Title: SNA vs IPX interpretation
Hi,
I work for Texas Instruments and we have a our own SNA 3270 Controller software that we wrote and supported since the 1980's. We are currently converting this software from Token Ring / 3745 interface to Ethernet / LLC / Cisco SNASW. Each instance of the software on a particular box can support up to 8 logical PU's. We are currently using Linux as the software platform.
We are using Ethereal to trace the LLC / SNA traffic. SNA LLC requires we use SAP addresses that are modulo 4, i.e. 0x04, 08, 0C, 10, 14, 18, 1C and 20 when we emulate 8 PU's. Ethereal interprets all packets with a DSAP's greater than or equal to 0x10 as IPX protocol instead of SNA. Is there anyway to get Ethereal to interpret the DSAP's of 0x10 through 0x20 SAP's as SNA? One thought is to for Ethereal to interpret the packet as SNA if either the DSAP or SSAP is < 0x10, since the SNA server side is always 0x08.
Regards,
Jim Harrison