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And college started after pretty good holi holidays. Again having bit painful time due to hot weather and this is just start of summers. Well all I can hope is that there won’t be voltage issues in village again (like last time). And just to make sure on that part - I have put 2 RTI’s asking Power department about their preparation details. :)

Anyways coming on blog post topic for the day - the effect of “next-hop-self” at an IXP when there are peers as well as transit customers of a network. Just to be clear in start - this post will stick to technical side of it and without going into IXP policy side of it.

Fest time at college - Good since I get lot of free time to spend around looking at routing tables. It’s always interesting since last week was full of some major submarine cable cuts and has huge impact on Indian networks.

Anyways, an interesting issue to post today about Global IPv6 routing . There are “dark spots” in global IPv6 routing because of peering dispute between multiple tier 1 ISPs involving Hurricane Electric (AS6939) & Cogent Communications (AS174).  What’s happening here is that both tier 1 providers failed to reach on agreement to keep peering up in case of IPv6. This has resulted in parts of global IPv6 internet where packets from one network (and it’s downstream) can’t reach other network or their downsteam singled hommed networks. 

Today a friend from Pakistan informed about SMW4 outage. He reported about issues in Pakistan.

It seems like SMW4 is damaged near Egypt and that is what causing high load on East Asian routes giving pretty high latency.

I am at my home and sitting BSNL’s network and latency with Europe has jumped terribly to 700-800ms. Right now I do not see a direct route to Europe and it’s rather taking East Asia > US > Europe routes right now on other cable networks.

Just was looking at routing tables of BSNL. They have a significant address space in /10 - 117.192.0.0/10. Overall this /10 address space is divided into /18 and /20 subnets.

Let’s pick two of such subnets and observe routing tables from route-views:

1. 117.192.0.0/18
2. 117.192.0.0/20 

Routing table for 117.192.0.0/18: 

* 117.192.0.0/18 193.0.0.56 0 3333 3356 6453 4755 9829 9829 9829 i  
* 194.85.102.33 0 3277 3216 6453 4755 9829 9829 9829 i  
* 194.85.40.15 0 3267 174 6453 4755 9829 9829 9829 i  
* 129.250.0.11 6 0 2914 6453 6453 4755 9829 9829 9829 i  
* 128.223.253.10 0 3582 3701 3356 6453 4755 9829 9829 9829 i  
* 4.69.184.193 0 0 3356 6453 4755 9829 9829 9829 i  
* 209.124.176.223 0 101 101 3356 6453 4755 9829 9829 9829 i  
* 69.31.111.244 3 0 4436 2914 6453 6453 4755 9829 9829 9829 i  
* 207.46.32.34 0 8075 6453 4755 9829 9829 9829 i  
* 66.59.190.221 0 6539 6453 4755 9829 9829 9829 i  
* 12.0.1.63 0 7018 6453 4755 9829 9829 9829 i  
* 208.74.64.40 0 19214 2828 6453 4755 9829 9829 9829 i  
* 203.181.248.168 0 7660 2516 6453 4755 9829 9829 9829 i  
* 66.185.128.48 111 0 1668 6453 4755 9829 9829 9829 i  
* 134.222.87.1 0 286 6453 4755 9829 9829 9829 i  
* 157.130.10.233 0 701 6453 4755 9829 9829 9829 i  
* 114.31.199.1 0 0 4826 6939 1299 6453 4755 9829 9829 9829 i  
* 89.149.178.10 10 0 3257 6453 4755 9829 9829 9829 i  
* 154.11.98.225 0 0 852 3561 6453 4755 9829 9829 9829 i  
* 202.249.2.86 0 7500 2497 6453 4755 9829 9829 9829 i  
* 154.11.11.113 0 0 852 3561 6453 4755 9829 9829 9829 i  
* 144.228.241.130 0 1239 6453 4755 9829 9829 9829 i  
* 217.75.96.60 0 0 16150 1299 6453 4755 9829 9829 9829 i  
* 207.172.6.20 0 0 6079 3356 6453 4755 9829 9829 9829 i  
* 206.24.210.102 0 3561 6453 4755 9829 9829 9829 i  
* 195.66.232.239 0 5459 6453 4755 9829 9829 9829 i  
* 208.51.134.254 2523 0 3549 6453 4755 9829 9829 9829 i  
* 207.172.6.1 0 0 6079 3356 6453 4755 9829 9829 9829 i  
* 216.218.252.164 0 6939 1299 6453 4755 9829 9829 9829 i  
* 203.62.252.186 0 1221 4637 6453 4755 9829 9829 9829 i  
*> 66.110.0.86 0 6453 4755 9829 9829 9829 i  
* 164.128.32.11 0 3303 6453 4755 9829 9829 9829 i  
* 202.232.0.2 0 2497 6453 4755 9829 9829 9829 i

Routing table for 117.192.0.0/20:

Finally back in village location.

Was just looking around and saw BSNL having really crazy routing. I looked around and saw this:

NIXI Looking Glass - show ip bgp neighbors 218.100.48.15 routes

Router: NIXI Delhi (Noida)

Command: show ip bgp neighbors 218.100.48.15 routes

Total number of prefixes 0

Clearly BSNL is NOT announcing any prefix at NIXI Delhi at all. Thus if one has to send packets to BSNL in North area either it will be via transit (Tata/VSNL) or via any other peering NIXI exchange in Mumbai or Chennai.