Re: transmission probs

Jason Williams (
Fri, 6 Mar 1998 11:17:39 -0600 (CST)

On Fri, 6 Mar 1998, Fade wrote:
> I think it's probably to do with the fact that i'm running over a UNIX
> slirp connection instead of a true PPP

>From what I know and have read, CU only partially works with slirp. I
believe it won't work any White Pine reflectors due to the conference
selection box, so you might be limited to Cornell and Enhanced Reflectors
( that you mentioned is an Enhanced Reflector). My scanner
lists other Enhanced Reflectors you can try as well.

Here's a message I grabbed from Bill Neisius back in December 1996 that
may help you out:
Newsgroups: comp.dcom.videoconf
From: (Bill Neisius)
Subject: Re: CuSeeme and Slirp
Date: Wed, 4 Dec 1996 17:01:57 GMT


Blackie Lawless ( wrote:
: I have a shell account and am using Slirp. I am wondering if anyone else
: out there has been able to get CuSeeme to work under Slirp.

Well, Yes and No...

SLiRP needed a patch to work with CUSeeMe. When it detects an outbound
packet for UDP port 7648, it modifies the packet by adding the 'real'
IP address (instead of the '' it normally has). If you're
running SLiRP v1.0C, you have the patch...

The patch only sort of halfway works, and only some of the time. On the
reflectors that you can connect to (KentState and NorthCarolina for example)
you'll find that you can send and receive video, but the chat window
will be receive only... Other reflectors, especially those with multiple
conferences, will fail to connect at all...

You can sort of work around the problems though: you can enable the
chat send by re-directing UDP port 7648 _after_ you have connected to
the reflector. 'stats sockets' will then show that the port has been
re-directed twice. If you disconnect from the reflector, and attempt to
connect to another, you must kill the re-directed socket first...

Re-directing the port also seems to solve the problem of connecting to
reflectors with multiple conferences... but seems to cause other problems.
Evidently on one reflector that I connected to, I was showing two
video windows, one of which kept blinking on and off... The discussion
in the chat window wasn't very happy about the situation (!!@#!).

Safest is to _not_ redirect any ports; stick with the few reflectors
that will accept the connection; and use CUDoodle to place your chat
messages in the video window. Or download the source and see if you can
figure a better way of patching it...

One of these days I've got to get a real net connection...

Bill Neisius

--    * Jason Williams -- Austin, Tx.  |     |       * University of Texas at Austin  | ___ |         * BS Computer Science             \_|_/
*************** **************|