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Friday, July 29, 2011

IPv6 made simple & easy. No,...not the transition [you wish!] The explanation

June 8 has been recognised as the World IPv6 day. The recognition of the significance of the day, though, is mostly restricted to individuals involved in the running & upkeep of the network & enterprises who depend on the Internet - cloud computing, web hosts, online services & their kind. Basically people working behind the scenes to ensure you experience an uninterrupted & uninterruptible Internet connection.

However, the continued growth & evolution of the Internet depends upon a successful, & desirably smooth, migration & adoption of the IPv6 standard. With each passing day, the footprint of our online activities & number of devices we use to go online are only increasing. The use [&, often, abuse] of the internet is steadily creeping into increasing aspects of our lives & our dependence on the Internet to get work done too is on a steady ascent. Thus, knowing about IPv6 [Internet Protocol version 6], even if a little bit, is critical for the continuation of our way of life useful.

A simple, easy-to-understand explanation of the IPv6 & its use has been illustrated in this infographic.

Click on the image to view a larger-sized image

Simple & easy explanation of IPv6 [Infographic]

via Focus

An infographic explaining the need to migrate to IPv6

Click on the image to view a larger-sized image

Why is there a need to migrate to IPv6 [Infographic]

via AT&T

IPv4 is being succeeded by IPv6...err, poor counting skills? what-evah happened to the IPv5?

Currently following the IPv4 standard, it would be logical to assume the one succeeding it would thus be termed IPv5. However, as we now know, it is IPv6 that is all set to take its place. No, it does not have anything to do with IPv5 being numerologically inauspicious or some such other mind-whacking, gobbledygook explanation.

The reason for this is because [not-so] long years ago, when we made a tryst with Internet, we had to formulate effective set of rules [protocols] for communicating with & over the Internet. Thus, as part of specifying such a set of rules, the Internet Stream Protocol was proposed. It was generally identified as ST. A later iteration of the protocol, ST-2 was also identified as Internet Protocol version 5, that shortens to IPv5.

As a result, when time came to name the successor to IPv4, in order to avoid confusion with ST-2 that was an unrelated protocol, the good folks at the Internet Engineering Task Force [IETF] decided to name theirs IPv6.

How is IPv6 important to the end-user [you, me, your neighbor's hawwwtt wife-kind of people] & what if the transition does not take place?

Transition has to take place & will take place. Continuing with IPv4 is not an option, unless growth of the Internet is to be capped - an impossibility, or some way is found to scale it up to match that of IPv6 without hampering its performance. However, no such method is currently available. Questions whose answers, however, are being debated is the manner in which the migration process is to be undertaken.

Comparison between IP address allocation capability in IPv4 & IPv6

image via: IPv6 with Henry Yu

Yet for the sake of argument, let us consider a hypothetical scenario where no such transition is to take place & people are to continue with the IPv4 standard currently in effect. As indicated in the infographic above, any 2 internet-enabled devices, in order to be able to communicate with one another, must have an IP address assigned to it, for identification, during that session of communication.

With the number of possible IP addresses that can be generated under IPv4 reaching its limits, a situation would arise in the not so distant future when a device that wishes to connect to the Internet finds that its ISP does not have any IP address left to allocate to it [dynamically assigned IP addresses, a practise itself borne out of the need to make effective use of IP addresses & avoid surplus capacity]. Thus with no IP address available, the device would therefore be unable to log on to the Internet - BUMMER!! Workarounds deployed even now to prolong use of IPv4 are known to render number of Internet services unusable.

4,29,49,67,296 [~4.3 billion] IP addresses can be generated (232) following in the IPv4 standard & they have been estimated to be used up by within a year from now.

IPv6, on the other hand, can generate 3,40,28,23,66,92,09,38,46,33,74,60,74,31,76,82,11,456 unique IP addresses 2128 [~340 trillion trillion trillion or 340 Undecillion - a number so large, even Microsoft can't comprehend it - Live Writer marks Undecillion as a typo] - enough for handling the estimated increase in Internet usage.

Related: IPv4 address exhaustion

What is IPv6 - an explanation

Also watch: World Tests IPv6: Why 4.2 Billion Internet Addresses Just Weren't Enough

Cool. So lets all jump into the IPv6 bandwagon then. What's the problem?

The simplest & the most important reason - *cost*. Enterprises migrating to the IPv6 standard would have to undertake acquisition & setting up a whole new set of software platform & network hardware infrastructure, including DNS servers, capable of handling Internet traffic through IPv6. The cost of such an undertaking would quite easily run upwards of multi-millions of American dollars [not Zimbabwean], depending on the scale of operation. Say an enterprise does setup its IPv6 infrastructure and is all ready to connect to the internet an go about its business as before. But can it? Barely. This is because while it itself migrated to IPv6, other networks with which it had been communicating have not yet done so, possibly owing to the costs incurred. An IPv6-based network can only communicate with other IPv6-based networks. It has not been designed to communicate with an IPv4 network.

