June 27, 2009

Next Generation Addressing - IPv6

The current version of the Internet (known as version 4 or IPv4) uses a 32-bit IP addressing system, means Ipv4 can only produce address up to 2^32 i.e. in binary number system 32 times 1 i.e. 4,294,967,296. Even though we cannot use all these addresses because millions of addresses are reserved for private networks and multi cast addresses.
For example, the IP address is reserved for the default network, the address is used for loopback(localhost) address and the address is used for broadcasts
If we compare this with our Postal system, this is similar to the postman can identify 4,294,967,296 correct home address but if more than these addresses are present then how postman can deliver a post??? So we need the postman who can identify more addresses than 4,294,967,296. This introduces out new addressing system call as Internet Protocol Version 6. IPv6 uses 128-bit addressing system, so IPv6 can produce 2^128 unique addresses i.e. 128 times 1
i.e. 340,282,366,920,938,463,463,374,607,431,768,211,456
The tremendous growth in mobile devices including cellular phones, notebooks, computers, and wireless handheld devices has created a need for additional blocks of IP addresses. The website http://www.internetworldstats.com/stats.htm shows 1,596,270,108 Internet users in the world by March 2009.One day it will cross the mark of our limited IP addresses(i.e. 4,294,967,296).Before the IP will be exhausted we should ready with the solution i.e. IPv6.Some organizations are predicting that IP will be exhausted in 2012 or 2013.
The Internet Engineering Task Force adopted "IP Next Generation" (IPng) on July 25, 1994, with the formation of several IPng working groups. By 1996, a series of RFCs were released defining Internet Protocol Version 6 (IPv6), starting with RFC 2460.
Incidentally, the IPng architects could not use version number 5 as a successor to IPv4, because it had been assigned to an experimental flow-oriented streaming protocol (Internet Stream Protocol), similar to IPv4, intended to support video and audio.
The following advantages are immediately obvious in the new scheme of things:
Þ Larger address space
Þ Support for mobile devices
Þ Simplified address auto-configuration
Þ Improved address management
Þ Built-in security with end-to end IP Sec
Þ Enables more levels of hierarchy for route aggregation
IPv6 addresses are normally written as eight groups of four hexadecimal digits, where each group is separated by a colon (:). For example,
IPv6 also implements new features that simplify aspects of address assignment (stateless address auto configuration) and network renumbering (prefix and router announcements) when changing Internet connectivity providers. The IPv6 subnet size has been standardized by fixing the size of the host identifier portion of an address to 64 bits to facilitate an automatic mechanism for forming the host identifier from Link Layer media addressing information (MAC address).
The 2008 Summer Olympic Games were a notable event in terms of IPv6 deployment, being the first time a major world event has had a presence on the IPv6 Internet at http://ipv6.beijing2008.cn/en (IP addresses 2001:252:0:1::2008:6 and 2001:252:0:1::2008:8) and all network operations of the Games were conducted using IPv6.[29]It is believed that the Olympics provided the largest showcase of IPv6 technology since the inception of IPv6.
In 1997, IBM became the first commercial vendor to support IPv6 through its AIX 4.3 operating system. The latest version of Microsoft's Windows operating system, Windows Vista, has full IPv6 support enabled by default.

June 18, 2009

MS Word Page Number Rearrange Problem

While working with Microsoft Office Word 2003, I found a problem in page number system.
If you assemble a word document from various document with page number applied to them then it is very difficult to arrenge them in the new page number order.
e.g. If you take some pages from document1.doc with page numbers 1 to 10 also you take some pages from document2.doc with page number 35 to 40 and save in the new document let's say document3.doc . Now you want to arrenge the them from 1 to 16(10+6) then you are in big trouble.

I tried to delete page number and to give fresh number but I couldn't.I didn't any straight forward solution. I and my colleague(Rajesh) found a solution for that.You want to change page number 35 with page number 11 so go to page number 35 select the footer section now your page number gets highlighted then go to Insert -> Page Number -> Format then in Start at section change the number 35 to 10(not 11) then Ok -> Ok. Now you will see the magic that page number 35 converted to 11 and so on.

Try this and tell me are you suceeded or not???
If you know better solution for this then please share with me on my email - tushar.chaudhari.2k7@gmail.com

June 9, 2009

Gmail VS google mail

Do you know the difference between Gmail and Google mail?
Here is the explanation......

Both gmail.com and googlemail.com are the same domain name.The only difference is, if the user create account from the countries like England or Germany(means user uses IP of these countries) then they allocated as googlemail domain. Except that user allocated as gmail domain.

Once user gmail domain alloted then if user moved to England or Germany then he/she should not change the domain.

June 2, 2009

Invisible Web

Many untrained users have the naive expectation that they can locate anything on the world wide web by using Google or Yahoo or Ask.com. No, as powerful as these search engines are, they do not index everything on the world wide web. In fact, search engines index less than 10% of the entire web! That remaining 90% is called the "Invisible Web", or in other words, "The Cloaked Web" or "The Deep Web". This is the massive content that is publicly available, but hidden from regular search engines.

Indeed, this is a tough concept to grasp - that billions of web pages cannot be found by Google. But it's true, billions of pages are beyond the abilities of search engine cataloging. The robot "spiders" which scan and catalog the world wide web are limited... they cannot see nor index everything.

To better visualize this concept, let's start with some size estimates from Google.com, Yahoo.com, Cyberatlas, and MIT. These stats are current to Fall 2007:
Google.com indexes 12.5 billion public web pages.
71 billion static web pages are publicly-available. These pages can easily be found by Google and other search engines. (e.g. www.honda.com, www.australia.gov.au)
6.5 billion static pages are hidden from the public. As private intranet content, these are the corporate pages that are only open to employees of specific companies. (e.g. employees.honda.com, secure.australia.gov.au)
220+ billion database-driven pages are completely invisible to Google. These invisible pages are not the regular web pages you and I can make. Rather, these are dynamic database reports that exist only when called from large databases.
(e.g. custom online car quote for Shelly, Australian government discussion on aboriginal taxation)

Google, considered the best search database today, can only catalog a fraction of this monstrous content. Even with electronic spiders to catalog millions of web pages each week, Google current indexes only 12.5 billion out of the 220+ billion pages out there...less than 6% of all available internet content.

So if Google only catalogs 6% of the World Wide Web, and other search engines catalog even less, then where is the remaining 90%of web content hidden?

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