to have a
T1 leased-line connection from your campus to an ISP if the
ISP is connected to the Internet via a T1 connection or less,
especially if the ISP supports several customers. Generally,
higher connection speeds allow a service provider to
accommodate many users and operate more efficiently.
Additional Services
Internet connectivity requires ongoing network administration
configuration and maintenance. Your ISP may offer
these services, so be sure to ask.
For dialup users: ask your ISP if maintenance of a user
account and mailbox is offered on your behalf, with ample
mail spool space for the number of users who can receive
e-mail at your address. The spool space is very important
because it determines how much content your mailbox
will hold before rejecting new messages.
For direct access users: ask if your ISP offers registration
of network identifiers, such as Internet domain names and
IP addresses. You will also need an Internet server computer
that performs the following functions:
• Domain Name System (DNS)—Provides translation
from URL addresses (for example, www.cisco.com) to
numerical addresses (for example, 198.92.30.31)
• Electronic mail service—Establishes e-mail accounts and
allows campus users to receive and send e-mail
• USENET news—Maintains a local usenet news
conferencing system
• World Wide Web or Gopher publishing—Allows you
to publish information and make it accessible to the
Internet community
Commercial Internet server packages that run on a variety
of platforms are available, or your ISP can assist with many
of these services (see right—“How to Create Your Own
Web Site”).

Read More →

How to Connect to the Internet

How to Connect to the Internet

How to Connect to the Internet
The Internet is a global network of thousands of computers,
growing by leaps and bounds each year. It allows a worldwide
community comprising tens of millions of people to
communicate over any distance, access information from
anywhere in the world, and publish text and images instantly.
The Internet is a link to the information resources of
campuses, libraries, and businesses, assisting in research
projects and cross-cultural studies and permitting a free
flow of ideas and studies between students, faculty, and
their peers.
Remarkably, however, a large majority of classrooms
still lack Internet connections. If your campus is among
them, you will be pleased to hear that connecting to the
Internet is easier than ever.

Where connections once required costly special services,
you now have a range of options. Commercial online
services such as America Online and the Microsoft network
offer dialup Internet access for $20 or less per month. ISPs
offer dialup and shared access connections for a variety of
prices, based on a range of line speeds up to T3 (45 Mbps)
for environments with heavy demand or a large number
of users.
On the hardware side, you can make a dialup connection
with a modem attached to one computer or a router
attached to your local-area network, allowing multiple
users to access the Internet.
Modem connections are inexpensive and easy to acquire,
so they are a good idea if you’re just starting out or if your
campus has only a few computers. However, only one person
can use a modem at any given time, leading to heavy
competition for Internet access. A single router can provide
a shared-access solution, accommodating multiple users
and multiple simultaneous Internet connections. It connects
you directly to a router at your ISP’s location.
However you choose to connect, your window on the
Internet is a browser such as Netscape Navigator or
Microsoft Internet Explorer: easy-to-use programs that link
you to any active site on the Internet

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A Wide-Area Network for a Small District

A Wide-Area Network for a Small District
To improve communications between campuses and their central office, the campuses decide to install a wide-area network. The upgrade economizes on Internet connectivity
by offering all campuses a connection through a central high-speed line

.

A Community College WAN
A growing community college system sees rising network traffic at its three campuses. It wants to install future-ready local networks to support multimedia applications and to
provide high-speed WAN links that will allow south and west campus students to take advantage of north campus courses via the network (distance learning). In addition,
because many students commute from great distances, the college wants to allow students at all three campuses to dial up their local servers from home and retrieve assignments
and communicate with professors.

