UNIT 10
Unit 10 P1 - Explain how networks communicate
Computer networks: LAN, WAN, and wireless
LAN stands for local area network which is a group if computers which are afliated devices which
will share usual communicatons line or a wireless connecton to the server. Usually, a LAN involves
peripherals and computers which have a connecton to the server with a clear, geographic area.
WAN stands for wide area network which is given through a telecommunicatons network which
connects many local area networks. In a business, WAN may have made up of connectons to a
business headquarters e.g. Usually, a router is used to connect LANS to a WAN, although there are
other devices which are multfunctonal which can be used. Wireless network are computer
networks which do not have connecton of cables from the device to the network. Wireless networks
will use radio waves to obtain a connecton with the devices, for example a smartphone which has
Wi-Fi.
Network topologies: Star
A star network topology is usually used on home environments and Local area networks. Within a
star network, computers have a connecton with the centralized connecton point which is usually
referred to as the hub node (Which is usually a network hub, switch or a wireless router.) Host
devices are commonly connected to hub using a Ethernet cable. Usually in most cases, the star
network will need more cables, which can be expensive, although the star network is more tolerant
for redundancy, which means if a cable gets damaged, the rest of the LAN will not go down.
Network topologies: mesh
The mesh topology is based on having many pathways. Data which will be sent from a mesh
topology will not be required to take a pre-determined route. Mesh topology has the opton of many
different routes to be able to get from the source to the desired destnaton. In many WAN’ss the
mesh model is the most common.
The advantage of a mesh topology is that during a tme there is a high trafc volume, the network
will not be slowed down as the data has many routers to travel from. It doesn’st mater if other
components fail as the network will not go down. Although, the mesh topology has a high setup
cost, and maintaining such a topology is difcult and expensive.
Network topologies: bus
A bus network will use one backbone, to connect all the devices on a network. The cable is the
procedure of transmission for the devices to communicate from one device to another. The devices
have connecton to the network using a connector which is singular interface. When a device from
the network wants to communicate with another one it will send a message to the network, which
,can be viewed from all devices which are connected to the network, but will only be processed by
the device which is intended. This methodology is simple to install, and requires a small amount of
cables which will be cheap to maintain, although if many devices have a connecton to the network,
the network could become unstable, which could lead to signal failure.
Network topologies: Tree
A tree network is when two or more star networks are connected to each other. Each individual star
network is a LAN which there will be a central server or computer which the workstaton computers
are connected to. The central computers from the star networked will relate to a bus cable. If a cable
failure occurs in the star networks, it will isolate the workstaton which links to the central computer
of the star network, although only that workstaton will become single. The rest of the workstatons
will work as normal, although they will not be able to make a connecton or communicate with the
workstaton with had become isolated. If a central computer was to go down the entre network
served will suffer with performance issues, or total failure, but the rest of the network will work as
intended.
Network topologies: Ring
Within a ring network each device has a connecton to two other devices which creates a ring to let
the signal to go around. Each individual packet of data will travel only in one directon and each of
the devices will receive the packet untl the destnaton device receives it.
network service: packet switched
Packet switched outlines the type of network which small units of data which is known as ‘packets’s
are routed from a network based on the address of the destnaton contained in packets.
Communicaton which is broken by packets lets the data path to be shared with users in the
network. Majority of trafc on the internet uses packet switching.
network service: ISDN
ISDN stands for integrated services digital network which is known as a digital standard for
telephone networks. Which is known for many kinds of communicaton services which transmit from
networks. ISDN also lets the use of packet switch or data transmission of circuit switch. In some
countries, ISDN technology has replaced analogue telephone networks.
Network services: multplexed
Multplexing is a method of giving out various signals or streams of informaton from
communicatons which connect at the same period of the lone, complex signal. Networks may use
complexing to make network devices to talk to other network devices without requiring having a
dedicated connecton between the pair. Another reason for networks to use multplexing is to make
the expensive resource stretch further.
Network services: ATM
ATM is a fast networking standard which is made to allow voice and data communicatons. ATM is
usually utlized by Internet service providers for long-distance networks which are private. ATM uses
the second layer of the OSI model.
