chap2.txt

To exchange of data between a computer and the network to which it is attached.

The transport layer is concerned with data reliability and correct sequencing.

A protocol is the set of rules or conventions governing the way in which two entities cooperate to exchange data.

A PDU is the combination of data from the next higher communications layer and control information.

The software structure that implements the communications function. Typically, the protocol architecture consists of a layered set of protocols, with one or more protocols at each layer.

Transmission Control Protocol/Internet Protocol (TCP/IP) are two protocols originally designed to provide low level support for internetworking. The term is also used generically to refer to a more comprehensive collection of protocols developed by the U.S. Department of Defense and the Internet community.

Layering decomposes the overall communications problem into a number of more manageable subproblems.

A router is a device that operates at the Network layer of the OSI model to connect dissimilar networks.

IPv4.

No, other transport layer protocols, such as UDP, are also used. Some traffic uses no transport protocol, such as ICMP.

IPv4 - 32 bits; IPv6 - 128 bits