Topic > The OSI and TCP/IP Models:

Today I will compare and explain each of the layers in both the OSI and TCP/IP models. First I will talk about the OSI model. The OSI model (open systems interconnection model) has 7 layers from the physical layer to the application layer. The first layer, the physical layer, involves the movement of data across a network. This layer will also allow the hardware to send and receive data via a network operator (e.g. three, EE). A device that connects at this level will be a hub. The second layer, the data link layer, consists of creating links across the network, this action is performed by collecting information and sending data in the form of frames. Ideation on this level would include bridges and switches. Layer three is the network layer, this layer is used to create the addresses and path in which the data travels. This then ensures that the data is sent to the right place. An example of this layer would be IP addresses. At this level the device that will be connected is the Router. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an Original Essay The next layer, the transport layer, is designed to handle the data packets being sent and then make sure they are delivered to the correct location. This layer will also check for any data corruption that may occur during transit. The fifth level, i.e. the session level, is responsible for managing conversations. This will involve setting up and ending conversations. This also includes connecting and even reconnecting after the connection has been lost or interrupted. The sixth level, the presentation level, is often part of the operating system. Its job is to convert data entering and leaving the network into a readable format. The last layer of the OSI model is the Application layer, this layer is used to identify partners and this allows the data sent to be opened and displayed to the user. The devices that would connect at this level would be PCs, servers, phones and even hosts. The TCP/IP (Transmission Control Protocol/Internet Protocols) model has only 4 layers from Network Access to Applications layer. The TCP/IP model is integrated into every computer and is necessary to access the Internet. The lower layer, which is the network access layer, contains details about how information is sent across the network. For example, the way data bits are sent, this layer also deals with hardware devices such as fiber optics or Ethernet cables. The next layer is the IP layer, this layer is used to convert the data being sent into IP datagrams and this will then allow the data to be sent across the network. The next layer is the TCP layer, this layer is intended to allow devices to connect, host conversations and share data across the network. The last layer, the application layer, is at the top of the model and is designed to define the TCP/IP protocols and also determine how each program running on the network is hosted. An example of this would be the DNS (domain naming system). Next I'll talk about the differences between each model and explain why some layers are missing from the TCP/IP layer. First I will talk about the missing layers in the TCP/IP model. The missing layers are not missing but are combined into one layer, the presentation layer and session layer of the OSI model have been combined together to create the application layer. This also applies to the data link and the physical layer, which are located in the TCP/IP model.