Dynamic Routing Protocols

A routing protocol is the communication form used to share network information between connected routers.

Dynamic routing protocols in contrast to static routing have several advantages, here are a few of them:

Although there are advantages to dynamic routing, when designing a network and the appropriate routing solution, the simplest is always the best. Sometimes static routing is the most appropriate routing solution over dynamic routing, especially if the size of the network is small or the hierarchical structure and internetwork routing points are simple.  I would balance the following factors when deciding which is the most appropriate:

• The complexity of the proposed network (e.g. number of loca and remote sites, routers, internal and external networks).
• Administrative overhead i.e. do network topology changes occur often or is the network generally static.
• Technical level of those responsible for the network management i.e. depending on the technical expertise of the engineers responsible to manage and troubleshoot the network would influence how complex a routing solution to design.
• Future growth, if this is known whether the network or the organisation is likely to grow in the future.

There are a variety of routing protocols, each with their own characteristics and which to select will depend on a variety of criteria including equipment being used, size of network, security, amongst others.  Here are a list of widelky known and used routing protocols:

• EIGRP – IGP and Cisco proprietary
• RIP – IGP and legacy
• OSPF
• BGP