Re: Port 8 Echo Request - Should I allow on my Firewall?

From: Lanwench [MVP - Exchange] (
Date: 10/17/03

Date: Fri, 17 Oct 2003 16:02:04 -0400

Inbound ICMP should always be blocked. Actually, *all* unneeded ports should
always be blocked.

Wayne wrote:
> Hi
> My checkpoint firewall is constantly blocking requests on
> port 8 Echo Request. The sources of these echo requests
> are numerous. However, I notice several of the source IP's
> occur in my log more than once.
> From what I've read, port 8 Echo Request is port of the
> ICMP protocol, which is part of IP. It can be used for
> good and bad purposes. It is good in such a way that a
> network admin can detect the Operating System of a unknown
> new node on the network. It is bad in such a way that a
> hacker can create a "map" of my network to prepare his DOS
> attack.
> I don't manually use ICMP to discover new nodes on my
> network.
> So, should I block incoming connections on port 8 Echo
> Request?
> Thanks
> Wayne

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