in chapter 8 we have been learning about networks, the types of networkes we have been looking at are:

• LAN (local area network).
• WAN (wide area network)
• WLAN (wirless lan).

The places that we use LANs are in small offices or even schools.

We use WAN when we are using a wide connection so when we are using the internet.

We use WLAN when we are using a wireless connection with the laptops

There are alot of devices that can connect to the network such as:

• Laptops
• desktops
• printers
• smartphones
• Scanners

Now i am going to talk about the Pros and Cons of using networks:

Pros:

• You can use the network for some back up if you loose your work.
• the peripherals can be shared
• The networks allow access to the documents you need

Cons:

• it is quiet hard to troubleshoot
• all the networks have to be adminisered.

Peer to peer network: is a network where there is no administrator,it is all user contributed, and it cannot be shut down, like certain programmes such as youtube and limewire.

i am now going to talk about Bandwidth:

Bandwidth is the amount of data that can be transmitted within a period of time. When data is sent over a computer network, it is broken up into small chunks called packets. After the other computer or network has recived this data the packet is thrown away. All the packet does is carry the data in small bits till it reaches its destination and then destroyed.

Bandwidth is measured in bits per second.

• bps – bits per second
• kbps – kilobits per second
• Mbps – megabits per second

To remember how many bps or bypes go in a bit or kilobits here is how to remember it:

1 byte is equal to 8 bits. 1 MBps is about 8 Mbps.

Half-Duplex
When data flows in one direction at a time.

Full-Duplex
When data flows in both directions at the same time.

IP addresses:

An IP address is a number that is used to identify a device on the network. every single computer has an ip address, without an ip address then the computer can not connect with the other computers, an ip address to a computer is like a name to us if the computer does not have an ip address it is like not having a name.

IP address 192.168.18.57, the first three octets, 192.168.18. this is an example of an IP address.

IP addresses are divided into the following five classes:

• Class A – Large networks, implemented by large companies and some countries
• Class B – Medium-sized networks, implemented by universities
• Class C – Small networks, implemented by ISP for customer subscriptions
• Class D – Special use for multicasting
• Class E – Used for experimental testing

DHCP: Dhcp stands for Dynamic Host Configuration Protocol, DHCP is a software that allows th IP address to connect to the network devices. Using a DHCP server simplifies the administration of a network because the software keeps track of IP addresses.

Protocols: a protocol basically is a set of rules. Protocols require messages to arrive within certain time so that computers will not wait for messages that might have been lost on the way.

These are the main functions of protocols:

• Identifying errors
• Compressing the data
• Deciding how data is to be sent
• Addressing data
• Deciding how to announce sent and received data

Network types (protocols)

• Ipx/Spx – a protocol used to transport data on a novell netware network
• Netbeui/Netbios- A small, fast protocol designed for a workgroup network that requires no connection to the internet.
• TCP/IP – A protocol used to transport data on the internet
• Telnet – a protocol that uses a text-based connection to a remote TCP/IP computer.
• SMTP – A protocol used to send mail in a TCP/IP network.

ICMP – Internet Control Message Protocol. ICMP is used by devices on a network to send control and error messages to computers and the servers.

Ping – Ping is a troubleshooting tool used to determine basic connectivity, You can also use ping to find the IP address of a host when the name is known.  Ping works by sending an ICMP request to a destination computer or other network devices.

more abouyt networks:

There are many devices that can be used in a network to provide connectivity.

These are the most common devices on a network:

• Computers
• Hubs
• Switches
• Routers
• Wireless access points

Ethernet

Wireless Ethernet standards

802.11

EEE 802.11 is the standard that specifies connectivity for wireless networks. IEEE 802.11, or Wi-Fi, refers to the collective group of standards – 802.11a, 802.11b, 802.11g, and 802.11n.

802.11a
Devices conforming to the 802.11a standard allow WLANs to achieve data rates as high as 54 Mbps.

