The Red Dot

Chapter 8

Mac address-A mac address is a serial number affixed with a network adapter here is a picture that shows you what it looks like-

IP Address-IP stands for internet protocol and it is a unique number that is assigned to a computer when it is using the internet but when you turn off your computer that IP address that you was using is given to another computer because there isn’t enough IP address for every single computer in the world.

Subnet mask- A subnet mask is to identify a small network inside a large network.It blanks out a part of an IP address and tell you were it is.

HUB- A hub sends information to all of the computers so it is not as good as a switch because it creates to much internet traffic.

Switch- A switch is a sort of like a hub but it remembers computers IP address so that if you need to send something then it goes to that computer instead of going to all of the computers also you can have more computers connected up to the switch so it is useful for large networks such as school and business.

Router- A router is a device that interconnects two or more computers networks and shares packets of data between them also it provides an internet connection for the computers that it is connected to.This is a picture of a cisco router

DHCP-DHCP stands for dynamic host configuration protocol and what a DHCP server does is assign an IP address automatically so that you do not have to do manually and this is good for work and places and big business because of the amount that the person that is setting up the computers has to do is enormous and if the person who is setting the computers up he would have to go round to every single computer and manually configure an IP address , It is also quick and efficient.You can also set a start IP address and an end IP address and what this is, is the DHCP server starts giving IP address that start from the number that you put and it stops giving IP address’s at the number that you put in at the end IP address and in this picture you can see this.

LAN- LAN stands for local area network and it gives an internet connection to a small group of computers and it is not used for large scale it is most commonly used in the home because it is easy to set up and configure also it is not very expensive so that is why it is so popular.

LAN architectures- LAN architectures are  is the way the network is layed out and the most common ones are a ring, bus and an star.

A ring is all the computers network cards working as repeaters and there is no starting or end point  also each node will repeat each signal that it received regardless of it’s destination, The destination station recognises its address and copies the frame and into a local stream as it goes by.

A bus is were all of the connections are connected to one cable as a result of this every node on that cable see’s a transmission from every other station at the end of each bus is a thing called a terminator which asorbs any signal and then removing it from the bus IEEE 802.3) is the protocols used for this type of LAN.

A star is were all the stations are connected by a cable or wireless and the the thing producing the connection is allways in the middle in a star although the arrangement is physically a star it is logically a bus because because the central node is acting like a switch, An incoming frame is processed in the node and then retransmitted on an outgoing link to the destination Ethernet protocols IEEE 802.3 are often used in star LAN.

NIC devices- A NIC is a network interface card and is required to connect to the internet

• Installing a NIC (Networking Interface Card) When installing a new driver be sure to disable all virus protection software because the protection software may pick it up as a potential attack and if this happens some of the software may be installed incorrectly and only one driver should be installed at one time  because some updating processes may conflict.

• Also another safety precaution is to close all applications running because they also may conflict with the update or install because if your updating and you still have your browser open or you are downloading something it may install incorrectly because of the conflict and will in effect not work.

• To find the NIC you will need to go into Device manger and then find your network card and it should look something like this
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• VoIP- VoIP means Voice over IP and what it does is it sends your voice in a IP packet to the person that you are calling and this is totally dependant on the internet connection so if your internet connection fails you will not be able to make any calls or receive them.
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• OSI model-There are seven layers to the OSI model and these layers are: pysical , Data link, network, Transport, session, Presentation, application.
• Physical this defines all the electrical specifications for devices.
• Data link it provides physical addressing and media access procedures .
• Network this is responsible for logical addressing and the domain of routing.
• Transport provides reliable transport and flow control across a network, It is also is responsible for sending off packets of data.
• Session establishes, manages and terminate the connections between the local and remote application.
• Presentation transforms data formats to provide a standard interface for the application layer.
• Application is responsible for network services to applications.
• If you go onto any website you will receive a packet.

• Broad band-Broadband is a technique used to transmit signals using multiple frequency’s over one cable