K root in Noida seems to be not getting enough traffic from quite sometime and connectivity does seems bit broken. This is a blog post following up to Dyn’s excellent and detailed post about how TIC leaked the world famous 193.0.14.0/24 address space used by AS25152. It was good to read this post from RIPE NCC written by my friend Emile (and thanks to him for crediting me to signal about traffic hitting outside!)
A blog post dedicated to BSNL AS9829. It just tried so hard to become as irrelevant as it can from everyone’s life (and that doesn’t excludes me now). So what really is BSNL btw?
All above tells nothing but ways in which BSNL is 100% screwed up for now. I don’t expect it to ever pick up again. Politically, technically, and fundamentally it’s a mess. I became BSNL broadband user in 2008 and it has been over 7 years of (painful and terrible) experience with them. As a company which put so much of infrastructure to connect India worked extremely hard to do as many stupid things as possible. For me trouble remained that in my city they were only wired telecom provider for retail services. Last month I got a long haul circuit from Airtel (provisioned on fiber) between my city and a friend’s ISP PoP for 10Mbps bandwidth. Circuit is delivered at a Airtel BTS site location (slightly away from my home) and I have installed Microtik SXT Lite 5’s shooting link from there to my home (around 1km link with clear LoS). This is a usual long range fixed wireless RF link over un-licensed 5.8Ghz band. (Thankyou govt. of India for delicensing it in 2007 and making available for public use). Thanks to companies like Microtik and Ubiquiti for opening up world of good fixed wireless radios and antennas which really work great and are available for quite good prices. I got pair of SXT Lite5’s from Amazon.in at 7700 INR (~$116). Fortunately BTS site has a private WISP tower and the owner of tower agreed to let me use his tower for my radio for reasonable price.
Yesterday I was driving and radio was pretty boring. Next, I connected cell phone to car’s stereo (I use a PT-750 to wirelessly connected my devices to car’s audio system). Next I tuned into Gaana.com app and experience was overall good. The way whole setup was working itself is a wonder - wireless profiles keeping layer 3 link (IP address of device) consistent and handovers happening on layer 1. On top of that a while world of backbone routing across AS9498 backbone the hosting provider’s network of the app. Now an interesting thing in this setup was the IP allocations. I that IP allocated by Airtel was 100.92.215.253.
I thought about this long back - “Who pays to whom in case of internet bandwidth?” I have been working in this domain from sometime and so far I have learnt that it’s really complex. I will try to put a series of blog post to give some thoughts on this subject. Firstly we have to understand that when we talk about “bandwidth price” it’s often layer 3 bandwidth which you buy in form of capacity over ethernet GigE, Ten-GigE and so on (or STMs if you are in India). As we know from back school class in networking - layer 3 works over layer 2 and so to deliver “bandwidth” on layer 3, one needs layer 2 physical circuit. Price paid by companies on layer 2 Vs layer 3 varies significantly based on their location, type of business, their target goal etc. E.g a content heavy company like Google pays hell lot of money on layer 2 circuits while it is strongly believed among networking community that Google is a tier 1 network and hence a “transit free” zone and they do not pay any amount on layer 3. In general the trend is pretty much as big networks have larger network footprint and connected “PoPs” over layer 2 (leading to a higher layer 2 bill) while relatively lower layer 3 bill while small networks depend significantly just on transit bandwidth (in form of layer3) and have very low layer 2 footprint.
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.
And finally academic session over. Done with all vivas and related stuff. Next will be exams likely in June. Time for me to get ready for travel. :) Anyways an interesting topic for today’s post - Google Public DNS. Lot of us are familier with popular (and free) DNS resolvers 8.8.8.8 and 8.8.4.4. I have covered reason in previous posts on why it tends to fail with Content Delivery networks like Akamai which rely on anycasting at bottom DNS layer and simple unicasting on application servers. Anycasted DNS nodes point to application servers based on various factors like distance, load, cost etc out of interesting algorithms these CDN networks use for load & cost management. Anyways today’s post focus is not CDN issues with these resolvers but Google Public DNS itself. Are these servers located in India and everywhere else where Google has PoPs? Let’s do a simple trace to get forward path from Airtel to Google’s 8.8.8.8:
Back in India after amazing APRICOT 2013 at Singapore. It was nice to stay in East Asia for a while and look around. :)
Anyways, issue for today - I have been using Airtel DNS servers from quite sometime since BSNL has crappy DNS while Google gives issues with Akamai while OpenDNS doesn’t has any node in India yet.
Today I noticed a NXDOMAIN redirection for a non-working domain and later investigated. It seems like Airtel is hijacking on NXDOMAIN queries now.
Yesterday I had a discussion with a friend from Airtel after long time. For some strange reason discussion topic was changed to old statements from Bharti Airtel’s executives that companies like Google, Facebook, Yahoo etc should pay to ISPs like Airtel for “data interconnection”. The argument goes more for Google then any other company. Statements from Airtel can be found here and here.
Companies like Airtel who have built a “physical infrastructure” feel that companies like Google should pay to them since they are putting so much of traffic on their networks. Airtel feels that services like YouTube take significant amount of bandwidth and thus requires and infrastructure from core, middle mile to edge part of network and all that needs significant investment. Similarly there was another argument from Mr Sunil Mittal about fact that Facebook is enjoying on top of infrastructure which ISPs like Airtel have created.
This is a very popular mistake admins make - it’s missing . i.e dot in the end of hostname. This causes serious problems (and lot of frustration!).
E.g taking example of popular Google’s cname record ghs.google.com. As we know if one would like to use mail.domain.com., he has to point the CNAME record to “ghs.google.com”. Now here if one misses dot in the end of ghs.google.com. - it will give a real value like:
Today I read in news about Govt’s decision to finally end inter-circle roaming agreements between Airtel, Vodafone & IDEA. Well, the case is not new. It has been up with doT from over months and got highlights when CEO’s of all 3 firms wrote letter to Prime Minister of India for his intervention.
In 3G auction held in 2010, none of the operators got pan India spectrum across 22 telecom circles. Most of them have license in around 10 circles (few in 9, few in 11 and so on) and thus no one can provide full Nationwide 3G coverage.