IPX – Effects and traffic load

The effect of IPX on our network concerns mostly the increase in bandwidth being used by IPX broadcasts and routing. There are some pluses and some minuses to the bandwidth use by IPX.

IPX is a connectionless Layer 3 protocol, meaning it does not require acknowledgements and therefore uses up less bandwidth. It also uses less bandwidth by not needing to resolve host addresses in the network as often.

SAP is a bandwidth concern, as the constant updates can be frequent and too large. Convergence also takes much longer when using IPX. If the school does decide to implement a Novell server at a future date, this will be a serious consideration. Since we have no Novell servers online right now, this shouldn’t be an issue.

Since we are currently not running any Novell servers within our network, but still want to have IPX running on our network, encapsulation is not as much of an issue as it will be if we do add a Novell server. For that reason, we will use SAP as the encapsulation type on all router interfaces. What type we use in the future will be determined by what version of Novell NetWare we use.

A multiprotocol router is needed to work with both the IGRP routing protocol and the RIP protocol IPX uses.

Our IPX network numbers all begin with 6 and add a letter for each network. For the entire district, each school could be assigned an IPX number

The configuration for IPX is as follows:

Router# config t
Router(config)# ipx routing
Router(config)# interface gi 1/0/0

Router(config-if)# ipx network 6a
Router(config-if)# ipx encap sap

Repeat for all five remaining ports, just changing the interface number and the letter in the network number (ie, 6b, 6c, 6d, etc).

Decision to implement IPX

We have decided to implement IPX routing because of the future potential for a Novell server being added to the school’s network. It generally makes more sense to implement it now, as the network is being designed, than to implement it at a future date, possibly disrupting the network. The overall effect of IPX on the network will be minimal as far as traffic and bandwidth is concerned, and any changes needed to have a Novell server on the network will be minimal. This way, most of the router configuration is done and the networks have already been predetermined.

IPX is in many ways a more efficient use of bandwidth in networks. For this reason, it is likely to be an option for future expansion in the school’s network.