Introduction The transport layer is the fourth layer of the OSI model. The transport layer provides a peer-to-peer and end-to-end connection between two processes on remote hosts. The transport layer offers connection-oriented and connectionless reliability depending on the application. The transport layer takes data from the application layer, then breaks it into smaller segments, numbers each byte, and passes it to the network layer for delivery. The most common transport layer protocols are Transmission Control Protocol (TCP) and the connectionless User Datagram Protocol (UDP). Both protocols are connection oriented. Other transport layer protocols say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original essayATP: AppleTalk Transaction ProtocolCUDP: Cyclic UDPDCCP: Datagram Congestion Control ProtocolFCP: Fiber Channel ProtocolIL: IL ProtocolMPTCP: Multipath TCPRDP: Reliable Data ProtocolRUDP: Reliable User Datagram ProtocolSCTP: Flow Control Transmission ProtocolSPX: Sequenced Packet ExchangeSST, Structured Stream TransportTCP : transmission control protocolμTP: micro transport protocolAny host can have multiple applications communicating across the network. Each of these applications will communicate with one or more applications on remote hosts. It is the responsibility of the Transport layer to maintain the multiple communication flows between these applications. Topic Analysis Because each application creates a stream of data to send to a remote application, this data must be prepared to be sent across the media in manageable chunks. Transport layer protocols describe services that segment this data from the Application layer. This includes the encapsulation required on each piece of data. Each application data requires headers to be added at the transport layer to indicate which communication it is associated with. At the receiving host, each piece of data can be routed to the appropriate application. Furthermore, this individual data must also be reconstructed into a complete data stream that is useful to the Application layer. Transport layer protocols describe how Transport layer header information is used to reassemble data into streams to pass to the Application layer. To pass data streams to the appropriate applications, the Transport layer must identify the destination application. To achieve this, the Transport layer assigns an application identifier. TCP/IP protocols call this identifier a port number. Each software process that needs to access the network is assigned a unique port number on that host. This port number is used in the transport layer header to indicate which application that data is associated with. The transport layer is the link between the application layer and the lower layer which are responsible for network transmission. This layer accepts data from several conversations and transmits it to lower layers as manageable chunks that can eventually be multiplexed across media. Applications do not need to know the operational details of the network in use. Applications generate data that is sent from one application to another, regardless of the type of destination host, the type of media on which the data must travel, the path taken by the data, the congestion on a link, or the size of the net. Furthermore, the lower layers are not aware that there are multiple applications sending data over the network. Their responsibility is to deliver the data to the appropriate device. The transport layer.