Introduction to Networks

Network Types

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Different types of Networks

Understand the purpose of a computer network

Create network drawings

Understand Packet Switching

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Enables file sharing (should cut down on printing costs)

Share resources, such as printers, scanners, etc., to get more use out of office equipment (cutting down costs)

Share software with multi-user licenses.

Perform data backups quicker and easier with files on shared drives.

Easier and more manageable Internet connection

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LAN (Local area network) The definition of a LAN has become increasingly vague

over the last ten years.

It was understood that it was interconnected computers at one location i.e. college or a workplace.

Know due to faster technology LAN devices can be used over longer distances.

A LAN can be as small as two computers by using a simple Ethernet connection or can divided into sub networks using switches and routers.

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Using Visio try to recreate the LAN shown below. (Feel free to make it your own)

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WAN (Wide area network)

A WAN is a complex network system, comprising of interconnected LANs.

WANs are used to connect LANs and other types of networks together, so that users and computers in one location can communicate with users and computers in other locations.

WANs are often built using leased lines.A router connects to the LAN on one side and a hub within the WAN on the other

Network protocols including TCP/IP deliver transport and addressing functions.

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http://en.wikipedia.org/wiki/Wide_area_network

Several options are available for WAN connectivity:

Research the following protocols.

PPP – Point-to-Point Protocol (PPP)

ISDN - Integrated Services Digital Network (ISDN)

HDLC - High-level Data Link Control (HDLC)

SDLC - Synchronous Data Link Control (SDLC)

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MAN (Metropolitan area networks) Large computer network that spans a metropolitan area or

campus. The network size falls intermediate between LANs and WANs.

MANs provide Internet connectivity for LANs in a metropolitan region, and connect them to wider area networks like the Internet.

They typically use wireless infrastructure or optical fiber (or fibre) connections to link their sites.

A MAN (like a WAN) is not generally owned by a single organisation. The MAN, its communications links and equipment are generally owned by either a consortium of users or by a network service provider who sells the service to the users.

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Mesh network

A netlike communications network in which there are at least two pathways to each node.

A fully meshed network means that every node has a direct connection to every other node. Most mesh networks are partially meshed and require traversing nodes to go from each node to every other.

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Using the internet look into what a packet is.

Create a network diagram in Visio to represent “SuperJanet”.

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WLAN - Wireless Local Area Network

SAN - Storage Area Network,

Also: 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

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Write brief definition for TEN different types of network…

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Circuit switching establishes fixed bandwidth circuits/channels between nodes and terminals before the users may communicate.

Packet switching is a communication method in which packets are routed between nodes over data links shared with other traffic.

Circuit switching or "connection-oriented data transmission":

Packet switching or "connectionless data transmission":

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A packet is a segment of data sent from one computer or device to another over a network

Computer communications links that do not support packets, such as traditional point-to-point telecommunications links, simply transmit data as a series of bytes, characters, or bitsalone.

When data is formatted into packets, the bitrate of the communication medium can better be shared among users than if the network would have been circuit switched.

By using packet switched networking it is also harder to guarantee a lowest possible bitrate.

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A packet contains the source, destination, size, type, data, and other useful information that helps packet get to its destination and read.

Here is a breakdown of a TCP packet.

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Another name for a packet is a datagram.

Data transferred over the Internet is sent as one or more packets. The most common packet sent is the TCP packet.

The size of a packet is limited, so most data sent over a network is broken up into multiple packets before being sent out and then put back together when received.

When a packet is transmitted over a network, network routers and switches examine the packet and its source to help direct is direction.

During its transmission, network packets can be dropped. If a packet is not received or an error occurs, it is sent again.

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1. What advantage does a circuit-switched network have over a packet-switched network?

2. What advantage does a packet-switched network have over a circuit-switched network ?

Research and evaluate benefits each with description and examples.

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Considered the purpose of a computer network.

Revised some of the different types of networks.

Used Visio to create network diagrams.

Gained an understanding of a Packet Switching.

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