Read More →

Modems vs. Routers

Modems vs. Routers

When choosing between modems and routers for remote
access to a central network or the Internet, consider the
following pros and cons:
Modems
• Inexpensive
• Good for one user or limited remote access for a small group
• Portable, so they can be used remotely from any location with
a phone line
• Compatible with existing telephone lines
• Connections can be made at a relatively low cost (essentially
the same as a local or long-distance phone call)
Routers
• Support faster WAN connections than modems
• Support multiple users
• Many routers have a “live” connection (so you don’t
get busy signals), and you save time not having to dial up
the connection
• The connections are more reliable than with telephone lines
but may be more costly than ordinary phone lines and may not
support voice calls
• Offer data encryption (for enhanced security) in addition to
data compression (for enhanced performance)
Dial-on-demand routing” (DDR) is sometimes used as a
compromise between the dialup method of connecting and fullfledged
routing. “Dial-on-demand” means the router establishes
(and is charged for) a connection only when the connection is in
use. This solution uses a basic router paired with either a modem
or an ISDN line, which makes the calls as needed, when the
router requests a connection.

Read More →

ISDN

ISDN

ISDN is a service that operates at 128 Kbps and is available

from your phone company. Charges for ISDN connections

usually resemble those for analog lines—you pay per call

and/or per minute, usually depending on distance. ISDN

charges also can be flat rate if linked to a local Centrex system.

Technically, ISDN consists of two 64-Kbps channels

that work separately. Load-balancing or “bonding” of the

two channels into a 128-K single channel is possible when

you have compatible hardware on each end of a connection

(for instance, between two of your campuses). What’s more,

as a digital service, ISDN is not subject to the “line noise”

that slows most analog connections, and thus offers actual

throughput much closer to its promised maximum rate.

You can make ISDN connections either with an ISDNready

router or with an ISDN terminal adapter (also

called an ISDN modem) connected to the serial port of your

router. Again, modems are best for single users, because

each device needs its own modem, and only one “conversation”

with the outside world can happen at any one time.

Your ISDN router, modem, or terminal adapter may come

with analog ports, allowing you to connect a regular

telephone, fax, modem, or other analog phone device. For

example, a ISDN router with an analog phone jack would

allow you to make phone calls and send faxes while staying

connected via the other ISDN digital channel.

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Analog Lines

Analog Lines

Using analog lines to dial out to other networks or to
the Internet—or to allow remote users to dial into your
network—is a straightforward solution. Most ordinary
phone lines are analog lines. Connect a modem to your
computer and to a wall jack and you’re in business. You
pay for a connection as you would pay for a phone call—
by the minute, or a set rate per local call (long distance
charges are the same as for a long distance telephone call).
At present, the fastest analog modems operate at
56 Kbps for transferring data. With today’s larger file sizes
and graphically sophisticated World Wide Web sites on the
Internet, you should look for modems that operate at a
minimum of 33.6 Kbps (also called V.34) and have
V.42 (error correction) and V.42bis (data compression)
capabilities for better performance.
While modems offer a simple solution for dialout
connections to other LANs and the Internet, they do not scale
well as your network grows. Each modem can support only
one remote “conversation” at a time, and each device that
wants to connect with the outside world needs a modem.
See the examples in the next section for ways to overcome
this limitation by installing a router for wide-area communications

and your Internet link.


Analog vs. Digital

The difference between analog and digital signals is very important
for data communications. The most familiar “analog”
communication is a phone call. Varying electrical voltage reflects
the variations in the volume and tone of the human voice. By
contrast, digital communications use a series of 1s and 0s to
carry information from point to point. Modems actually convert
the digital data of one computer into an analog signal for transmission
over the phone lines. On the receiving end, another
modem converts the analog signal back into a series of 1s and 0s,
so the receiving computer can interpret the transmission. Today,
phone companies can offer fully digital service between LANs
(leased lines such as 56 K, 384 K, and T1s are digital services), or
Integrated Services Digital Network (ISDN) which allows dialup
connections on an as-needed basis. When it comes to moving
data, digital communications are less susceptible to errors and
faster than analog signals because they are not susceptible to

problems such as electrical “noise” on transmission lines.

