ICMP Blocking Woes

Eric Kagan ekagan at axsne.com
Tue Sep 30 11:04:52 UTC 2003


> WindowsNT tracert.exe uses 92 byte icmp packets. There is a modified
version
> that uses a smaller sized icmp packet at
> http://www.nthelp.com/NT6/tracert_broken.htm that works fine on Windows
> 2000.

So if tracert1 doesn't work, would that mean Comcast is actually blocking
all ICMP ?  I have been told they are only blocking 135-139, 4444
I get the same results with tracert and tracert1 (below)

D:\Temp>ver

Microsoft Windows 2000 [Version 5.00.2195]

D:\Temp>tracert1 www.advil.com

Tracing route to www.advil.com [164.109.5.98] over a maximum of 30 hops:

  1    20 ms    10 ms    10 ms  c-24-218-168-1.ne.client2.attbi.com
[24.218.168.1]
  2    20 ms    10 ms    10 ms  24.62.0.245
  3     *        *        *     Request timed out.
  4     *        *        *     Request timed out.
  5     *        *        *     Request timed out.
  6     *        *        *     Request timed out.
  7     *        *        *     Request timed out.

D:\Temp>tracert www.advil.com

Tracing route to www.advil.com [164.109.5.98] over a maximum of 30 hops:

  1    20 ms    10 ms    10 ms  c-24-218-168-1.ne.client2.attbi.com
[24.218.168.1]
  2    10 ms    10 ms    20 ms  24.62.0.245
  3     *        *        *     Request timed out.
  4     *        *        *     Request timed out.
  5     *        *        *     Request timed out.
  6     *     ^C


Eric




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