Computer Tierra

Monday 2 October 2017

IPv4 vs IPv6

What is IPv4 (Internet Protocol Version 4)?

IPv4 (Internet Protocol Version 4) is the fourth revision of the Internet Protocol (IP) used to to identify devices on anetwork through an addressing system. The Internet Protocol is designed for use in interconnected systems of packet-switched computer communication networks (see RFC:791).

IPv4 is the most widely deployed Internet protocol used to connect devices to the Internet. IPv4 uses a 32-bitaddress scheme allowing for a total of 2^32 addresses (just over 4 billion addresses). With the growth of theInternet it is expected that the number of unused IPv4 addresses will eventually run out because every device -- including computers, smartphones and game consoles -- that connects to the Internet requires an address.

What is IPv6 (Internet Protocol Version 6)?

A new Internet addressing system Internet Protocol version 6 (IPv6) is being deployed to fulfill the need for more Internet addresses.

IPv6 (Internet Protocol Version 6) is also called IPng (Internet Protocol next generation) and it is the newest version of the Internet Protocol (IP) reviewed in the IETF standards committees to replace the current version of IPv4 (Internet Protocol Version 4).

IPv6 is the successor to Internet Protocol Version 4 (IPv4). It was designed as an evolutionary upgrade to the Internet Protocol and will, in fact, coexist with the older IPv4 for some time. IPv6 is designed to allow the Internet to grow steadily, both in terms of the number of hosts connected and the total amount of data traffic transmitted.

IPv6 is often referred to as the "next generation" Internet standard and has been under development now since the mid-1990s. IPv6 was born out of concern that the demand for IP addresses would exceed the available supply.

The Difference Between IPv4 and IPv6 Addresses

An IP address is binary numbers but can be stored as text for human readers. For example, a 32-bit numeric address (IPv4) is written in decimal as four numbers separated by periods. Each number can be zero to 255. For example, 1.160.10.240 could be an IP address.

IPv6 addresses are 128-bit IP address written in hexadecimal and separated by colons. An example IPv6 address could be written like this: 3ffe:1900:4545:3:200:f8ff:fe21:67cf (see "What does an IPv6 address look like?")

Did You Know...?

IPv6 in the News: (April, 2017) MIT announced it would sell half of its 16 million valuable IPv4 addresses and use the proceeds of the sale to finance its own IPv6 network upgrades.

Difference between RAM and ROM

Effa Linggahan 20:43 5 Comments

Read-only memory, or ROM, is a form of data storage in computers and other electronic devices that can not be easily altered or reprogrammed. RAM is referred to as volatile memory and is lost when the power is turned off whereas ROM in non-volatile and the contents are retained even after the power is switched off.

Random-access memory, or RAM, is a form of data storage that can be accessed randomly at any time, in any order and from any physical location in contrast to other storage devices, such as hard drives, where the physical location of the data determines the time taken to retrieve it. RAM is measured in megabytes and the speed is measured in nanoseconds and RAM chips can read data faster than ROM.

Comparison chart

RAM versus ROM comparison chart
	RAM	ROM
Definition	Random Access Memory or RAM is a form of data storage that can be accessed randomly at any time, in any order and from any physical location., allowing quick access and manipulation.	Read-only memory or ROM is also a form of data storage that can not be easily altered or reprogrammed.Stores instuctions that are not nescesary for re-booting up to make the computer operate when it is switched off.They are hardwired.
Stands for	Random Access Memory	Read-only memory
Use	RAM allows the computer to read data quickly to run applications. It allows reading and writing.	ROM stores the program required to initially boot the computer. It only allows reading.
Volatility	RAM is volatile i.e. its contents are lost when the device is powered off.	It is non-volatile i.e. its contents are retained even when the device is powered off.
Types	The two main types of RAM are static RAM and dynamic RAM.	The types of ROM include PROM, EPROM and EEPROM.

Types of Network Topology

Effa Linggahan 20:28 14 Comments

A network topology is the arrangement of a network, including its nodes and connecting lines. There are two ways of defining network geometry: the physical topology and the logical (or signal) topology.

The physical topology of a network is the actual geometric layout of workstations. There are several common physical topologies, as described below and as shown in the illustration

In the bus network topology, every workstation is connected to a main cable called thebus. Therefore, in effect, each workstation is directly connected to every other workstation in the network.

In the star network topology, there is a central computer or server to which all the workstations are directly connected. Every workstation is indirectly connected to every other through the central computer.

In the ring network topology, the workstations are connected in a closed loop configuration. Adjacent pairs of workstations are directly connected. Other pairs of workstations are indirectly connected, the data passing through one or more intermediate nodes.

Above are the common topology that is often asked and stated. But then , there are other topology also :)

If a Token Ring protocol is used in a star or ring topology, the signal travels in only one direction, carried by a so-called token from node to node.

