NetWork Design Question 1a.) In writing a letter to a Friend, what do you hace to do to get the letter to your friend. List all the steps and ways. 1b.) Relate the stages of letter transaction to the layers of the internet. Solution In writing a letter to a Friend, the following 5 steps do you face to get the letter to your friend. 1) Application layer: TCP/IP: A user retrieves a Web page from a server in somewhere by typing a URL into a browser and clicking the enter key. The server receives the request, finds the page on its hard drive and sends it back to the user. Neither the user nor the client or server software is aware of the way the messages were delivered. There are many application layer protocols. 2) Transport layer: TCP/IP: Transport layer software establishes a connection between a client and server then monitors that connection for errors. It also slows transmission if it gets too fast to handle at the other end. Transport layer software is not concerned with how the data is actually moved from one point to the other that is the responsibility of lower level software. There are two transport layer protocols TCP (reliable) and UDP (unreliable, but fast). If TCP tries repeatedly and errors persist, it informs its \"boss,\" the application program. 3) Internet layer: TCP/IP:Internet layer programs move data between networks. IP is the internet layer protocol. IP software ignores the data, and it does the same thing with a packet whether it comes from the friend or your mother. Once the data gets to its destination local area network (LAN), it is handed over to data link layer software or firmware for delivery to the proper computer. 4) Data link layer: TCP/IP:Data Link layer programs move (incoming and outgoing) data within LANs. Ethernet is the most common data link protocol. A data link program is not concerned with how outgoing data will be handled once it leaves the LAN or how incoming data got there. That is the responsibility of the internet layer software. 5) Physical layer: TCP/IP:Physical layer protocols specify the means of representing ones and zeros (bits). The method of transmitting them between two points using wire, radio, fiber, etc. is also specified. There are many ways to make ones and zeros and many ways to transmit them so there are many physical layer protocols..

1. NetWork Design Question
1a.) In writing a letter to a Friend, what do you hace to do to get the letter to your friend. List all
the steps and ways.
1b.) Relate the stages of letter transaction to the layers of the internet.
Solution
In writing a letter to a Friend, the following 5 steps do you face to get the letter to your friend.
1) Application layer:
TCP/IP: A user retrieves a Web page from a server in somewhere by typing a URL into a
browser and clicking the enter key.
The server receives the request, finds the page on its hard drive and sends it back to the user.
Neither the user nor the client or server software is aware of the way the messages were
delivered. There are many application layer protocols.
2) Transport layer:
TCP/IP: Transport layer software establishes a connection between a client and server then
monitors that connection for errors.
It also slows transmission if it gets too fast to handle at the other end. Transport layer software is
not concerned with how the data is actually moved from one point to the other that is the
responsibility of lower level software. There are two transport layer protocols TCP (reliable) and
UDP (unreliable, but fast).
If TCP tries repeatedly and errors persist, it informs its "boss," the application program.
3) Internet layer:
TCP/IP:Internet layer programs move data between networks. IP is the internet layer protocol.
IP software ignores the data, and it does the same thing with a packet whether it comes from the
friend or your mother.
Once the data gets to its destination local area network (LAN), it is handed over to data link layer
software or firmware for delivery to the proper computer.
4) Data link layer:
TCP/IP:Data Link layer programs move (incoming and outgoing) data within LANs.
Ethernet is the most common data link protocol. A data link program is not concerned with how
outgoing data will be handled once it leaves the LAN or how incoming data got there. That is the
responsibility of the internet layer software.
5) Physical layer:
TCP/IP:Physical layer protocols specify the means of representing ones and zeros (bits).

2. The method of transmitting them between two points using wire, radio, fiber, etc. is also
specified. There are many ways to make ones and zeros and many ways to transmit them so there
are many physical layer protocols.