Re: Getting through firewalls using HttpWebRequest

From: Dale (daleDeletepres_at_msndotcomNot.Net)
Date: 07/21/04 

Date: Tue, 20 Jul 2004 20:46:24 -0500

Generally, if the request is initiated by the client, then the response can
made on any port and the firewall will allow it. The firewall should
associate the return data with the request and allow the packet. What is it
that makes you come to this conclusion?

Dale

"Bruce Wolfe" <bwolfe@cgate.net> wrote in message
news:87899f0e.0407200650.7cf93a9e@posting.google.com...
> We are having a problem with firewalls. We can't pinpoint the exact
> problem but the working theory at this point is the request from the
> client software is reaching the server through port 80. The response
> from the server is not making it back because the return port back to
> the client software being blocked by the firewall. This seems to be an
> intermittent problem because some of the ports are open through the
> firewall and some are not. Outbound from the client to the server
> (port 80) is obviously not blocked. The firewall and the settings are
> at the client site and out of our control. First question: Is this a
> good theory? 2nd: What is a good , general strategy for dealing with
> these issues? 3rd: Can we control the inbound port - one that is not
> blocked? 4th: Can we use a persistent connection so the inbound port
> will not change? Would the inbound port change anyway even of we had a
> persistent connection?
>
> Thanks. Any help with this would be greatly appreciated.

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