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.
APNIC and RIPE NCC are doing a hackathon at APRICOT 2018. It just started today with some light interaction with various participating members yesterday. The theme of the hackathon is around IPv6. Many cool projects were suggested yesterday and teams started working today on certain shortlisted projects like:
Let’s see how things go in next 12hrs. Super fun. Things should show up on Github in next few hours. :)
Saw this excellent presentation in UKNOF 34 by Peter Stevens from Mythic Beasts. Really enjoyed the challenges and fixes he shared in running an IPv6 only web hosting. A must watch for geeks :)
Also, UKNOF & NLNOG both seem to have excellent content in their conferences along with professional video recording which they make available over YouTube channels.
One of my friend went for a VM with a German hosting provider. He got single IPv4 (quite common) and a /64 IPv6. Overall /64 per VM/end server used to be ok till few years back but now these days running applications inside LXC containers (OS level virtualization) make more sense. This gives option to maintain separate hosting environment for each application. I personally do that a lot and infect blog which you are reading right now itself is on a LXC container.
VyOS is quite interesting OS. It’s a open source Linux based network operating system based on Vyatta. It’s config style seems bit like JunOS in terms of hierarchy and set/edit/delete options while editing configuration.
**Can one use it in a small ISP or a Corporate LAN setup?
Someone asked me recently if we can have complete open source based router in smaller network doing basic stuff. Not with not-so-streamlined Linux shell but networking OS where network engineers favorite tool “?” works in CLI with options. Let’s take a possible case with bunch of routers, a server with speedtest-mini running on it and end desktop with Ubuntu-desktop on it along with VyOS based router. Goal here is to have basic features to work (to start with!). I am conducting this test and setup on the VM infrastructure at home but that should have zero impact/configuration of network devices and hence not going to focus on that part. All devices including server, desktop and router are pretty much running on virtual machines or KVM containers. To configure and test:
One of very cool features of IPv6 is link-local address which stays local to a given link. For this fe80::/10 is reserved. A /10 is a huge amount of address space in IPv6 (and in IPv4 too :) ). This means from fe80:0000:0000:0000:0000:0000:0000:0000 to febf:ffff:ffff:ffff:ffff:ffff:ffff:ffff.
Since by design link-local address stays local, the address configured on the upstream/gateway router can be kept same for ease of use and comfort. This wasn’t the case of IPv4 where each VLAN/layer 2 domain had it’s own gateway. So e.g if you have two VLANs or interfaces say: Gi1/0 and Gi2/0. You decide to use 10.100.100.0/30 on Gi1/0 and 10.100.100.4/30 on Gi2/0.