Bharti Airtel starts peering in Russia
While reviewing the weekly changes in PeeringDB for some interesting ASNs, I noticed that Airtel AS9498 has added a few locations since my script last checked (one week ago!). Most of the other locations and upgrades seem routine, but one interesting addition is MSK-IX Moscow. According to PeeringDB record of Airtel, they now have a 100G port at MSK-IX Moscow. I won’t delve into the geopolitics here, as that’s not my area. Instead, I’m more interested in the BGP routing aspects.
While PeeringDB and the MSX-IX website list Airtel as an active member, the question is—are they actually routing anything through this link? How is Airtel possibly reaching Russia from India? Is it the usual route via Europe, or could it be through the Middle East? Is Airtel present there solely for peering, or are they have IP transit downstreams?
To get answers to these questions, we need to look into the routing table. As I’ve mentioned in previous posts, the routing table shows what’s visible, but there may be additional details that aren’t immediately apparent. Often it’s easier to find transit relations than to find peering relations.
Routing analysis
MSK-IX runs a public-facing looking glass. A quick BGP summary command shows Airtel’s session which is up since 17th Oct 2024 and is announcing 23,226 IPv4 prefixes. That covers a large part of Airtel’s own and downstream routes. Their total announcement is around 26,225 as I type this post.
A glance at this list reveals 69 routes with ‘9498 714’ (AS714 is Apple). Likely just the usual case AS714 has some Indian IPs routed behind Airtel. I don’t think Apple would be serving traffic to Russia from India as they can likely still do that from the EU more efficiently.
Let’s trace from over 400 RIPE Atlas probes in Russia towards one of the IPs from this - 17.1.108.1. I expect traffic to land in India regardless of whether it is going via this peering or not because the announcement seems to be only via Airtel AS9498 and Tata Comm AS4755 - https://bgp.he.net/net/17.1.108.0/24#_graph
The question here is - do a lot of them land in India via MSK-IX handover?
Most of the traces seem to be timing out in the middle but this gives some hints:
Traceroute for Probe 1006351
Hop IP Address Reverse DNS ASN RTT 1 RTT 2 RTT 3
1 185.14.46.2 210756 10.879 ms 0.528 ms 0.423 ms
2 92.223.64.3 210756 0.54 ms 0.483 ms 0.451 ms
3 10.255.27.185 0.545 ms 0.558 ms 0.527 ms
4 * * * * * *
5 * * * * * *
6 80.81.194.250 dx1.in.airtel.com 50.629 ms 45.448 ms 45.419 ms
7 182.79.224.25 9498 156.516 ms 142.817 ms 142.69 ms
8 125.21.13.70 9498 143.846 ms 143.851 ms 143.783 ms
9 17.0.17.112 714 168.704 ms 168.735 ms 168.697 ms
10 17.0.16.184 714 168.858 ms 168.862 ms 168.804 ms
11 17.0.16.185 714 166.949 ms 168.305 ms 166.797 ms
12 17.1.108.1 714 170.381 ms 170.356 ms 170.324 ms
Hop 6 shows Airtel in Dubai with a latency of 50ms.
This trace shows clear routing via MSK-IX:
Traceroute for Probe 7140
Hop IP Address Reverse DNS ASN RTT 1 RTT 2 RTT 3
1 46.17.200.254 r1.skbkontur.ru 49675 0.666 ms 0.595 ms 0.659 ms
2 10.1.1.9 6.243 ms 0.88 ms 0.795 ms
3 10.1.1.190 0.405 ms 0.287 ms 0.313 ms
4 10.1.2.5 0.697 ms 0.648 ms 0.739 ms
5 195.208.210.26 msk-ix.airtel.com 49.337 ms 49.216 ms 49.533 ms
6 182.79.224.25 9498 177.448 ms 177.628 ms 178.535 ms
7 125.21.13.70 9498 171.579 ms 171.015 ms 170.99 ms
8 17.0.17.114 714 193.404 ms 192.903 ms 192.572 ms
9 17.0.16.190 714 200.347 ms 200.487 ms 200.928 ms
10 17.0.16.191 714 209.436 ms 206.797 ms 206.885 ms
11 17.1.108.1 714 189.432 ms 189.257 ms 189.172 ms
Initial latency is 49ms as packets hit Airtel in MSK-IX. This could be because either it’s remote peering a sub-optimal return route or just Russian geography adding latency to reach Moscow.
Based on 20-30 traces, this appears to be a typical setup with multiple routing points, and MSK-IX being one of them.
Let’s check for routing in the direction of Airtel India -> Russia. Fortunately, I have an Airtel FTTH connection at home as one of the backup links. Now, let’s run an MTR towards one of Ultra-Telecom’s gateway IPs (176.124.147.238).
