Cisco IP Routing Protocols: Trouble Shooting Techniques (Charles River Media Networking/Security)

Connection-oriented protocols ensure that the sequence of data packets is the same at the source and destination nodes. These protocols are also called reliable protocols.

Connectionless protocols do not send data packets in the same sequence at the source and destination nodes. These protocols are called unreliable protocols.

Examples of connection-oriented protocols are Type 2 service of IEEE 802.2, ATM, TP0, TP1, TP2, TP3, and TP4, and TCP.

Examples of connectionless protocols are Type 1 and 3 services of IEEE 802.2, CLNP, IP, and FST.

The Data-link layer uses three types of protocols: PPP, SDLC, and HDLC.

The primary protocol used on the Network layer is IP, which routes data packets from the source to the destination node in a network.

The Transport layer of the OSI model uses TCP and UDP protocols for transferring data through the network. TCP is responsible for the connection-oriented data transfer, whereas UDP provides connectionless data transfer.

The Session, Presentation, and Application layers are concerned with the applications accessed by end users. Examples of protocols residing on these layers are RIP, IGRP, and EIGRP.