13 Feb

Indian IPv6 deployment

I had calls with a couple of friends over this week and somehow discussion IPv6 deployment came up. “How much has been IPv6 deployment in India now in 2020” is a very interesting question. It’s often added with – “how much of my traffic will flow over IPv6 once it is enabled“?

Game of numbers

There is a drastic difference in IPv6 deployment depending on which statistic we are looking at here in India. There can be a bunch of factors based on which we can try to judge IPv6 deployment:

  1. How many operators are offering IPv6 to end users?
  2. How many end-users are on IPv6?
  3. How’s the content available on IPv6 in terms of a number of IPv6 enabled websites?
  4. How’s the content available on IPv6 in terms of traffic volume over IPv6?

First two and last two points are related and point towards from vertically opposite ends. (Call it good or bad) the fact of high centralisation. There has been an ongoing centralisation of mobile operators and in-country like ours they connect a very large number of end-users. The number of fixed-line networks has increased considerably but at the same time in proportion to a number of mobile users they user base growth has been much lower.

On the content side like everywhere else in the world, there’s a lot more centralisation of content. Many of my Indian ISP friends tell me that Google + Akamai + Microsoft + Netflix + Facebook + Cloudflare is way over 75% of their traffic. Think about it, that’s just 6 AS number out of 68000+ odd networks in the world as per BGP routing table. Thus by traffic profile, we are looking at 0.0014% networks serving 75% of content traffic. The reason for such centralisation is actually beyond network and more around the success of products of these organisations followed by factors like the winner (or top 3) gets it all in most of these domains.

For eyeball traffic APNIC IPv6 stats for India (source here) as well as Hurricane Electric’s IPv6 progress report (source here) give us some numbers:

  1. Very few fixed-line operators are offering IPv6 but on the mobile side – a large number of mobile networks are offering IPv6. Jio was on IPv6 since launch and as traffic increased, Airtel as well as Vodafone + IDEA also significantly increased their deployment. On fixed line, it’s just Jio + ACT broadband with any sizable IPv6 footprint. BSNL + Airtel have virtually no deployment. There might be some other network in the list but it’s off the radar.
  2. There are a lot more end users on IPv6 than despite the small number of networks offering it because of the large mobile user base. On Jio 80%+ user base, on Airtel, it’s 45%, on Vodafone & IDEA (merged company but still separate ASNs) it’s close to 50%. That’s the number of users who are connecting over IPv6 when given option of IPv4 and IPv6 as tested by APNIC. That number is huge!
  3. Around 98.5% of TLDs (top-level domain names like .com, .net etc) are IPv6 enabled. For .com & .net domains, only 7% of the domains have an AAAA record (compared to ones having an A record). Most of the numbers are much lower if we look at the content side of IPv6 (ignoring the traffic volume).
  4. If we look at the content players with IPv6 and include the traffic volume numbers then it’s way higher. It is estimated that globally somewhere between 20-30 top ASNs carry 90%+ traffic and almost all of those top 20 are IPv6 enabled.

What do all these numbers actually mean?

  1. If you are an eyeball network in India and you deploy IPv6, you can expect way over 70-80% traffic (by volume) on IPv6.
  2. If you are a content network/datacenter in India and application is targetting to home fixed-line / enterprise network, expect a rather low amount of IPv6 traffic but would be rapidly increasing as more fixed-line networks deploy.
  3. If you are a content network/datacenter in India and content hosted at your end attracts mobile traffic, you can expect way over 50%-60% of that mobile traffic over IPv6.

Some additional reasons to consider deploying IPv6

  1. In India, ISPs need to maintain carrier-grade NAT logs of the translations. If one is doing dual-stack, a large part of traffic will flow over IPv6 saving on those logging requirements.
  2. For ISPs, it will save you from significant strain on CGNAT device.
  3. For content network/webmaster/datacenter – IPv6 will help in delivering your traffic outside of (often) congested CGNAT paths.

Happy IPv6ing! 🙂

10 Sep

NIXI permits content players!

I am in Chiang Mai, Thailand for APNIC 48 conference. Earlier today attended APIX meeting where many IX members from Asian community gave an update including NIXI i.e National Internet Exchange of India.

