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Module: Internet and Web Management
1. Explain the different layers of TCP/IP Model? Discuss the purpose of internet layer TCP/IP Suite Protocol? * TCP/IP PROTOCOL SUITE
Communications between computers on a network is done through protocol suits. The most widely used and most available protocol suite is TCP/IP protocol suite.
A protocol suit consists of a layered architecture where each layer represents some functionality which can be carried out by a protocol. TCP/IP is normally considered to be a four layer system. The 4 layers are as follows: * Application layer * Transport layer * Network layer * Data link layer
1. Application layer
This is the top layer of TCP/IP protocol suite. This layer includes applications or processes that use transport layer protocols to deliver the data to destination computers.
Application layer has various protocols that applications use to communicate with the second layer which is the transport layer. Some of the popular application layer protocols are: * HTTP (Hypertext transfer protocol) * FTP (File transfer protocol) * SMTP (Simple mail transfer protocol) * SNMP (Simple network management protocol) etc
2. Transport Layer
This layer provides backbone to data flow between two hosts. It receives data from the application layer above it. There are many protocols that work at this layer but the two most commonly used protocols at transport layer are TCP and UDP.TCP is used where a reliable connection is required while UDP is used in case of unreliable connections.
TCP divides the data (coming from the application layer) into proper sized portions and then passes these chunks onto the network.
Functions of TCP are as follows: I. It acknowledges received packets II. Waits for the acknowledgments of the packets it sent and sets timeout to resend the packets if acknowledgements are not received in time.
The term ‘reliable connection’ is used where it