In order to overcome this "oversight", new instruction-sets have been devised to get them to talk to each other. However using such an interface increases latency, besides degrading the performance. Thus in order to ensure optimal performance while communicating with an IPv4 network, the enterprise that had migrated to IPv6 may just decide to retain its earlier IPv4 infrastructure & operate it alongside when the need arises - thereby essentially doubling cost of operation - now why would anybody want to be an early adopter?

Errr...okay then, but how do I know if my ISP is an early adopter and supports IPv6?

If you can open Google's IPv6 site, you are good to go:

India, meanwhile has set itself a target of March 2012 for a full roll-out of IPv6.

The National internet Exchange of India [NIXI] is setting up the required infrastructure & conducting training to enable & help adoption of the IPv6 standard - details.

On a related note, check out this inforgraphic prepared by Cisco titled, "The Internet of Things"

Infographic - growing expanse of the Internet

A data from the infographic,

By the end of 2011, 20 typical [American] households will generate more Internet traffic than the entire Internet in 2008

I've added the words inside the parentheses.


Wednesday, July 27, 2011

Indian Navy & Air Force's MiG-29 aircrafts [hi-res photographs]

A collection of hi-resolution pictures of the variants of the MiG-29 aircrafts in operation with the Indian Navy & Indian Air Force.

The Indian Air Force [IAF] has been operation the MiG-29 aircrafts since the mid-80s, a purchase decision made in response to the Pakistan Air Force receiving, from the U.S, Lockheed Martin's F-16 multi-role combat aircraft [variants of which, received in the 90s, bore an uncanny resemblance to soybeans - shape-shifting technology anyone?!].

The Indian Navy [IN], on the other hand, has contracted RAC MiG to acquire 45 of these aircrafts for operating off its long delayed, not yet inducted Aircraft Carrier, INS Vikramaditya [formerly an Aircraft Cruiser Admiral Gorshkov, renamed from its original name Baku]. Hopefully no subsequent Aircraft Carrier it plans to build and operate [IAC-1&2] would carry them as the sole aircraft - successful induction of the Naval version of the Light Combat Aircraft [LCA] could see them operating in a hi-lo configuration alongside the MiG-29s.

The Indian Navy's MiG-29 are designated MiG-29K [single-seat] & MiG-29KUB [twin seat]

click on the thumbnails to view larger-sized pictures

20110727-Indian-Navy-MiG-29-K-MiG-29-KUB-01 20110727-Indian-Navy-MiG-29-K-MiG-29-KUB-09
20110727-Indian-Navy-MiG-29-K-MiG-29-KUB-04-TN 20110727-Indian-Navy-MiG-29-K-MiG-29-KUB-11
20110727-Indian-Navy-MiG-29-K-MiG-29-KUB-10 20110727-Indian-Navy-MiG-29-K-MiG-29-KUB-02-TN
20110727-Indian-Navy-MiG-29-K-MiG-29-KUB-03-TN 20110727-Indian-Navy-MiG-29-K-MiG-29-KUB-08
20110727-Indian-Navy-MiG-29-K-MiG-29-KUB-13-TN 20110727-Indian-Navy-MiG-29-K-MiG-29-KUB-12
20110727-Indian-Navy-MiG-29-K-MiG-29-KUB-06-TN 20110727-Indian-Navy-MiG-29-K-MiG-29-KUB-07-TN

IAF has been operating the MiG-29 [single-seat] & the MiG-29 UB [twin-seater aircraft]. As part of an agreement signed between Indian & Russia, IAF's entire fleet of MiG-29s would be upgraded to match the standards & capabilities of the latest variant of the MiG-29, the MiG-29 SMT. The upgraded aircraft would be designated MiG-29UPG [single-seat] & MiG-29UPG UB [twin-seater].

click on the thumbnails to view larger-sized pictures

20110727-Indian-Air-Force-MiG-29-UPG-01 20110727-Indian-Air-Force-MiG-29-UPG-04
20110727-Indian-Air-Force-MiG-29-UPG-06 20110727-Indian-Air-Force-MiG-29-UPG-03
20110727-Indian-Air-Force-MiG-29-UPG-02 20110727-Indian-Air-Force-MiG-29-UPG-05
20110727-Indian-Air-Force-MiG-29-UPG-07 20110727-Indian-Air-Force-MiG-29-UPG-09

via: || || || || || || ||

Also: Indian Navy MiG - 29K aircraft wallpapers

Uploaded a lecture where the Director of the Aeronautical Development Agency [ADA] spoke about technologies & features that are to become part of future airborne combat systems & the challenges that designers face in realising these technologies - Future Air Combat Systems - Technologies, Features & Challenges


Monday, July 25, 2011

On-Condition Maintenance of Aircrafts: An overview

Had been reading about the On-Condition Maintenance process over the weekend, since last week. Having read a fair amount of content, thought of putting what I've learnt and understood in writing, in order to consolidate what I've read about it. As my folks say, writing down what has been learnt improves learning & understanding.

