Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!caip!clyde!cbatt!cbosgd!ucbvax!BRL.ARPA!klem From: klem@BRL.ARPA Newsgroups: mod.protocols.tcp-ip Subject: (none) Message-ID: <8609061149.AA03290@ucbvax.Berkeley.EDU> Date: Fri, 5-Sep-86 16:03:59 EDT Article-I.D.: ucbvax.8609061149.AA03290 Posted: Fri Sep 5 16:03:59 1986 Date-Received: Sat, 6-Sep-86 20:35:55 EDT Sender: daemon@ucbvax.BERKELEY.EDU Organization: The ARPA Internet Lines: 42 Approved: tcp-ip@sri-nic.arpa Subject: imprecise DDN X.25 specification? Newsgroups: mod.protocols.tcp-ip Distribution: usa To: tcp-ip@sri-nic.arpa Keywords: DDN X.25 CDC We have a contract with CDC to build and install an interface from a CDC Cyber 750 running NOS to a MILNET IMP. The contractors attended a 3-day TCP/IP Vendor Workshop in Monterey last month. They came away from the meeting with lots of questions. Can anyone answer the concerns that were surfaced at the meeting (see below for the contractor's questions)? ------------------------------------------------------------------------- It was stated that the contractor can be implementing X.25 in agreement with the contract specification, pass the DCA Qualification Test and not be able to communicate with the IMP. This is a result of the imprecise DDN X.25 specification and the incompleteness of the X.25 Qualification Testing. One X.25 issue that was discussed was the X.25/1822 incompatibility on the network. It is our understanding that the government has developed hardware and software solutions and has the situation under control. Other issues that could affect the CDC interface to the IMP include: 1) CDC X.25 does not establish a virtual circuit for each and every local network destination host and corresponding precedence. 2) CDC will provide the destination address to the IMP through the IP header, as opposed to the X.25 header. 3) CDC will not map an IP address into X.25 and vice-versa. Is it true that any or all of the above issues will create problems in the CDC interface with the DDN? --------------------------------------------------------------------------- Thanks, George Klem