On 1.5.2012 7:26, Dave McGuire wrote: On 04/29/2012 04:14 AM, Kari Uusim ki wrote: DECnet must have been around at least from 1993, because the DECbrouter90's, which were practically Cisco routers in a DEChub90 module, were introduced in 1993. And they used IOS. Did you mean DECnet support in IOS, or DECnet itself? DECnet itself dates to the mid-1970s. I meant the DECnet support in IOS. I don't have older documentation than from the DECbrouter90 initial manuals which were dealing with IOS 9.14. Therefore I don't know how long time ago DECnet became supported in IOS. What I haven't found out is when the IP tunnels were introduced in the IOS. It seems to be in IOS 11.2. So it is included in all recent versions, but the Cisco 2500's have limited flash and RAM capabilites. Therefore the recent IOS's cannot be used with older hardware. I suppose the IOS 11.2 should be sufficient for tunneling DECnet over IP. I'll bet much older releases than that would support this. The 9.14 documentation doesn't mention other kind of tunneling than Serial tunnneling which was used for IBM protocols. Maybe other protocols can be tunneled as well. Don't know and haven't tested. The IOS Reference guide for IOS V11.2 does describe IP tunneling so it is included in that version for sure. I have to check which versions I have on my 2500's. Most probably they have an IP-only version of the IOS. I bought the 2500's cheap from a local broker a few years ago. I've got lots of IOS images if needed. Let me know if I can help. -Dave Thanks, I'll check the versions I have. If they aren't multiprotocol versions, I contact you about the images. Regards, Kari