Re: Chat binding to *:4445 - WAS {Re: [Webct-admin] license keyed to secondary IP address of machine}

[Derek D. <di...@un...>]

On Sep 10, 2001 at 21:05 -0500, ma...@mj... wrote:
=>I realized I didn't answer the UDP/TCP question.
=>
=>The reason UDP was used was to improve performance because it
=>used to be a good idea to use UDP to improve performance in
=>applications where you didn't care if the message got there on not.
=>I'm not sure why we use both (I try not to think about the chat
=>protocol too much, it makes my head hurt :).
=>
=>But since modern tcp stacks are much better written and
=>eventually you end up reimplemnting TCP (poorly even) with UDP if
=>you maintain a UDP application long enough (because eventually
=>you do care if the messages get there and in what order), it's better
=>just to do it as TCP. Which is probably why we have TCP there as
=>well.

I am not a TCP/IP program, but I have read enough to know what Mark
mentions.  What I wonder, more out of curiouitiy, is why WeBCT chose
one port for TCP and one for UDP.  You can use one port, and still use two
different protocols.  I.e. 4445/TCP and 4445/UDP.  Using one port
number for TCP and a different one for UDP reinforces the student
written code excuse mentioned in another post.



=>On 7 Sep 01, at 18:27, Derek Diget wrote:
=>> Changing the topic here, but it is related to a multi-IP addressed
=>> machine.  We are running into an issue with our two instances of WebCT
=>> running on one box, but with apache binding to separate IP addresses.
=>> (v3.1 and 3.6 on Solaris 8)
=>>
=>> Today, I heard some people were having problems with the chat room.
=>> Open investigation, I see that WebCT's chat script has a problem.  It
=>> binds as "*:4445" by default.  This is fine on a one IP address
=>> machine, but seems to cause problems on a machine with more than one
=>> IP address.  (It sure does for the logs found under
=>> webct/generic/public/chat/log.)  I know that I can change the port
=>> numbers in each instance of WebCT, but I feel that is a hack.
=>>
=>> Before I press this issue farther, do others agree that the chat
=>> and whiteboard should look to see what address they are running under
=>> and bind accordingly?


Mark, can you answer me, (private if needed), what the stance is on
binding to *:4445.  I feal that is a bug for us running virtually
hosted machines.  I would like to see it bind to LICENSED_IP:4445.


-- 
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Derek Diget
Western Michigan University - Kalamazoo Michigan USA - www.wmich.edu/
Office of Information Technology - UNIX support - www.wmich.edu/unix/
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