[169] in linux-net channel archive
Re: PPP and VJ compression problem
daemon@ATHENA.MIT.EDU (Stephen Davies)
Thu Mar 30 05:37:51 1995
From: "Stephen Davies" <scldad@sdc.com.au>
To: Al Longyear <longyear@netcom.com>
Cc: Stephen Davies <scldad@sdc.com.au>, linux-ppp@vger.rutgers.edu,
linux-net@vger.rutgers.edu
Date: Thu, 30 Mar 95 18:33:20 +0930
In-Reply-To: Your message of Tue, 28 Mar 1995 18:58:27 -0800 (PST).<199503290258.SAA00153@longyear.slip.netcom.com>
Thanks Al.
I tried vj-max-slots at 8, 4 and 2 without any success. (It will not
accept 1)
Is it worth trying any other values?
Stephen.
>Stephen Davies wrote:
>
>> The only way I can get non-trivial transfers to work is to turn off VJ
>> compression. That is:
>>
>> pppd /dev/cua1 38400 -vj asyncmap 00000000 crtscts lock defaultroute
connect
>> 'chat -v -f /etc/pppscript'
>>
>> works perfectly but if I remove the -vj, I get disconected after
>> transferring
>> a couple of K bytes.
>
>How about after a couple of frames for a connection? Say, 16 . . . :)
>
>> Mar 27 18:12:52 mustang chat[233]: Cisco Systems - Customer
>> Information
>
>> Mar 27 18:13:17 mustang pppd[232]: sent [IPCP ConfReq id=0x1 <addr 203.2.
199.1>
>> <compress VJ 0f 01>]
>> Mar 27 18:13:17 mustang pppd[232]: rcvd [IPCP ConfReq id=0x1 <compress VJ
0f
>> 00> <addr 192.189.54.157>]>
>
>Here is the request from the remote asking if it is legal to use VJ
>header compression with 16 slots.
>
>> Mar 27 18:13:17 mustang pppd[232]: sent [IPCP ConfAck id=0x1 <compress VJ
0f
>> 00> <addr 192.189.54.157>]
>
>The answer from Linux is yes.
>
>> Mar 27 18:13:17 mustang pppd[232]: rcvd [IPCP ConfAck id=0x1 <addr 203.2.
199.1>
>> <compress VJ 0f 01>]
>
>Here is the acknowledgement that the system will accept 16 slots.
>
>
>Stephen,
>
>There are some terminal servers which will do nasty things such as
>'lie'. They will say that they will accept VJ header compression with
>16 slots as indicated by the trace above. Unfortunately, they really
>don't expect clients to use that many slots.
>
>You should try the option "vj-max-slots 1" and see if this will work
>rather than disabling the VJ header compression all together. If this
>does work, try it with two, then three. You may have to work up to 16,
>which is the default value.
>
>Possible problems have been noted for the Annex (Xylogics) terminal
>server with their 5.2 revision code.
>
>In addition, the 'dp' program with revision 3.1.2 had problems for
>other reasons, but along the same lines.
>
>--
>Al Longyear longyear@netcom.com
========================================================================
Stephen Davies Consulting scldad@sdc.com.au
Adelaide, South Australia. Voice: 61-8-2728863
Computing & Network solutions. Fax : 61-8-2741015
