Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!gem.mps.ohio-state.edu!rpi!image.soe.clarkson.edu!news From: nelson@sun.soe.clarkson.edu (Russ Nelson) Newsgroups: comp.dcom.lans Subject: Re: PC/IP and the Packet Driver. Message-ID: Date: 14 Oct 89 05:04:47 GMT References: <489@excelan.COM> <6635@pdn.paradyne.com> <736@ftp.COM> <6646@pdn.paradyne.com> <738@ftp.COM> Sender: news@sun.soe.clarkson.edu Reply-To: nelson@clutx.clarkson.edu Organization: Clarkson University, Potsdam NY Lines: 26 In-reply-to: jbvb@ftp.COM's message of 13 Oct 89 14:43:21 GMT In article <738@ftp.COM> jbvb@ftp.COM (James Van Bokkelen) writes: In article <6646@pdn.paradyne.com>, dixon@gumby.paradyne.com (0000-Tom Dixon(0000)) writes: > A couple of questions: > We have never tried this but have always wondered it. Can you use > the packet driver with multiple TCP/IP applications? Say for example > NCSA Telnet and PC-NFS. Or would the packet driver get really confused? In the basic packet driver, the packet demultiplexing is done at the link layer; by Ethertype in Class 1, or 802.2 header in Class 11. Thus, there can be only one stack getting IP packets (Ethertype 0x800) or XNS packets (Ethertype 0x600) at any given time. The second IP stack should get an error on the access_type() call. Some people at Clarkson hacked a special driver to do demuxing at higher levels, but they may not be using it anymore. Right, we're not using it anymore. We did it so that we could run RVD and NCSA Telnet at the same time. It worked, but it was kind of gross. My own opinion is that protocol stacks are too bulky to have two sets of code doing the same thing (TCP or IP). I agree. -- --russ (nelson@clutx [.bitnet | .clarkson.edu]) Live up to the light thou hast, and more will be granted thee. A recession now appears more than 2 years away -- John D. Mathon, 4 Oct 1989.