Classful Routing Protocols are the Routing Protocols# that follow the Fix-Length Subnet Masking#. However, as the networking technologies advanced, most Classful Routing Protocols are phased out in favour of Classless Routing Protocols due to the limitation of Classful Routing Protocols to travel to different Address Classes since the routing update doesn’t include the network mask.
Examples of Classful Routing Protocols:
RIP is a #classful #Distance Vector Routing Protocol that use hop count as metric to find out the routing path. The underlying #algorithm used is the Bellman-Ford Algorithm. If the metric of route is larger than 15, RIP will count it as unreachable. Routing updates are done via broadcast IP address. It can only run on IPv4 networks, in order to run IPv6 one needs to deploy RIPng (RIP next generation) instead. There is a classless implementation of RIP: RIP version 2 (RIPv2)#.
Classless Routing Protocols are the Routing Protocols that don’t follow the Address Classes subnet masking instead favour the Variable-Length Subnet Masking (VLSM)#. All protocols will include network mask when sending the routing information to other Network Device. It is aimed to replace Classful Routing Protocols.