ABSTRACT
To assure that the required bit rate is made available to the application layer, the transport layer may group multiple network layer connections into a single application layer connection. Let us consider the case where the network layer has a 512 kbps connection established, and the application layer is requesting a 1024 kbps connection. In this situation, the transport layer may establish a second 512 kbps network connections and, in a transparent manner, o›er a 1024 kbps connection to the application layer. Similar function may be o›ered when the application layer is requesting a datagram size higher than the maximum transmission unit (MTU). In this situation, the transport layer performs the segmentation (at the transmitting side) and reassembling (at the receiving side) of data, such that it †ts within the MTU.
