stp, sctp and tcp

It was during a discussion about the migration strategies for the R4/R99 and some LTE test gear that it was disclosed a new STP (Signalling transfer point) would be integrated at around the same time the new core would be coming 'live'. Some of the MPLS vendor's guys have not worked on a mobile core before so it's a learning experience for everyone.

It got more interesting when a 'new' protocol SCTP was mentioned as being in extensive use. One of the guys is a new ccie and as you can imagine his TCP knowledge is still fresh in his mind. It thoroughly bewildered him why SCTP was even necessary in the first place. We white boarded quite a number of reasons with explanations (it makes it easier for the migration if we're all semi clueful of what's going on on the network) so we tend to stop 'everything' and explain alot.

rfc2960 (http://www.ietf.org/rfc/rfc2960.txt) gives a very clear explanation. Please head over there to see why SCTP is necessary for some applications.

I also expect alot more implementations and use of SCTP over the coming years.well at least I expect it at work. It has a mature socket API so writing applications for this is not a big problem for experienced and novice programmers who dont mind putting in some time.

At work I've changed some apps to sctp to gain the 'multihomning advantage', other than that there's really nothing to get excited about. It's however good to have an idea that such a protocol exists, if nothing else, it makes for exciting 'beer' talk.