Date: Sat, 16 Jul 94 04:30:02 PDT From: Advanced Amateur Radio Networking Group Errors-To: TCP-Group-Errors@UCSD.Edu Reply-To: TCP-Group@UCSD.Edu Precedence: Bulk Subject: TCP-Group Digest V94 #150 To: tcp-group-digest TCP-Group Digest Sat, 16 Jul 94 Volume 94 : Issue 150 Today's Topics: DAMA DAMA v. Repeaters DAMA v Repeters Managing MSS and Window; IP encapsulation Send Replies or notes for publication to: . Subscription requests to . Problems you can't solve otherwise to brian@ucsd.edu. Archives of past issues of the TCP-Group Digest are available (by FTP only) from UCSD.Edu in directory "mailarchives". We trust that readers are intelligent enough to realize that all text herein consists of personal comments and does not represent the official policies or positions of any party. Your mileage may vary. So there. ---------------------------------------------------------------------- Date: Fri, 15 Jul 94 09:02:34 From: kz1f@RELAY.HDN.LEGENT.COM Subject: DAMA To: tcp-group@UCSD.EDU Pardon my total ignorance here but what exactly is DAMA. I have a similar question of bit-regen. I, too, though it was referring to a hardware repeater, ala ethernet, but there is a difference. Actually what I thought was a uWave repeater where 2 gunnplexers where attached back to back, input A going to output B and visa versa. This I imagine would work since the uWave is highly directional. But where I have problems is in a 2mtr environment where the out of B can not be on the input of A. Or are you referring to a full duplex, open squelch digital repeater similar to what Charlie, W1CG set up in RI? Walt ------------------------------ Date: Fri, 15 Jul 1994 09:44:40 -0500 (CDT) From: ssampson@sabea-oc.af.mil (Steve Sampson) Subject: DAMA v. Repeaters To: tcp-group@UCSD.EDU nelson@crynwr.com (Russell Nelson) writes: > Also, why should the hub be doing any transmitting? It should just > assign slot times for the users, assigning more slots to more active > users. Demand Assigned Multiple Access (DAMA) was written up in the 8th ARRL CNC of 1989 (p 203). I don't know if the protocol has even been specified or is just being experimented with in Germany. The object was to modify slightly the AX.25 protocol rather than invent a new one. This modification was a solution for the hidden terminal problem using half-duplex. To answer your question, I guess it was a design decision. They just used polling to regulate the users transmitter. "As long as no information transfer occurs between user and node, (idles) then the node sends its polls as an RR with the corresponding count. If the response by the user is just an RR#, then the time until the next poll to this user will be lengthened to avoid unneccessary channel load. The exact amount of time added is determined by total channel activity" (205). -- Steve ------------------------------ Date: Fri, 15 Jul 94 15:49:53 EST From: BARRY TITMARSH Subject: DAMA v Repeters To: TCP-GROUP Not that i like to say this but in the location that i live at this time where tcpip is not at all liked on the digis, I can see the use of the DAMA mode to cut out the use of mode TCPIP unless the mode DAMA is implemented to NOS, Currently the only version of NOS that has dama SLAVE mode built in is WNOS-5 and some patched versions of WNOS-4A?x Flexnet is fast being implemented with DAMA Master mode. thus forceing users to go get firmware that has DAMA Slave mode.. If you dont then TUFF you just dont get a UA to your SABM any more.. I agree that DAMA is usefull for the HTP and to make a busy channel more useable by controlling the use of the ether, For the digis in my Location I welcome the use of DAMA Master mode on the node and the users to use DAMA Slave, But not as a means to shut the door on the much disliked TCPIP traffic on the digis at the Expence of the TCPIP user. Ok.. Barry GM8SAU / DC0HK ------------------------------ Date: Fri, 15 Jul 94 09:28:44 EDT From: "Barry Siegfried [198.6.114.100]" Subject: Managing MSS and Window; IP encapsulation To: tcp-group@UCSD.EDU Hi, all... Brian Lantz wrote: > TNOS, based on an earlier version of JNOS, only checks for receiving 94. > It's funny that this came up today, since I was looking at a couple of > different IPIP listings (including xNOS) to see what differences there > were, since I'm looking into figuring out the patches needed to do it > under Linux. > > Phil's is the only one I KNOW about that checks also for a '4'. As of a few days ago, MFNOS (also based on an earlier version of JNOS) now checks for both 4 and 94 PIDS on the receive side of the IP-IP encapsulation code. It still transmits a 94 PID, however. Barry +-------------------+ | Barry Siegfried | | bgs@intac.com | +-------------------+ ------------------------------ End of TCP-Group Digest V94 #150 ******************************