Read More →

Remote Access and Wide-Area Networks

                 Remote Access and Wide-Area Networks

LANs accommodate local users—people within a building
or on a campus. WANs connect users and LANs spread
between various sites, whether in the same city, across the
country, or around the world. “Remote access” refers to
a simple connection, usually dialed up over telephone lines
as needed, between an individual user or very small
branch office and a central network.
Your campus gains access to the Internet through
some type of remote connection. A single user can use a
modem to dial up an Internet service provider (ISP). Multiple
users within a campus might choose to rely on a router
to connect to the ISP, who then connects the campus to
the Internet.
In general, LAN speeds are much greater than WAN
and remote access speeds. For example, a single shared-
Ethernet connection runs at 10 Mbps (mega means “million”).
Today’s fastest analog modem runs at 56 kilobits per second
(Kbps) (kilo means “thousand”)—less than one percent of
the speed of an Ethernet link. Even the more expensive,
dedicated WAN services such as T1 lines don’t compare (with
bandwidth of 1.5 Mbps, a T1 lines has only 15 percent of
the capacity of a single Ethernet link). For this reason, proper
network design aims to keep most traffic local—that is,
contained within one site—rather than allowing that traffic

to move across the WAN.

Read More →

Networking Technologies Overview

Networking Technologies Overview

Ethernet has been around since the late 1970s and remains

the leading network technology for local-area networks

(LANs). (A LAN is a network contained in a building or

on a single campus.) Ethernet is based on carrier sense

multiple access with collision detection (CSMA/CD). (See

the margin note on Token Ring for another basic style

of network communication.)

Simply put, an Ethernet workstation can send data

packets only when no other packets are traveling on the

network, that is, when the network is “quiet.” Otherwise,

it waits to transmit, just as a person might wait for another

to speak during conversation.

If multiple stations sense an opening and start sending

at the same time, a “collision” occurs. Then, each station

waits a random amount of time and tries to send its packet

again. After 16 consecutive failed attempts, the original

application that sent the packet has to start again. As more

people try to use the network, the number of collisions,

errors, and subsequent retransmits grows quickly, causing

a snowball effect.

Collisions are normal occurrences, but too many

can start to cause the network to slow down. When more

than 50 percent of the network’s total bandwidth is used,

collision rates begin to cause congestion. Files take longer

to print, applications take longer to open, and users are

forced to wait. At 60 percent or higher bandwidth usage,

the network can slow dramatically or even grind to a halt.

Read More →

Switches

Switches

Switches are smarter
than hubs and offer
more bandwidth. A
switch forwards data
packets only to the
appropriate port for the
intended recipient, based on information in each packet’s
header. To insulate the transmission from the other ports,
the switch establishes a temporary connection between
the source and destination, then terminates the connection
when the conversation is done.
As such, a switch can support multiple “conversations”
and move much more traffic through the network than
a hub. A single eight-port Ethernet hub provides a total of
10 megabits per second (Mbps) of data-carrying capacity
shared among all users on the hub. A “full-duplex,” eight-port
Ethernet switch can support eight 10-Mbps conversations
at once, for a total data-carrying capacity of 160 Mbps.
“Full-duplex” refers to simultaneous two-way communications,
such as telephone communication.With half-duplex communications,
data can move across the cable or transmission
medium in just one direction at a time.
Examples of Cisco switch products:
Cisco 1548 Micro Switch 10/100
Cisco Catalyst® Series
For example...Switches are like a phone system with private
lines in place of the hub’s “party line.” Jane Tipton at the
Berkeley Hotel calls Bill Johnson in another room, and the
operator or phone switch connects the two of them on a
dedicated line. This allows more conversations at a time,
so more guests can communicate.

Read More →

Hubs

Hubs

Hubs, or repeaters, are
simple devices that interconnect
groups of users.
Hubs forward any data
packets they receive over
one port from one workstation—
including e-mail, word processing documents,
spreadsheets, graphics, or print requests—to all of their
remaining ports. All users connected to a single hub or
stack of connected hubs are in the same “segment,” sharing
the hub’s bandwidth or data-carrying capacity. As more
users are added to a segment, they compete for a finite
amount of bandwidth devoted to that segment.
Examples of Cisco hub products:
Cisco Micro Hub series
Cisco FastHub® series
For example...To understand how a hub serves your campus
network, imagine a hotel with just one phone line available
to all guests. Let’s say one guest wants to call another. She
picks up her phone and the phone rings in all rooms. All
the other guests have to answer the phone and determine
whether or not the call is intended for them. Then, as long
as the conversation lasts, no one else can use the line. With
only a few guests, this system is marginally acceptable.
However, at peak times of the day—say, when everyone
returns to their rooms at 6 p.m.—it becomes difficult to
communicate. The phone line is always busy.

