Re: What is the different between opening one port and a thouand ports on a firewall?

From: RT (russandsandy@no.slimey.spammers.attbi.noteven.com)
Date: 03/28/03 

From: "RT" <russandsandy@no.slimey.spammers.attbi.noteven.com>
Date: Fri, 28 Mar 2003 01:34:23 GMT

If it's a concern, check out BISP (Black Ice Server Protection). You can
tune the firewall to let all the ports you need through (or turn it off
altogether) and still have the IDS "watching" for vulnerabilities and
blocking intrusive activity.

RT

"Patrick Lam" <patrickl@astri.org> wrote in message
news:b5s2bm$1sge$1@news.hgc.com.hk...
> Dear all:
>
> I am trying to setup a VoIP system in my office so that employees from my
> company can call in/out to other their IP soft phones at home.
>
> However, this kind of deployment requires me to open up all the ports
above
> 1024 into the server with a public IP. However, not every port is
> constantly listening for incoming (UDP) traffic. What it does is that it
> only creates a UDP socket on demand, and closes it when it's done. As a
> result, although all the ports are let through (for this particular
server),
> only a few of them are actually active (being created and receiving UDP
> packets) at any moment.
>
> Is this dangerous? What can hackers do to the server or LAN under this
> situation?
>
> Actually what is the difference between opening 1 port and many port (but
no
> listening sockets behind) on a firewall?
>
> Thanks very much in advance,
>
> Patrick
>
>

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