Hi Jeroen, The first thing I would say is that STAC compression must be supported on both sides of the connection. On the clients PC make sure that Enable software compression is enabled and that hardware compression is not. A rule of thumb to follow is to disable software compression when hardware compression is available which typically is over a V.42bis-compliant modem and to enable it when hardware compression is not like over an ISDN connection (which almost all support STAC). Also, Windows NT 4.0 and 2000 do not support STAC. Only PPP, MP, and MP+ links support Link-Compression. For the Lucent/Ascend units, Windows 95/98 equivalent is the MS-Stac which supports Microsoft/Stac compression. Stac-9 is the actual RFC Compression protocol. If a caller does not support MS-Stac then it will negotiate for Stac and if that is not agreed upon, they use no compression relying on the PPP. Thanks, Mario Puras JNCIS, CCNA, LSCP, MCP SoluNet Technical Support Customer Support Engineer -----Original Message----- From: Jeroen Veen [mailto:j.veen at planetmediagroup.nl] Sent: Wednesday, January 02, 2002 10:35 AM To: ascend-users at max.bungi.com Subject: (ASCEND) Stac compression leading to performance hit on maxTNT? Hi, We ran into some problems after enabling STAC compression (Datacompression for ISDN) on our TNT's. Customers were regularly complaining about sessions in which the connection is established without problems but no data comes over the line after that at all. If STAC is switched off there are (seemingly) no problems. If we switch STAC back on we start experiencing the same problems again. We think this may have something to do with the MAXTNT's not being able to process STAC for all those lines or something, but we're not sure. Any thoughts/ideas, anyone? Jeroen Veen Planet Technologies ++ Ascend Users Mailing List ++ To unsubscribe: send unsubscribe to ascend-users-request at bungi.com Archives: http://www.nexial.com/mailinglists/ ++ Ascend Users Mailing List ++ To unsubscribe: send unsubscribe to ascend-users-request at bungi.com Archives: http://www.nexial.com/mailinglists/