cccar@levels.sait.edu.au (Chris Rusbridge) (06/08/89)
We are thinking of offering network access to external customers via SLIP. This seems to be easy to achieve up to 19,200 bps using the Annex terminal servers and similar devices. However, we'd also like to be able to offer this capability at 48 Kbps. Some questions: a) Is there anything about SLIP that makes this not a sensible choice at 48 Kbps? b) Is there a better way of providing high speed network access? c) What equipment would we need to provide this service? (The best we have been able to come up with so far is a SUN3/150 with SUNlink/IR, plus the fast serial interface, but that's a pretty expensive solution. It would be cheaper by far to put a cisco Hybridge at each end...) Any information gratefully accepted. Chris Rusbridge Academic Computing Service Manager, SA Institute of Technology ACSnet: Chris.Rusbridge@levels.sait.oz [.au] InfoPSI: Chris.Rusbridge@sait.edu.au (DTE 505282622004) Phone: +61 8 343 3098 Fax: +61 8 349 6939 Post: The Levels, SA 5095 Australia
hedrick@geneva.rutgers.edu (Charles Hedrick) (06/12/89)
I don't know of anything that makes 48Kbps SLIP unworkable, assuming that the equipment on both ends can support it. However in general I'd only use SLIP if the cost of real routers is too high. There are advantages to the more conventional synchronous protocols. One is that typically the synchronous controller cards will deal with a whole HDLC packet at once, so that the load on the processor is less. Another is that SLIP is a minimal protocol. Most vendors' synchronous support has provisions for detecting when the line has hung and doing things to reset it, and also for passing multiple protocols (e.g. IP and DECnet) on the same line. You mention needing Sunlink/IR in order to do this on a Sun. We have a SLIP connection between a terminal server and a Sun acting as a gateway, and are not using Sunlink/IR. There's a P.D. SLIP implementation for the Sun. However we're using 9600. It may be that you need something more exotic at 48Kbps.