Read More →

Basic Networking Components

Basic Networking Components

Clients and Servers

Often, as a network grows and more computers are

added, one computer will act as a server—a central storage

point for files or application programs shared on the network.

Servers also provide connections to shared peripherals

such as printers. Setting up one computer as a server

prevents you from having to outfit every networked computer

with extensive storage capability and duplicate costly

peripherals. The computers that connect to the server are

called clients.

Note that you don’t need to have a dedicated server in
your network. With only a few computers connected,
networking can be “peer to peer.” Users can exchange files
and e-mail, copy files onto each others’ hard drives and
even use printers or modems connected to just one computer.
As more users are added to the network, however, having
a dedicated server provides a central point for management

duties such as file backup and program upgrades.


Wiring and Cable
Networks use three primary types of wiring (also referred
to as “media”):
Twisted-pair—the industry standard in new installations.
This wire comes in several “standards.” Unshielded twisted
pair (UTP) Category 3 wire (also called 10BaseT) is
often used for your phone lines, and UTP Category 5 (also
called 10Base2) wire are the current networking standards.
Coaxial—resembles round cable TV wiring.
Fiber-optic—usually reserved for connections between
“backbone” devices in larger networks, though in some
very demanding environments, highly fault resistant fiberoptic
cable is used to connect desktop workstations to the
network and to link adjacent buildings. Fiber-optic cable
is the most reliable wiring but also the most expensive.
Care should be taken in selecting the cabling for your
classrooms and buildings. You want to be sure the wires
running through ceilings and between walls can handle
not only your present needs, but any upgrades you foresee
in the next several years. For instance, Ethernet can use
UTP Category 3 wiring. However, Fast Ethernet requires at
least the higher-grade UTP Category 5 wiring. As a result, all
new wiring installations should be Category 5. You may
also want to explore plenum cable, which can be routed
through many types of heating and cooling ducts in ceilings.
Check with your architect or wiring contractor to ensure
this process is fire code compliant.
Network interface cards
Network interface cards
(NICs), or adapters, are
usually installed inside
a computer’s case. With
portable and notebook
computers, the NIC is
usually in the credit cardsized
PC card (PCMCIA) format, which is installed in a
slot. Again, when selecting NICs, plan ahead. Ethernet
NICs support only Ethernet connections, while 10/100
NICs cost about the same and can work with either
Ethernet or higher-performance Fast Ethernet connections.
In addition, you need to ensure that your NICs will
support the type of cabling you will use—twisted-pair
(also called 10BaseT), coaxial (also called 10Base2), or
a mixture of both.
Network Interface Card
Twisted Pair Coaxial Fiber

Read More →

The Building Blocks: Basic Components of Networks

The Building Blocks: Basic Components of Networks

There are as many definitions for the term “network” as there are networks. However, most people would agree that networks are collections of two or more connected computers. When their computers are joined in a network, people can share files and peripherals such as modems,

printers, tape backup drives, and CD-ROM drives. When networks at multiple locations are connected using services available from phone companies, people can send e-mail,

share links to the global Internet, or conduct video conferences in real time with other remote users on the network.

Every network includes:
• At least two computers
• A network interface on each computer (the device that
lets the computer talk to the network—usually called
a network interface card [NIC] or adapter)
• A connection medium—usually a wire or cable, but
wireless communication between networked computers
and peripherals is also possible
• Network operating system software—such as Microsoft
Windows 95 or Windows NT, Novell NetWare, AppleShare,
or Artisoft LANtastic
Most networks—even those with just two computers—also
have a hub or a switch to act as a connection point between
the computers.

