My upstream provider must be blocking this traffic...I can't ping or trace
anything off my network.

Choice one in NY

Andy

----- Original Message -----
From: "R. Scott Perry" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Friday, August 29, 2003 3:49 PM
Subject: RE: [IMail Forum] OT NEWS FLASH: Adelphia views Pings as illegal


>
> >I specifically blocked ICMP type 8 which is the echo request, all other
> >ICMP packets flow, and I tested from a Win XP box both tracert (win
> >version) and ping, received the desired results (worked fine and
> >destination unreachable respectively).
>
> It sounds like ICMP type 8 isn't being dropped.
>
> tracert (Windows version) uses ICMP type 8 (same as ping); the difference
> is that tracert varies the TTL of each packet (so they come back before
> they reach the destination.
>
> For ping, if the packet is dropped, you should see "Request timed
> out".  The "Destination unreachable" means that the ICMP type 8 packet
went
> out, and a "Destination unreachable" packet came back, indicating that the
> packets aren't being dropped.
>
> >Using MTR (Matt's Traceroute) from a NetBSD box on my network packet loss
> >within the LAN went from
> >65-75% to 6%.
>
> That is very strange.  I can't explain why that would happen, unless ICMP
> type 8 was being dropped, but it doesn't seem to be.
>
> >   MTR uses traceroute to determine the path, then pings
> >each hop in succession to get statistics for each hop.  Interesting that
> >ping and traceroute are implemented with different protocols, I thought
> >they only used different ICMP packet types.
>
> Ping and tracert (Windows version) both use ICMP type 8 packets (ping
sends
> a packet with a high TTL so it will reach the destination; tracert sends
> increasing TTLs with each packet to see where each hop is).  Traceroute
> (Unix version) uses UDP packets (typically on ports over 30,000).
>
>                                                     -Scott
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