Bgp

AS Number hijacking due to misconfiguration

Networking

This Sunday I was looking at global routing table dump and found AS1 announcing some very weird prefixes.

AS1 i.e Autonomous System Number 1 belongs to Level3 but as far as I know they are not actively using it. They use AS3356 globally (along with Global Crossing’s AS3549). I noticed quite a few prefixes of a Brazil based telecom provider - Netvip Telecomunicaes being announced by AS1. 

Some of entries in global routing table belonging to AS1 (as picked from BGP table dump of route-views archive):

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Private IPs in Public routing

Networking

Sometimes we see interesting IP’s in traceroute & they confuse lot of people.

I have seen this topic in discussion twice on NANOG and once on Linux Delhi user group. 

OK - let’s pick an example: 

anurag:~ anurag$ traceroute 71.89.140.11
traceroute to 71.89.140.11 (71.89.140.11), 64 hops max, 52 byte packets
1 router (10.10.0.1) 1.176 ms 0.993 ms 0.941 ms
2 117.220.160.1 (117.220.160.1) 20.626 ms 29.101 ms 19.216 ms
3 218.248.169.122 (218.248.169.122) 23.983 ms 43.850 ms 45.057 ms
4 115.114.89.21.static-mumbai.vsnl.net.in (115.114.89.21) 118.094 ms 81.447 ms 66.838 ms
5 172.31.16.193 (172.31.16.193) 115.979 ms 90.947 ms 90.491 ms
6 ix-4-2.tcore1.cxr-chennai.as6453.net (180.87.36.9) 95.778 ms 98.601 ms 98.920 ms
7 if-5-2.tcore1.svw-singapore.as6453.net (180.87.12.53) 321.174 ms
if-3-3.tcore2.cxr-chennai.as6453.net (180.87.36.6) 331.386 ms 326.671 ms
8 if-6-2.tcore2.svw-singapore.as6453.net (180.87.37.14) 317.442 ms
if-2-2.tcore2.svw-singapore.as6453.net (180.87.12.2) 334.647 ms 339.289 ms
9 if-7-2.tcore2.lvw-losangeles.as6453.net (180.87.15.26) 318.003 ms 328.334 ms 309.234 ms
10 if-2-2.tcore1.lvw-losangeles.as6453.net (66.110.59.1) 306.500 ms 326.194 ms 341.537 ms
11 66.110.59.66 (66.110.59.66) 315.431 ms 330.417 ms 308.372 ms
12 dls-bb1-link.telia.net (213.155.136.40) 354.768 ms 344.360 ms 357.050 ms
13 chi-bb1-link.telia.net (80.91.248.208) 352.479 ms 358.751 ms 359.987 ms
14 cco-ic-156108-chi-bb1.c.telia.net (213.248.89.46) 367.467 ms 370.482 ms 377.280 ms
15 bbr01aldlmi-bue-4.aldl.mi.charter.com (96.34.0.98) 387.269 ms 385.362 ms 365.694 ms
16 crr02aldlmi-bue-2.aldl.mi.charter.com (96.34.2.11) 375.275 ms 375.356 ms 371.621 ms
17 dtr02grhvmi-tge-0-1-0-0.grhv.mi.charter.com (96.34.34.83) 383.539 ms 371.817 ms 383.804 ms
18 dtr02whthmi-tge-0-1-0-0.whth.mi.charter.com (96.34.34.85) 384.400 ms 391.197 ms 393.340 ms
19 dtr02ldngmi-tge-0-1-0-0.ldng.mi.charter.com (96.34.34.87) 371.192 ms 375.679 ms 378.457 ms
20 acr01mnplmi-tge-0-0-0-3.mnpl.mi.charter.com (96.34.40.75) 364.824 ms 385.534 ms 374.401 ms
21 * *^C
anurag:~ anurag$

Let’s try pinging IP on 14th hop (which is with a major backbone Telia) - 213.248.89.46

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F-root DNS node back up in Chennai!

Dns, Networking

And finally ACN i.e “Advanced Computer Networks” exam next. Hopefully less to cram in this one and syllabus is pretty interesting. 

Talking about networks - I am very happy to post this update. Finally F root server’s node in Chennai is back up! 

Though ISC did not updated me about this development but anyways I can always assume they were busy in hitting head with India bureaucratic bodies. :)

If you are following my blog, you might have seen my past blog post about “Broken connectivity of F root server” due to NIXI’s routing policies. When I informed ISC (root server operator for F root) about it, they took down the Indian anycasting instance in order to work on fix. 

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BSNL - Softlayer connectivity problem & possible fix

Networking

It’s late night here in India. I am having final 8th semester exams and as usual really bored! 

Though this time we have interesting subjects but still syllabus is pretty boring spreading across multiple books, notes and pdf’s. Anyways I will be out of college after June which sounds good.

Tonight, I found a routing glitch. Yes a routing glitch!! :)

These issues somehow keep my life in orbit and give a good understanding on how routing works over the Internet.

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