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New Member

Urgent Questions

Good day, This is my first contact with the quarrel list and would like to share my knowledge with vocês and also it would like to add new knowledge. It follows below a battery of questions that I am with doubts:

1) When it is said that in the application layer it establishes the availability of the intended processes of communication, it synchronizes and it establishes the agreement on the procedure for the recovery of errors and the control of the integrity of the data. It is if relating what! accurately? Since the session layer is that it establishes and management and it finishes sessions between hosts that they are communicated. E the layer of enlace is responsavel for encrementar at the moment of the encapsulamento in its session the CRC, determined where if it initiates and it finishes pacotede given, and in case that some if embezzles in the passage, the transport layer is that it is puted in charge of the solicitação/envio if at the moment of the assembly of the message will have the lack of a piece of it. The activity of each layer, is not separately?

2) In the reality that address is used in the transit confiavel of data atraves of the net, address MAC or atribuido address IP to host?

3) For what! in a byte it has 8 bits, and not another number any?

4) In the presentation of Capitulo 1 it has one brief explanation that in the WAN's; "IT SUPPLIES to CONECTIVIDADE IN INTEGRAL TIME and PARTIAL TIME" That it differs from the LAN's; "IT SUPPLIES to UNINTERRUPTED CONECTIVIDADE To dedicated the LOCAL SERVICES" the two could not supply to conectividade initerrupta using links? Or the reason of if offering a comunicção for partial time must oa high dedicated cost of one link in WAN's?

5) In the text of the last lesson it was cited that the "TOPOLOGY", is one of the factors that influence in the Troughuput. How this factor can determine the width of band? The text is mentioning the capacity to it of transference of the handle? Or to the made use form of the handles in the net?

In I wait it,


New Member

Re: Urgent Questions

I have tried as best as possible to answer your questions as I understood them. I have provided links that will get you started in getting more information and insights into the theory of networking, wide area networks.

1. Functions of layers the OSI model. The following link provides an illustration of the layers and functions of each. Packets are usually traverse down the layers and encapsulated, and on the receiving end, they go up the layers and decapsulated. Each layer hands-off packets to the next.:,,sid7_gci523729,00.html

2. MAC address and IP address in packet transmission over the internetworks:,,sid7_gci212506,00.html

3. Why are there 8 bits in a byte?

4. Packet switched networks are cheaper in cost than dedicated since the media is shared by other subscribers.

5. The bandwidth (or throughput) of a wide area network link is determined by the service provider, depending on the service subscribed. It can be limited to the characteristics of the physical media over which packets transmitted.

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