12 Jul
2019
12 Jul
'19
4:50 a.m.
On Fri, Jul 12, 2019 at 02:27:15AM -0700, Nate Sales via 44Net wrote:
Date: Fri, 12 Jul 2019 02:27:15 -0700
From: Nate Sales <nate.wsales(a)gmail.com>
To: AMPRNet working group <44net(a)mailman.ampr.org>
Subject: Comcast Xfinity Routing
Hello,
I'm wondering if anyone here has had success with an IPIP gateway on
Xfinity by Comcast. I haven't had a lot of success with it, and I'm
wondering if even in "bridge" mode the CPE modem/router that they give you
is still blocking protocol 4.
73,
KJ7DMC
Nate:
Whatever your current modem configuration is, it's blocking protocol 4 (IPIP).
Specifically, a traceroute to your gateway, 157.230.161.245 using ordinary
UDP traceroute succeeds. Doing the same thing with protocol 4 (IPIP) gets
a "Protocol Unreachable" ICMP return from your gateway. Viz:
# traceroute -n 157.230.161.245
traceroute to 157.230.161.245 (157.230.161.245), 64 hops max, 40 byte packets
1 169.228.34.82 0.575 ms 0.569 ms 0.561 ms
2 132.239.255.49 0.223 ms 0.206 ms 0.200 ms
3 132.239.254.162 0.247 ms 0.536 ms 0.235 ms
4 132.239.254.149 0.356 ms 0.393 ms 0.265 ms
5 137.164.23.57 2.871 ms 2.841 ms 2.740 ms
6 137.164.22.46 5.335 ms
137.164.11.2 5.129 ms
137.164.22.46 5.165 ms
7 4.35.156.65 4.972 ms 4.911 ms 4.968 ms
8 * * *
9 4.14.33.70 12.617 ms 19.749 ms
4.14.33.54 14.277 ms
10 * * *
11 * * *
12 157.230.161.245 13.960 ms 12.958 ms 14.074 ms
...and...
# traceroute -n -P 4 157.230.161.245
traceroute to 157.230.161.245 (157.230.161.245), 64 hops max, 40 byte packets
1 169.228.34.82 0.613 ms 0.611 ms 0.577 ms
2 132.239.255.49 0.218 ms 0.197 ms 0.215 ms
3 132.239.254.162 0.363 ms 0.227 ms 0.224 ms
4 132.239.254.149 0.364 ms 0.258 ms 0.263 ms
5 137.164.23.57 3.111 ms 3.025 ms 3.108 ms
6 137.164.11.2 5.091 ms 5.122 ms 5.094 ms
7 4.35.156.65 5.219 ms 4.967 ms 4.974 ms
8 * * *
9 4.14.33.70 13.814 ms 13.901 ms 13.844 ms
10 * * *
11 * * *
12 157.230.161.245 14.829 ms !P 14.102 ms !P 13.926 ms !P
- Brian