Read More →

Most people wouldn’t use the terms “networking” and
“basic”in the same sentence. However, while the underlying
principles of networking are somewhat complex, building
a network can be very simple given the right tools and a basic
understanding of how they work together.
With networks, starting small and planning to grow
makes perfect sense. Even a modest network can pay
large dividends by saving time; improving communication
between faculty, students, and parents; increasing productivity;
and opening new paths to learning resources located
anywhere in the world. In this respect, networks are like
cars. You don’t have to know the details about how the engine
works to be able to get where you need to go.
As a result, this guide does not attempt to make you
a networking expert. Instead, it has been carefully designed
to help you:
• Understand the primary building blocks of networks and
the role each one plays.
• Understand the most popular networking technologies
or methods of moving your data from place to place.
• Determine which approach to networking and which
technologies are best for your campus or district campus.
Throughout “Cisco Networking Essentials for Educational
Institutions,” you will find Margin Notes—helpful sidelights
on subjects related to the main concepts in each section.
Terms highlighted in color may be found in the glossary
in back.

Read More →

hat This Guide Can Do for You 

1. The Building Blocks: Basic Components of Networks
2. Clients and Servers 
3. Wiring and Cable 
4. Network Interface Cards 
5. Hubs 
6. Margin Note: Network Management 
7. Margin Note: Modems 
8. Switches 
9. Routers 
10. Margin Note: Uninterruptible Power Supplies 
11. Margin Note: Bridges 
12. Networking Technologies Overview 
13. Local-Area Networks: Ethernet and Fast Ethernet 
14. Remote Access and Wide-Area Networks 
15. Margin Note: Token Ring 
16. Margin Note: High-Speed LAN Technologies 
17. Analog Lines 
18. Margin Note: Analog vs. Digital 
19. ISDN 
20. Margin Note: Modems vs. Routers 
21. Leased Lines 
22. Margin Note: The Universal Service Fund, or E-Rate 
23. Margin Note: Fund-Raising for Networking Projects 
24. Margin Note: Remote Access Servers 
25. Which Service Is Right for You? 

Education Networking Examples 14

2. A Local-Area Network at a Campus 14
3. As the Campus Network Grows 15
4. A Wide-Area Network for a Small District 16
5. A Community College WAN 16
6. Making the Right Connection: Network How-Tos 17
7. How to Connect to the Internet 17
8. How to Choose an Internet Service Provider 19
9. How to Create Your Own Web Site 20
10. Margin Note: Instant Web Content for Education 20
11. Margin Note: Security 20
12. Basic Network Design: Considerations 21
13. A Problem Solvers’ Guide to Relieving Congestion 21
14. How to Spot Network Congestion 21
15. Good Network Design: The 80-20 Rule 23
16. Giving Your Network a Performance Boost 24
17. Dedicated Bandwidth to Workgroups and Servers 25
18. Margin Note: Types of Ethernet Traffic 25
19. Making the Most of Your
20. Existing Equipment as Your Network Evolves 26
21. Networking Basics Checklist 27
22. For Building a Small LAN 27
23. For Connecting Buildings on a Campus 27
24. For Connecting to Another Campus or District 28
25. Margin Note: Training and Support 28

Read More →

Cisco Networking Essentials

Cisco Networking Essentials

Cisco Systems, Inc., the worldwide leader
in networking for the Internet, has
prepared this guide to make networking
easier for your campus or district. If
you’re new to networking, it’s an ideal
introduction, starting with the most basic of components and helping you pinpoint the
best technologies and design for your network. If you already know your networking
ABCs, look to this guide for straightforward explanations of key terms and concepts to
keep building your knowledge base.
Cisco solutions are at the foundation of thousands of education networks worldwide,
from leading universities to campus computer labs. We have a strong commitment
to making education networks powerful, practical learning resources and preparing
today’s students to excel in the information economy. What’s more, 80 percent of the
routers that make up the Internet are from Cisco. Virtually all Internet traffic flows
through Cisco equipment. So when you install Cisco, you’re choosing the networking
equipment proven suitable for the world’s largest and fastest-growing networks.
For details on Cisco solutions for your networks or education initiatives,

call 800 778 3632, ext. 6030, or visit our Web site at www.cisco.com/edu.

