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@gmail.com To: AMPRNet working group 44net@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