Networking Facts - Computer Bitts

gayheadavonNetworking and Communications

Oct 27, 2013 (3 years and 10 months ago)

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Networking Facts

A
network
is a group of computers (often called
nodes
or
hosts
) that can share information through their
interconnections. A network is made up of the following components:



Computer systems (nodes or hosts)



Transmission media
--
a path for
electrical signals between devices



Network interfaces
--
devices that send and receive electrical signals



Protocols
--
rules or standards that describe how hosts communicate and exchange data

Despite the costs of implementation and maintenance, networks act
ually save organizations money by
allowing them to:



Consolidate (centralize) data storage



Share peripheral devices like printers



Increase internal and external communications



Increase productivity and collaboration

One way to classify networks is based

on the role network devices play:

Network
Type

Description

Peer
-
to
-
Peer

In
peer
-
to
-
peer
networking (also called
workgroups
), each computer controls access to its own
resources. Security controls on each computer identify who can have access to the
comput
er's resources. Advantages of peer to peer networks include:



Easy implementation



Inepensive

Disadvantages of peer to peer networks include:



Difficult to epand (not scalable)



Difficult to support



Lack centralized control



No centralized storage


ient/Server

In
client/server
networking, shared resources reside on special computers called
servers
.
Other computers, called
clients

connect to the server to access resources. Security controls
on the server identify which clients can have resource access
. Advantages of client/server
networks include:



Easily epanded (scalable)



Easy support



Centralized services



Easy to backup

Disadvantages of client/server networks include:



Server operating systems are epensive



Requires etensive advanced planning

Another way to classify networks is based on size.



A Local Area Network (LAN) is a network in a small geographic area, like in an office. A series of
connected LANs, or a LAN connected across several buildings or offices, is called an
internetwork
.



A Wi
de Area Network (WAN) is a group of LANs that are geographically isolated but connected to
form a large internetwork.

In order for devices on a network to communicate, they must be using the same protocols. A
protocol
is a
rule that identifies some aspect

of how computers communicate on a network. For two computers to
communicate, they must be using the same protocols. Protocols are grouped into protocol
suites
, or sets of
related protocols that are meant to be used together. Common protocol suites include
:

Protocol

Description

TCP/IP

TCP/IP is the protocol suite used on the Internet and on most networks. Nearly all computers
today use TCP/IP for communication.

IPX/SPX

IPX/SPX is the protocol suite used on legacy NetWare networks (networks with a NetWare

version prior to version 5). One way to configure a Microsoft client computer to connect to a
NetWare server running IPX/SPX is to install the NWLink protocol software supplied by Microsoft.

AppleTalk

AppleTalk is the protocol suite used by early Apple M
acintosh computers.

NetBIOS

NetBIOS is the term used to describe the combination of two protocols: NetBEUI and NetBIOS.
NetBIOS was used in early Windows networks. Because NetBIOS is a non
-
routable protocol, it
was often combined with TCP/IP or IPX/SPX to

enable internetwork communications.

Beginning with Windows 2000, NetBIOS is no longer required. However, NetBIOS might be
needed if the network includes clients running previous versions of Windows.

Note:

IPX/SPX, AppleTalk, and NetBIOS are rarely used
on current systems. Nearly all systems today use
TCP/IP.

Communication between hosts on a network generally takes one of three forms:



Simplex
--
one
-
way communication from a sender to a receiver.



Half
-
duplex
--
two
-
way communication between two hosts. Communi
cation only travels in one
direction at a time.



Full duplex
--
two
-
way communication between hosts. Communication can travel in both directions
simultaneously.

The network
bandwidth

is a rating of how much data can be sent over a network.