NIXI

Just finished with SANOG 26 conference and tutorials. It went very nice. Interestingly this time conference did not start early morning like it did in SANOG 24 at Noida. It was rather late in afternoon. Also, on very good note - there were less Govt. bureaucrats to bore attendees with usual stuff they always talk about but have very little idea. One specific interesting presentation was  Opportunities and Challenges for Broadband Wireless in India by Prof Abhay Karandikar (from IIT Mumbai). In start I felt it to be usual crappy 5G talk but later realized it was much more interesting. I loved the idea “Have 2Mbps everywhere static broadband and not some absurd number on mobile wireless broadband as we hear in case of 3G/4G. Although 2Mbps now is much slower and I would rather suggest that we target for 10Mbps everywhere (something which can be supported by copper/coax/fiber hybrid) but anyways it was nice refreshing talk. His thoughts were interesting but mostly impractical since had high dependence on useless project like NOFN. For the next part, we had a nice theme of keeping network simple which everyone kind of liked. Simplicity in Network Design & Deployments by Dany Pinto (from Colt) and Unified Forwarding with Segment Routing by Mohan Nanduri (from Microsoft Azure Cloud WAN team) were part of that. Santanu Dasgupta gave a presentation about Challenges of L2NID based Metro-E Architecture for vCPE/NFV Deployments and kind of confused everyone. :P

And my post on 1st April. Don’t take it as April fool post ;)

Multiple times NIXI’s AS24029 has been reported as acting like transit ASN for multiple networks. I have analysed it in past and this is very much because of route leaks by few specific networks. I have explained difference in peering Vs transit routes and their handling previously on my blog.

In short: A network is supposed to re-announce it’s peering and transit routes only to customer and not to any other peer or upstream. Whenever NIXI’s ASN appears in global routing table, its always the case where one or more networks are re-announcing routes learnt via NIXI to their upstream transits. 

Earlier this month Dyn started with it’s Indian PoP. I came across news from Dyn’s blog post. It’s very good to see first Amazon AWS and now Dyn in India. With a warm welcome to Dyn let’s look at their Indian deployment.

Dyn using AS33517 which seems to be having upstream from Tata-VSNL AS4755 and Airtel AS9498. 

Dyn seems to be announcing 103.11.203.0/24 to both networks in Mumbai to transit. There are routes in global IPv4 routing table which show Tata & Airtel as transit for Dyn. It cannot be just a /24. I am sure there are more prefixes which are very likely locally announced. Since deployment is at Mumbai, let’s try to look at NIXI Mumbai for prefixes.We can see Tata AS4755 is using 218.100.48.85 and Airtel is using 218.100.48.86 from NIXI route server at Mumbai with simple “sh ip bgp sum” query. I tried taking entire table of Tata as well as of Airtel from NIXI route server but not able to get it beyond few thousand routes. 

Few days back I noticed F root server (which is with ISC) brought it’s anycasted node in NIXI Chennai back live. They have taken that down as per my interaction with them over mailing list. My last post about F root coming back live was with guess work on who’s providing upstream.   Today I spent sometime in finding who’s providing transit to that node. It is very important to note that most of these key infrastructure related nodes rely on peering for most of traffic but a transit in form of full table or default stays so that one can push packets to a route if it is not in table learnt from peering. In case of Indian deployment which was at NIXI Chennai - many ISPs were following regional routes clause of NIXI and were announcing just their regional routes (to ISC’s F root router) but quite a few of them (like BSNL) were still learning routes from one region and exporting them into their other region via their IGP. This brought case where my router (sitting on BSNL link) was getting a forward path to NIXI Chennai for F root but there was return path from F root to my system because BSNL wasn’t announcing Northern prefixes in Chennai based NIXI. As I noted earlier F root is back live in India and I am getting consistant and direct routes. It seems very much the case of addition of transit on that node. Today I was looking at global table dump and I came across some interesting routes which revealed who is probably the transit for ISC’s F root in India. :)

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.