Last month I got access to Jio 5G like everyone else around in Haryana. They are running a beta program with uncapped data for now. Overall it works fine for usual stuff (web surfing on popular sites, YouTube videos, music streaming etc) but 464XLAT seems to be a little buggy in IPv4 hardcoded destinations. Initially it was giving quite a few issues but many of them seem to be fixed in last few days.
I am in Bangalore for two days. While there are many things packed into these two days short schedule, one of the most exciting ones is Google Global Network India Innovation Summit. While Google has presented across various events in past talking about their AS15169 backbone, this is the first summit where they are covering it in detail and that too with the Indian context!
Must say that I find AS15169 quite fascinating on the BGP side of things. A massive network which follows “cold potato” routing i.e keeping the majority of traffic over IGP over larger locations, terminating BGP sessions on the virtual appliance with SDN backing, a pretty robust failover design with BGP + DNS taking care of server(s) and even entire PoP failing. I blogged about them back in 2020 here. So this should be fun!
Lately, I have been struggling to keep latency in check between my servers in India and Europe. Since Nov 2021 multiple submarine cables are down impacting significant capacity between Europe & India. The impact was largely on Airtel earlier but also happened on Tata Comm for a short duration. As of now Airtel is still routing traffic from Europe > India towards downstream networks via the Pacific route via EU > US East > US West > Singapore path. Anyways, this blog post is not about the submarine cable issue.
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”?
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:
Often this comes into the subnetting discussion by my friends who are deploying IPv6 for the first time. How do you calculate subnets outside the 4-bit nibble boundary? This also happens to be one of starting points of APNIC IPv6 routing workshop where I occasionally instruct as community trainer.
In IPv6 context, it refers to 4 bit and any change in multiple of 4 bits is easy to calculate. Here’s how: Let’s say we have a allocation: 2001:db8::/32. Now taking slices from this pool within 4 bit boundry is quite easy. /36 slices (1 x 4 bits) 2001:db8:0000::/36 2001:db8:1000::/36 2001:db8:2000::/36 and so on… /40 slices (2 x 4 bits) 2001:db8:0000::/40 2001:db8:0100::/40 2001:db8:0200::/40 /44 slices (3 x 4 bits) 2001:db8:0000::/44 2001:db8:0010::/44 2001:db8:0020::/44 /48 slices (4 x 4 bits) 2001:db8:0000::/48 2001:db8:0001::/48 2001:db8:0002::/48 Clearly, it seems much simple and that is one of the reasons we often strongly recommend subnetting within the nibble boundary and not outside for all practical use cases. However understanding why it’s easy this way, as well as things like how to subnet outside nibble boundary for cases, say if you are running a very large network and have a /29 allocation from RIR.