Sunday, July 24, 2011

On-Condition Maintenance of Aircrafts: An overview 04 of 04

Previous: Part 01 - Part 02 - Part 03 - Acronyms
How to determine the point of replacement of component that is under On-Condition Maintenance?
The concept of P-F curve or degradation curve is used to determine the point of failure and thus before it, the point at which the component must be replaced as part of the On-Condition Maintenance process. The P-F portion of the curve indicates when a potential failure is first visible to us [potential failure point 'P'] and the operating condition where the equipment is rendered unusable due to its performance having degraded to unacceptable levels [functional failure point 'F'].

On-Condition Maintenance of Aircrafts: An overview 03 of 04

Previous: Part 01 - Part 02 - Acronyms
Time duration specified by the Dutch Civil Aviation authorities for performing monitoring & inspection as part of an On-Condition Maintenance programmes of some critical components are as follows:

On-Condition Maintenance of Aircrafts: An overview 02 of 04

Previous: Part 01 - Acronyms
However, as stated earlier, maintenance of not all systems and components can be transitioned to the On-Condition Maintenance standard. According to the Maintenance Directive NL-2010-001 issued by the Civil Aviation Authority of the Netherlands [CAA-NL] some components that may not be maintained by OCM are,

On-Condition Maintenance of Aircrafts: An overview 01 of 04

The Indian Air Force [IAF] is currently in the process of imparting a Mid Life Upgrade [MLU] to its entire fleet of the Russian origin MiG-29 multi-role combat aircraft. Included in the technology & capability upgrades being incorporated into the aircrafts, is the transition towards performing on-condition maintenance of the aircrafts from the traditional hard-time maintenance procedures currently being followed on the fleet.
Traditionally, life of aircraft components & their subsequent replacement have been specified in terms of Time Between Overhaul [TBO]. Such practice entails that the component in question be replaced or overhauled irrespective of their present state of performance & physical condition at that moment.

Monday, July 04, 2011

India's former Main Battle Tank [MBT] Vijayanta at Avadi [Photographs]

Found these pictures of the Main Battle Tank, Vijayanta, earlier in service with the Indian Army. These are licensed manufactured British Vickers Tanks that were later successfully adapted for use in varied configurations as Bridge laying, Armoured Recovery Vehicle etc. Successful demonstration involving incorporation of a more powerful & reliable power-plant & up-gunning its main gun to a higher caliber were also made, but did not find a favorable response from the end-user.

They were to be withdrawn from service by 2008. Counted four of them at my place, being used as monuments outside defence establishments - quite imposing, they look.

The Heavy Vehicles Factory [HVF] in Avadi [an acronym for Armoured Vehicles and Ammunition Depot of India], Tamil Nadu currently houses the country's only assembly line needed for putting together battle tanks in service with the Indian Army.

Click on the thumbnails to view larger-sized images

Main Battle Tank [MBT] Vijayanta [Vickers derivative] at Avadi factory Main Battle Tank [MBT] Vijayanta [Vickers derivative] at Avadi factory
Main Battle Tank [MBT] Vijayanta [Vickers derivative] at Avadi factory Main Battle Tank [MBT] Vijayanta [Vickers derivative] at Avadi factory



Friday, July 01, 2011

Create a shortened URL without signing in or signing up

Had been using the URL shortner bookmarklet for long for posting to Twitter. Recently  discovered that the bookmarklet was no longer doing so & was instead creating shortened URLs, both URL shortening services being run by the same enterprise. From now onwards, in order to create a URL, one has to sign in into the service & only then would it be possible to do so - *hate* signing in anywhere & avoid it as far as possible.

Turns out, as of the time of posting, & URLs are inter-changeable, i.e, if you had created a shortened URL, then it is possible to shave off 2 more characters by simply replacing the by without any change in result. Critical, if one posts on twitter, where character real-estate is a premium. However, with growing number of URLs being shortened with their service, it may be just happen that they decide to turn & URLs unique. Until that time, no signing-in required to create a shortened URL.


Original shortened URL:

a URL created by replacing the


Was looking up something, when I came across this site still hosted on Geocities. Ran a Google search query & found out, as the URLs above indicated, around 60,000+ sites continue to remain hosted on Geocities. This does not count their service in Japan, which they continue to run. However, considering the fact that Yahoo! was supposed to have shutdown, it was indeed surprising to find these pages still there. Will try searching around for an answer. Some kind soul could cut short my work & save me some time by posting the answer, in the comments below, though.