Network services: WAP
, WAP stands for wireless applicaton protocol, which is known as a secure specifcaton which allows
users to get into informaton quickly with wireless devices, for example tablet computers. WAP
supports majority of wireless networks. WAP is also supported by all kinds of operatng systems.
Broadband
Broadband is known to be a high bandwidth connecton to the internet. Broadband is simple and
quicker to use in comparison to the modern telephone, because informaton can be downloaded
much faster, as well as being sent. Broadband can be transferred by phone line, cable or satellite.
Which requires high amount of informaton be transferred to the device. Broadband can make the
internet from home much simpler, quicker, and efcient.
Network operatng system (NOS)
Network operatng system is also known as NOS. Networking operatng system has features and
functons for connectng devices and computers to a Local area network. Network operatng system
is usually known for sofware which improves a simple operatng system. One example of a network
operatng system would be Microsof windows server i01i.
Network connecton sofware
Network sofware are made specifcally to make it simple to setup, monitor and manage computer
networks. Network sofware will be used for networks of all sizes, small home networks to
enterprise networks.
Access methods: CSMA/CD
CSMA/CD is a contenton protocol. Networks which use CSMA/CD procedure is easy to setup, but
will not contain deterministc transmission characteristcs. CSMA/CD stands for carrier sense
multple access / collision detecton which are guidelines for resolving how a network device will
react when two devices will try to use the data channel at the same tme.
CSMA/CA
CSMA/CA stands for carrier sense multple access / collision avoidance. Which a network protocol
which reads a network to prevent collisions. In comparison to CSMA/CD, CSMA/CD will work with
sort out the issues when network transmission collision is detected. CSMA-CA will add to network
trafc, since before any data is transmited, a broadcast to the network will be required to check for
collecton, as well as instruct devices not to broadcast.
Token passing
Token passing is a channel access method. Token passing uses bits to give permission for a device to
transmit from a network. The device which contains the ‘token’s will be able to put data to the
network. When the transmission process is fnished. The token will be moved to the next device
within the topology.
Network components: servers
Is a computer or device within a network which will maintain network resources. Severs are usually
dedicated which means they will not carry out any other work, with the excepton of the sever task.
Unit 10 P1 - Explain how networks communicate
Computer networks: LAN, WAN, and wireless
LAN stands for local area network which is a group if computers which are afliated devices which
will share usual communicatons line or a wireless connecton to the server. Usually, a LAN involves
peripherals and computers which have a connecton to the server with a clear, geographic area.
WAN stands for wide area network which is given through a telecommunicatons network which
connects many local area networks. In a business, WAN may have made up of connectons to a
business headquarters e.g. Usually, a router is used to connect LANS to a WAN, although there are
other devices which are multfunctonal which can be used. Wireless network are computer
networks which do not have connecton of cables from the device to the network. Wireless networks
will use radio waves to obtain a connecton with the devices, for example a smartphone which has
Wi-Fi.
Network topologies: Star
A star network topology is usually used on home environments and Local area networks. Within a
star network, computers have a connecton with the centralized connecton point which is usually
referred to as the hub node (Which is usually a network hub, switch or a wireless router.) Host
devices are commonly connected to hub using a Ethernet cable. Usually in most cases, the star
network will need more cables, which can be expensive, although the star network is more tolerant
for redundancy, which means if a cable gets damaged, the rest of the LAN will not go down.
Network topologies: mesh
The mesh topology is based on having many pathways. Data which will be sent from a mesh
topology will not be required to take a pre-determined route. Mesh topology has the opton of many
different routes to be able to get from the source to the desired destnaton. In many WAN’ss the
mesh model is the most common.
The advantage of a mesh topology is that during a tme there is a high trafc volume, the network
will not be slowed down as the data has many routers to travel from. It doesn’st mater if other
components fail as the network will not go down. Although, the mesh topology has a high setup
cost, and maintaining such a topology is difcult and expensive.
Network topologies: bus
A bus network will use one backbone, to connect all the devices on a network. The cable is the
procedure of transmission for the devices to communicate from one device to another. The devices
have connecton to the network using a connector which is singular interface. When a device from
the network wants to communicate with another one it will send a message to the network, which
,can be viewed from all devices which are connected to the network, but will only be processed by
the device which is intended. This methodology is simple to install, and requires a small amount of
cables which will be cheap to maintain, although if many devices have a connecton to the network,
the network could become unstable, which could lead to signal failure.
