Re: About ping request?

From: Patrick Morris (pmorris@wilshire.com)
Date: 05/20/02 

Date: Mon, 20 May 2002 11:02:53 -0700
From: Patrick Morris <pmorris@wilshire.com>
To: focus-ms@securityfocus.com

Blocking all ICMP from outside to inside would allow pings out, but the
replies to them would be blocked on the way back in.

To make this work, one would have to allow ICMP echo-request traffic to
leave the network, and allow ICMP echo-reply traffic to enter.

On Sun, 19 May 2002, Andrew Bailey wrote:

> Create a Packet filter rule on your firewall allowing ICMP
> from internal network to extenal network.
>
> Create a second Packet Filter rule on your firewall
> denying ICMP from the external network to internal network.

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