802.11b
802.11b operates in the 2.4 GHz frequency range with a maximum theoretical data rate of 11 Mbps.

802.11g
IEEE 802.11g provides the same theoretical maximum speed as 802.11a, which is 54 Mbps, but operates in the same 2.4 GHz spectrum as 802.11b.

802.11n
802.11n is a newer wireless standard that has a theoretical bandwidth of 540 Mbps and operates in either the 2.4 GHz or 5 GHz

• P (please) - Physical
• D (dont) – Data-link
• N (not) – Network
• T (throw) – Transport
• S (soggy) – Session
• P (pizza)- Presentation
• A (away) – Application

subnet mask- Defines octects of an IP address that are network / host e.g. 172.16.78.54- 255.255.0.0

Octet- number in an IP address (4 octets in total)

2 ways for a computer to get an IP address: 

1.  Static (typed in by a person)
2. DHCP- dynamic host configuration protocol (given over a network when a computer first turns on.

chapter 7 is all about printer and also scanners. we talked about the diffrent types of printers such as the Dot matrix printer, the thermal printer and also the laser printer and some more. after we learnt about the printers we then moved on to the scanners. we talked about the diffrent types of scanners such as the flatbed scanner, the drum scanner, the all-in-one scanner and the handheld scanner. we also discused things about how quick the laser printer paper comes out and were it would be found which is in big offices and important places. After we learnt this we also start learning about the colours that were in the laser printer which was only four colours, which is black, yellow, magenta and cyan.

While studying the chapter i felt that it was quiet interesting and i think that i done very well as i have learned alot on printers and scanners. when we first started the chapter i found it very difficuilt and i did n ot no anything about printers and scanners. the best thing about the chpter was when we were doing the practical, as now i have learnt how to download the printer on to the computer. that was the best and most exiting bit about it. i also enjoyed when sir brang in the dot matrix printer and showed us how it worked even though it was not that good.

bas ed on this chapter i could have done better work in my homework. and i could of listend a bit more.

in chapter 8 would like to do very wellas it is about networking. i would like to do well and improve my grade from chapter 7. i hope to work very hard and do unbelevible work. the grade i am going to be going for in chapter 8 would be at least a C.

i am going to show you how to geta lexmark printer to work, and i am going to show the step by step ways to do it:

step 1: before you start you have to make sure the printer is plugged into the computer.

step 2: locate your printer on the website and it will allow you to install.

step 3: after you find your printer choose the file you want and just click the download button

step 4: after you clicked the download button the downloading process should begin

step 5: after the download process is complete the tab should appear saying run then you click that button

lexmark is another printer and here are some facts about it.

• when you print black, it prints up to 2400 x 1200 dpi
• when you print in colour, it prints up to 4800 x 1200 dpi
• maxium print speed in black is up to 22 ppm
• maxium print speed in colour is up to 15 ppm
• the ink catridges cost about £35 for both colour and black ink

the life span for the lexmark x3350 is about 8 years.

There are two main printers availible today they are called a laser printer and a inkjet printer. a laser printer is a very quick printer, it prints at least 3 pages per second but it could cost quiet a bit and you would mostly see them kind of printers in companys or a office as it prints things very quick. the laser printer contains 4 colours them 4 colours are yellow, redish pinish, blue and manjenter. to get other colours you will have to mix the colours up for example if you wanted to get a green you will have to mix blue and yellow. A ink jet printer is what most people have got and it is very common but the downside of the printer is that it takes a very long time to print one sheet of paper about 3 minites.

The prices of the printers depends on the cappacity and speed of the printer. factors of relibilty include: warrenty, scheduled servicing and mean time between failures or for short (MTBF) this is a very important thing to remember.

another important thing to remember is:

 Here are some Total Cost of Ownership or for short (TCO):

• initial perchase price
• costs of supplies such as paper and ink
• price per page
• maintanence costs
• warrenty costs
• the amount of material to be printed
• the expected lifetime of the printer