As per the update NIXI now allows content players to peer at the exchange. NIXI earlier had a strict requirement of telecom license for anyone to peer but as of now it allows anyone with IP address and AS number to be part of the exchange just like all other exchanges. This is a really good development coming this year after their announcement of the removal of x-y charge. One strange thing remains that their website is still not updated to reflect that which is probably just work in progress. As per representative from NIXI they now openly welcome all content players to peer at NIXI.

What more needs to be done?

Well, a couple more changes are needed.
Here’s what I requested to the representative from NIXI:

  1. Removal of forced multi-lateral peering policy. Forced multilateral is bad idea in modern times. Many large networks (especially the ones dealing with anycast based service) would usually not like to peer at route server.
  2. So far NIXI has discouraged bilateral BGP sessions in the policy. Technically any members can create bilateral sessions but were denied in the policy. That needs to be changed. Bilateral/multilateral peering is a technical decision and should be left to individual networks operators.
  3. NIXI needs to migrate to software-based route servers like bird with auto-config generation to include features like IRR filtering, RPKI filtering, BGP communities support and much more.

Remove forced multilateral, but what about Indian incumbents?

This is an old interesting discussion. Basically due to “forced” multilateral peering policy – everyone is on route servers and that includes incumbents like Tata Communications, Airtel, BSNL and other large networks like Jio and Voda/IDEA as well. The argument there is if multi-lateral peering is not forced, local ISPs won’t be able to peer with these networks. Part of these arguments comes from a mindset which still believes the world’s traffic flows from tier 1 operators to tier 2 and tier 3. A very large part of modern internet traffic flows from content players to eyeball networks (where “eye balls” are). Content players deliver this traffic through a mix of backbone + peering as well as by putting caching nodes inside the ISPs network (like Google’s GGC, Facebook’s FNA, Netflix OCA, Akamai caching node etc). The success of an IX depends on meeting the content players and eyeball players. To connect eyeball players (which are usually spread across the region) one needs circuits i.e dark fibre, DWDM waves, or any sort of transport network. As long as these three things are in place, IX can be a success.

Look at any large IX doing over few hundred Gigabits of traffic or even terabit of traffic and ask does local incumbent telco peers openly at that IX? Does BT openly peers at LINX in London? Do Deutsche Telekom peers openly at DECIX Frankfurt? Does AT&T, Verizon, Comcast peer openly at various Equinix and Coresite exchanges spread across the US? Answer to most of these is no and that is just fine. I would personally hope that these networks do but if they do not it’s not something which blocks the development. In the same way, having Airtel/Tata/Jio/Voda-IDEA at NIXI is great and I would hope they stay but the success of NIXI does not depend on these. As long as transport circuits are available (which they are!) from enough players with competition it would be fine. As of now across India, one can take transport circuit from Airtel, Tata, Voda/IDEA, Powergrid. Railtel, Reliance Communications and more!

Forced multilateral and routing issues…

One recent issue which E2E Networks (a cloud provider based in India) faced was to send traffic to Jio. Suddenly traffic going from E2E to Jio via Tata Comm was going from outside India. As per discussions, routing was tweaked to send traffic out to Jio via Airtel and still, there were issues of routing from outside India. The issue went on for a couple of days and was eventually fixed by speaking to both ends. Issue was there due to ongoing peering issues between Jio – Tata Comm and Jio – Airtel.

Now the funny thing here is that Netmagic (which takes care of routing for E2E) connects to NIXI and Jio also connects to NIXI. During this entire time, both Netmagic (on behalf of E2E) and Jio had enough capacity at NIXI but that could not be utilised because of forced multilateral peering policy. If routes were announced to NIXI route server, that would have probably fixed the Jio issue but would also attract traffic from Airtel/Tata which was not specifically desired due to their known port capacity issues at NIXI.

Ending this post with my quote which I often give in these discussions – “Remember somewhere up the transit path there’s always peering!” 🙂


  1. This post is done in my personal capacity and nowhere reflect the views of my employer.
  2. I am on board of the mentioned organisation E2E Networks (more on it here)