 |
|
The transport layer is used to multiplex and demultiplex data
streams between upper layer application processes as seen in Figure
1-2. The three upper layers of the OSI model, application,
presentation, and session, have been combined in the application
layer in the TCP/IP layered model. Typically, it is more difficult
to determine where a particular upper layer application should be
logically placed. Networks can be designed without knowing which
applications the users are going to be employing. Therefore, the
specific application is not important, just the protocol that the
application will be using. In fact, we will only concern ourselves
with the lower four layers of the OSI and TCP/IP models. |
| |