Posts

Finding IPv6 from IPv4 address of a host

One of my friend asked me an interesting question about relating IPv4 with IPv6. His question was: in dual stack setup, if we have IPv4 of a router/host, how can we find IPv6 associated with it?

Well, as far as I know there’s no direct way to relate IPv4 with IPv6 but there’s a nice trick out. Say e.g we have Google Public DNS operating at IPv4 - 8.8.8.8. To find IPv6 address of same server (if it exists at all), we can lookup for reverse DNS to get hostname, 

Thoughts on NKN - National Knowledge Network

You might have heard of NKN i.e National Knowledge Network by Govt. of India. Overall idea of NKN was to connect all educational institutions within country including all IIT’s, IIM’s, NIT’s and various govt. universities on fiber at 1Gbps speed. Though little late and crazy way of solving problem, but still NKN is nice effort from Mr Sam Pitroda.

I was talking to a friend from IIT Delhi last week, and here’s his speedtest.net result from his room (yeah room, not any lab!)

Simple bash script for IP-ASN mapping

Whenever I see a new unknown IP range, it gets hard to find exact source of that IP within command shell. Recently, I found a very interesting source of that information from Team Cymru.

I figured out (with a friend’s help) that using their whois server - v4.whois.cymru.com one can actually grab limited information as required. 


E.g

anurag@laptop:~$ whois -h v4.whois.cymru.com "  -v 8.8.8.8"
AS      | IP               | BGP Prefix          | CC | Registry | Allocated  | AS Name

15169   | 8.8.8.8          | 8.8.8.0/24          | US | arin     | 1992-12-01 | GOOGLE - Google Inc.

As we can see -v gives all possible information. All I needed was AS number, AS Name, BGP Prefix, Country code - this gives enough information for an IP address. Thus command turns out to be with -c & -p.

End of inter-circle roaming: Good or Bad move?

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.  


Little background

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.

Start of competition based on speeds

Yesterday I read about BSNL increasing speeds from 512Kbps to 1Mbps (with caps). Today I came across news in Business Line about Bharti Airtel increasing speed on wireline DSL. This is really good believe me! I am not refering to little bit increase in speeds, but I am refering to start of competition within ISP’s based on speed. Right now it’s Wireless (3G) Vs Wireline (DSL) players, and I am sure very soon we will see competition within wireline Vs wireline players. Competition is always good specially in telecom industry. We can clearly see where we stand now: from 8years of waiting for a telephone connection to 5min of prepaid sim purchase, from 56Kbps at $1/hour to 10GB data at $20 a month. We have came so far, but yet long way to go!