Read More →

A Virtual Private Network

A Virtual Private Network (VPN) makes protected connections called VPN tunnels between a local client and a remote server, usually over the Internet. VPNs can be difficult to set up and keep running due to the specialized technology involved. When a VPN connection fails, the client program reports an error message typically including a code number. Hundreds of different VPN error codes exist but only certain ones appear in the majority of cases.

Many VPN errors require standard network troubleshooting procedures to resolve:

Ensure the computer running the VPN client is connected to the Internet (or other wide area network), and that access to the outside network is working
Ensure the VPN client has correct network settings required to work with the target VPN server
Temporarily turn off the local network firewall to determine whether it is interfering with VPN communications. Some types of VPNs require certain ports to be kept open


1. VPN Error 800
"Unable to establish connection" – The VPN client cannot reach the server. This can happen if the VPN server is not properly connected to the network, the network is temporarily down, or if the server or network is overloaded with traffic. The error also occurs if the VPN client has incorrect configuration settings. Finally, the local router may be incompatible with the type of VPN being used and require a router firmware update.
http://www.verifiedvpn.com/index.jhtml?partner=^BA4^xdm101&gclid=CKr12artv8ACFUjHtAodtW0ASg

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WAN - Wide Area Network

WAN - Wide Area Network

As the term implies, a WAN spans a large physical distance. The Internet is the largest WAN, spanning the Earth.

As the term implies, a WAN spans a large physical distance. The Internet is the

 A WAN is a geographically-dispersed collection of LANs. A network device called a router connects LANs to a WAN. In IP networking, the router maintains both a LAN address and a WAN address.

A WAN differs from a LAN in several important ways. Most WANs (like the Internet) are not owned by any one organization but rather exist under collective or distributed ownership and management. WANs tend to use



Other Types of Area Networks

While LAN and WAN are by far the most popular network types mentioned, you may also commonly see references to these others:
Wireless Local Area Network - a LAN based on WiFi wireless network technology
Metropolitan Area Network - a network spanning a physical area larger than a LAN but smaller than a WAN, such as a city. A MAN is typically owned an operated by a single entity such as a government body or large corporation.
Campus Area Network - a network spanning multiple LANs but smaller than a MAN, such as on a university or local business campus.
Storage Area Network - connects servers to data storage devices through a technology like Fibre Channel.
System Area Network - links high-performance computers with high-speed connections in a cluster configuration. Also known as Cluster Area Network.

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One way to categorize the different types of computer network designs is by their scope or scale. For historical reasons, the networking industry refers to nearly every type of design as some kind of area network. Common examples of area network types are:

• LAN - Local Area Network
• WLAN - Wireless Local Area Network
• WAN - Wide Area Network
• MAN - Metropolitan Area Network
• SAN - Storage Area Network, System Area Network, Server Area Network, or sometimes Small Area Network
• CAN - Campus Area Network, Controller Area Network, or sometimes Cluster Area Network
• PAN - Personal Area Network
• DAN - Desk Area Network

LAN and WAN were the original categories of area networks, while the others have gradually emerged over many years of technology evolution.
Note that these network types are a separate concept from network topologies such as bus, ring and star.

AN - Local Area Network

A LAN connects network devices over a relatively short distance. A networked office building, school, or home usually contains a single LAN, though sometimes one building will contain a few small LANs (perhaps one per room), and occasionally a LAN will span a group of nearby buildings. In TCP/IP networking, a LAN is often but not always implemented as a single IP subnet .
In addition to operating in a limited space, LANs are also typically owned, controlled, and managed by a single person or organization. They also tend to use certain connectivity technologies, primarily Ethernet and Token Ring.

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Computer Networks

Computer Networks
Wireless Networks
Communications Network
Network Computing
About Network Security
Network Traffic
Network Management
Telecommunication Network

Bus, ring and star network topology diagrams

A computer network topology is the physical communication scheme used by connected devices. These pages illustrate the common computer network topologies including bus, ring and star topology diagrams. More complex networks can be built as hybrids of two or more of these basic topologies.
Our Expert Recommends

Network Topology Tutorial
Introduction to Area Networks
Network Bandwidth and Latency
The OSI Model
Network Protocols
LAN - Local Area Network
WAN - Wide Area Network

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