Network topologies: Tree
A tree network is when two or more star networks are connected to each other. Each individual star
network is a LAN which there will be a central server or computer which the workstaton computers
are connected to. The central computers from the star networked will relate to a bus cable. If a cable
failure occurs in the star networks, it will isolate the workstaton which links to the central computer
of the star network, although only that workstaton will become single. The rest of the workstatons
will work as normal, although they will not be able to make a connecton or communicate with the
workstaton with had become isolated. If a central computer was to go down the entre network
served will suffer with performance issues, or total failure, but the rest of the network will work as
intended.
Network topologies: Ring
Within a ring network each device has a connecton to two other devices which creates a ring to let
the signal to go around. Each individual packet of data will travel only in one directon and each of
the devices will receive the packet untl the destnaton device receives it.
network service: packet switched
Packet switched outlines the type of network which small units of data which is known as ‘packets’s
are routed from a network based on the address of the destnaton contained in packets.
Communicaton which is broken by packets lets the data path to be shared with users in the
network. Majority of trafc on the internet uses packet switching.
network service: ISDN
ISDN stands for integrated services digital network which is known as a digital standard for
telephone networks. Which is known for many kinds of communicaton services which transmit from
networks. ISDN also lets the use of packet switch or data transmission of circuit switch. In some
countries, ISDN technology has replaced analogue telephone networks.
Network services: multplexed
Multplexing is a method of giving out various signals or streams of informaton from
communicatons which connect at the same period of the lone, complex signal. Networks may use
complexing to make network devices to talk to other network devices without requiring having a
dedicated connecton between the pair. Another reason for networks to use multplexing is to make
the expensive resource stretch further.
Network services: ATM
ATM is a fast networking standard which is made to allow voice and data communicatons. ATM is
usually utlized by Internet service providers for long-distance networks which are private. ATM uses
the second layer of the OSI model.
Network services: WAP
, WAP stands for wireless applicaton protocol, which is known as a secure specifcaton which allows
users to get into informaton quickly with wireless devices, for example tablet computers. WAP
supports majority of wireless networks. WAP is also supported by all kinds of operatng systems.
Broadband
Broadband is known to be a high bandwidth connecton to the internet. Broadband is simple and
quicker to use in comparison to the modern telephone, because informaton can be downloaded
much faster, as well as being sent. Broadband can be transferred by phone line, cable or satellite.
Which requires high amount of informaton be transferred to the device. Broadband can make the
internet from home much simpler, quicker, and efcient.
Network operatng system (NOS)
Network operatng system is also known as NOS. Networking operatng system has features and
functons for connectng devices and computers to a Local area network. Network operatng system
is usually known for sofware which improves a simple operatng system. One example of a network
operatng system would be Microsof windows server i01i.
Network connecton sofware
Network sofware are made specifcally to make it simple to setup, monitor and manage computer
networks. Network sofware will be used for networks of all sizes, small home networks to
enterprise networks.
Access methods: CSMA/CD
CSMA/CD is a contenton protocol. Networks which use CSMA/CD procedure is easy to setup, but
will not contain deterministc transmission characteristcs. CSMA/CD stands for carrier sense
multple access / collision detecton which are guidelines for resolving how a network device will
react when two devices will try to use the data channel at the same tme.
CSMA/CA
CSMA/CA stands for carrier sense multple access / collision avoidance. Which a network protocol
which reads a network to prevent collisions. In comparison to CSMA/CD, CSMA/CD will work with
sort out the issues when network transmission collision is detected. CSMA-CA will add to network
trafc, since before any data is transmited, a broadcast to the network will be required to check for
collecton, as well as instruct devices not to broadcast.
Token passing
Token passing is a channel access method. Token passing uses bits to give permission for a device to
transmit from a network. The device which contains the ‘token’s will be able to put data to the
network. When the transmission process is fnished. The token will be moved to the next device
within the topology.
Network components: servers
Is a computer or device within a network which will maintain network resources. Severs are usually
dedicated which means they will not carry out any other work, with the excepton of the sever task.