1.|-- 172.16.36.1 0.0% 10 0.3 0.3 0.2 0.5 0.1
2.|-- 172.16.4.1 0.0% 10 0.7 0.8 0.7 0.9 0.1
3.|-- abts-north-dynamic-255.47.161.122.airtelbroadband.in 0.0% 10 15.1 13.9 12.1 15.4 1.1
4.|-- 125.18.73.17 0.0% 10 12.0 14.1 12.0 19.4 2.2
5.|-- 116.119.68.57 0.0% 10 156.3 158.6 155.1 175.8 6.2
6.|-- msk-ix-g1.union-tel.ru 0.0% 10 213.3 213.3 211.7 215.2 1.3
7.|-- root.ultra-telecom.ru 0.0% 10 205.7 204.5 203.4 206.1 1.1
Hop 3 & 4 are in Delhi (a bit high latency when testing from Rohtak but it is a known case as they route entire Haryana traffic via Chandigarh/Mohali) to Delhi. Hop 5 - somewhere outside India and hop 6 is the destination network on the MSK-IX peering IP. So if hop 5 is in Europe or Dubai - it’s a remote peering. If hop 5 is in Russia, it’s likely not a case of remote peering. Not much in between due to the usual MPLS tunnels.
Trace to 116.119.68.57 via my server in the EU:
1.|-- 172.17.0.1 0.0% 10 0.1 0.1 0.1 0.2 0.0
2.|-- ip-161-97-128-12.static.contabo.net 0.0% 10 0.4 0.7 0.4 1.9 0.5
3.|-- 10.0.50.1 0.0% 10 0.4 0.4 0.3 0.7 0.1
4.|-- 5-2-2.ear2.Dusseldorf1.Level3.net 40.0% 10 0.6 1.6 0.4 5.1 1.8
5.|-- ??? 100.0 10 0.0 0.0 0.0 0.0 0.0
6.|-- ae3.cr2-fra6.ip4.gtt.net 0.0% 10 12.5 8.1 4.1 25.1 6.5
7.|-- ae18.cr11-lon2.ip4.gtt.net 0.0% 10 14.5 16.8 14.5 21.8 2.7
8.|-- ip4.gtt.net 0.0% 10 14.9 16.7 14.9 22.6 2.4
9.|-- 116.119.68.57 0.0% 10 15.0 17.6 15.0 25.0 3.5
15ms from Dusseldorf. Seems like IP in London. This gives the impression that Airtel is doing remote peering at MSK-IX via London.
Another way to check here is to ping Airtel’s IP at MSK-IX - 195.208.210.26. In most cases, an IX IP will not ping but still, there can be a few cases which actually have the IX route in their table. I triggered a measurement from RIPE Atlas probes in Russia here. The lowest latency I see is 44ms and that again hints non-local / London.
Is it just for peering or a possible transit angle to it?
So is this capacity purely for peering or is Airtel possibly selling IP transit in Russia?
From various routing data collectors, Airtel has 131 Russian adjacencies i.e. Airtel is either peering (bilateral session or via route server) or selling transit to these. These 131 adjacencies are listed here.
Now if any of these are downstream - we should see those routes on the other side i.e. peers of Airtel as well as upstream. Since Airtel is known to be doing selective routing i.e. some routes go to one upstream, some to another, the upstream check may not be ideal and is actually more time-consuming. Airtel does not feed any of the RIPE RIS collectors directly but I have seen some of their peers (and upstream) feeding routes.
I can simply pick routes from anyone who is a peer of Airtel and has 20k+ routes in their table from AS9498. Picking any random IP from their large origination - 59.144.139.0/24
Let’s look for this route via Hurricane Electric’s super-looking glass.
One of the routes seems to be:
Prefix: 59.144.139.0/24
NEXT_HOP: 5.57.81.216, Learned from Peer: 5.57.81.216 (35266 - EX Networks Limited)
PATH_ORIGIN: IGP, RPKI: VALID
AS_PATH: 35266 9498
35266 - EXN-AS, GB
9498 - BBIL-AP BHARTI Airtel Ltd., IN
COMMUNITIES: 8714:65010 8714:65012 9498:3 9498:44 9498:91 34111:9498 34911:9498 35266:70 35266:110 40505:9498
8714:65010 - Announcement of a route to 65010
8714:65012 - Announcement of a route to 65012
LARGE_COMMUNITIES: 8714:1000:1 8714:1001:2
Source: rrc01.ripe.net
Last Updated: 6/21/2024, 11:26:45 AM (17w06d15h)
From community tags, this seems to be learnt via LINX. So AS35266 in London is learning the route via Airtel and feeding to RRC01. Upon inspecting it shows me 21743 routes which seems like a decent number as a start. These 21 routes are spread across 789 adjacencies of Airtel. A quick check shows me none of these are from Russia. I did the same hit and trial with one more peer and got similar results.
Thus one can conclude that either Airtel is not selling transit in Russia at all (for now ) or selling transit to extremely limited networks where routes are not hitting networks wide enough to be detected for now.
Summary and Conclusions
- Airtel is peering at MSK-IX Russia with a 100G port.
- Highly likely it’s a remote peering setup via London and routing itself is: India - London - Moscow.
- There seem to be some alternate paths via Dubai as well but it’s unclear if those are via IX.
- For now it seems to be a case of peering only with no transit.
Disclaimer: The views expressed on this blog are my own and do not reflect those of my employer.