M4 - U1 - S1 - Network Components

Network

• Two or more computer systems linked together by some form of transmission medium

  • Enables them to share information

• Provides services or resources to its users

Network Clients

Computers and software that allow users to request resources shared by and hosted on servers

Local Area Network (LAN)

• A network in a single location

• Definition includes

  • Residential networks with a couple of computers

  • Enterprise networks with hundreds of servers and thousands of workstations

Equipment and cabling used on a LAN

Typically, most of the the _______ is owned and operated by the company or organization using the LAN

Wide Area Network (WAN)

• Networks in different geographic locations but with shared links

• More likely to make use of a service provider network

• Use various types of wireless networking

  • Point to point radio | Cellular radio | Satellite Communication

Telecommunications companies/Telcos

• Companies that operate national telephone networks

• Often operate as ISPs themselves

  • Also make part of their networks available to smaller ISPs

Internet Service Providers (ISPs)

Companies that specialise in providing Internet access

Nodes/Hosts

• Network endpoints

  • A device that connects to a network and can send, receive, or forward information

Network adapter/Network interface card (NIC)

Hardware component that allows a device to connect to a network and communicate with other devices on it

Communications pathways

Implemented using an adapter installed in the host to transmit and receive signals and network media between the interfaces to carry the signals

• Wired Data Connection

• Wireless (Wi-Fi) Data Connection

The 2 types of local network connection

Wired Data Connection

• Use cabling and either electrical signals over copper wire or light signals over fiber optics to connect nodes

• Usually use ethernet to implement these links

Wireless (Wi-Fi) Data Connection

• Use radio signals to transmit signals over the air

• A node usually connects to an access point at a range of up to about 30m

Network Protocol

• Allows hosts to identify eachother’s unique addresses and location

• Defines packet structure

• Example:

  • TCP/ICP

Packet

• “Wrapper” for each data unit transmitted over the network

• Consists of a header and a payload

  • Header — Protocol type | source address | destination address etc

  • Payload — The data

• Made of smaller ____s

True

• Multiple protocols can be used by a network

• The packet from one protocol can be wrapped within the packet from another (encapsulation)

True or False: A network can use multiple protocols