It is essentially a cut down version of RIP-2 that consumes much less bandwidth,
but for all intents and purposes includes the same routing information. RIP-2
includes a lot of nulls in its data and takes up more bytes than is needed to transfer
each routing item.
It would be quite easy to retro-fit RIP98 to an already existing RIP-2 program.
Its been in the ax25-utils for years as rip98d.
Jonathan HB9/G4KLX