Order in the court!!
Protocols bring order to the chaos of communication. Without protocols, there would be no order when communicating (sending and receiving). There have to be procedures for acknowledging that what is sent was received, never received, or retransmission if not received.
Computers communicate with each other using network protocols to carry and encapsulate their bits and bytes converted to electronic impulses to its final destination.
Network Protocols are broken down into two types; routing protocols and routed Protocols.
A routing protocol uses algorithms to determine the optimal path (route) to forward a packet to its intended destination. It specifies how routers communicate with each other, distributing information that enables them to select routes between any two nodes on a network.
Routing protocols can be classified into different groups based on their characteristics. The characteristics of a routing protocol are:
- Purpose: RIP, EIGRP, OSPF, and IS-IS
- Operation: Distance vector protocol, link-state protocol, or path-vector protocol
- Behavior: Classful (legacy) or classless protocol
The purpose, behavior, and operation of a routing protocol is further broken down by the following:
- Distance Vector – Distance Vector means that the routes are advertised by providing distance and vector. The distance is how far it is to the destination network and is based on metrics such as hop count, cost, bandwidth, and delay. It does not have the knowledge of the entire path to the destination.
- Classless – Classless routing protocols evolved from legacy classful (RIPv1 and IGRP) routing protocols. Classless routing protocols include subnet mask information in the routing updates whereas classful does.
- Link-state – Link-state state creates a complete topological view of the network by gathering information from all other routers.
Some examples of routing protocols and their classifications are:
- EIGRP: IGP, distance vector, a classless protocol developed by Cisco
- OSPF: IGP, link-state, classless protocol
- IS-IS: IGP, link-state, classless protocol
- BGP: EGP, path-vector, classless protocol
A routed protocol is a protocol by which data can be routed. Some examples of routed protocols are:
- IP: Internet Protocol (IP) is the principal communications protocol in the Internet protocol suite for relaying datagrams across network boundaries.
- IPX: IPX (Internetwork Packet Exchange) is a networking protocol from Novell that interconnects networks that use Novell’s NetWare clients and servers. IPX is a datagram or packet protocol.
- AppleTalk: A discontinued proprietary suite of networking protocols developed by Apple Inc.
To better understand routed protocols, we will take a look at the OSI Layer.
The OSI layer is the framework that brings order to all protocols. Everything in its place. Nice and neat. Its purpose is to offer guidance to developers and network vendors with the communications hardware and software applications that they create can interoperate with each other.
Now that we have a general understanding of communications and protocols, we can now move on to the last installment of this blog series, networking.