In the bus network topology, every workstation is connected to a main cable called thebus. Therefore, in effect, each workstation is directly connected to every other workstation in the network.

If a Token Ring protocol is used in a star or ring topology, the signal travels in only one direction, carried by a so-called token from node to node.

The mesh network topology employs either of two schemes, called full mesh and partial mesh. In the full mesh topology, each workstation is connected directly to each of the others. In the partial mesh topology, some workstations are connected to all the others, and some are connected only to those other nodes with which they exchange the most data.

The tree network topology uses two or more star networks connected together. The central computers of the star networks are connected to a main bus. Thus, a tree network is a bus network of star networks.

Logical (or signal) topology refers to the nature of the paths the signals follow from node to node. In many instances, the logical topology is the same as the physical topology. But this is not always the case. For example, some networks are physically laid out in a star configuration, but they operate logically as bus or ring networks.

Monday 25 September 2017

Interesting Facts About Internet

Effa Linggahan 20:07 28 Comments

1. According to Google, the internet consisted of 5 Million Terabytes of Data way back in 2010.

— The most surprising fact is that Google itself said that they had indexed just 0.004% of all the content present on the internet. As of September 4/2015, the number of pages that exist on the web is 45+ Billion pages. That’s huge!

2. As of Sept 2014, There are more than a billion websites on the Internet.

— To add more numbers to the data, As of 20 February 2014, there were around 172 million Tumblr blogs on the web. 75.8 million Blogs and Business sites in existence are on WordPress. Moreover, more than 2 million blog posts are published every single day.

3. 3.1 Billion out of the 7 Billion people on earth is already online.

InternetLiveStats (ILS) monitors the live state of the internet, and as of Sept 5, 2015, there are 3,197,308,895 users on the web. This is expected to grow even more by the year 2020.

4. 30,000+ Websites are hacked every day.

We don’t want anyone’s site to get hacked up, however looking at the total number of sites on the internet; this number is pretty low. We guess webmasters and the service providers are getting more secure.

5. Approximately 5000 domain names are registered every hour.

That translates the number to a whopping 120,000 Domains every single day and 43 Million domain names a year. The greatest irony is that more than 75% of Domains are not live. They are simply parked or not at all resolving, that’s the reason why you don’t get your desired .com domain.

6. Facebook boasts of a massive 1.44 Billion users.

Approximately 18% of the world’s population is available on Facebook. There were 968 million daily active users on average in June 2015. The most shocking stat is that almost 844 million of them were mobile daily active users.
Statistics suggest that around 50% of Internet users are on Facebook.

7. The first ever email was sent in 1971.

The email was sent by Ray Tomlinson (US programmer) who invented the email system. The “@” symbol was used to the symbol was used to signify that the email was sent to a person and not a dumb machine. However, he says that he doesn’t remember the exact message he had sent back then.

8. 250 Billion emails are sent out daily.

— No, these shocking numbers aren’t triggered by humans. The surprising fact is that 81% of all those emails are spam which is sent using automated means. That’s a whopping 200 Billion spam mails every day.
Let us tell you more about spam messages. The first spam email was sent back in 1978 for DEC System 2020. The email contained 600 recipients, and none of them were happy to receive it. 😛

9. The world’s first website is still online.

The first website created was info.cern.ch, and it is still online and working fine. It is a very basic HTML site, and the page contains few lines of text. The page was written with the help of the first version of HTML.

10. Twitter was earlier known as Twttr.

Twitter was first described as an SMS-based social networking and, therefore, has a character limit of 140. The first tweet was by Jack Dorsey on March 21, 2006. The tweet read “just setting up my twttr.” The site has evolved a lot in the recent years and now has more than 250 million active users. There are more than 500 million tweets shared every single day.

11. Garfield the cartoon once offered its own Email service.

Yes, Garfield, the cartoon character was offering an email service named GMail.com. Google later acquired the service, and they renamed it to Google Mail (GMail.com) as we all know today. We don’t know if that service would/would not have been so popular if it wasn’t acquired by Google.

12. 72 Hours of video contents are uploaded on YouTube Every minute.

By the time you reached this paragraph, 150+ Hours of videos have already been uploaded to YouTube. Speaking about user engagement, the massive video sharing site serves 1 Billion people every month, and an average internet user spends 4 hours every month on YouTube.
Looking at such stats, Google has taken massive steps to protect copyrights of individuals by scanning over 100 years of video contents every day using complex software.

13. There are more than 1.5 Million apps on both Google Play and iTunes Store

As of June 8, 2015, 100+ billion apps were downloaded from the iTunes Store. Unfortunately, we don’t have the fresh data about Google Play. However, the recent data tells us that there have been 50+ Billion downloads on the play store till date. Both of them shares one common moral — The market for apps is as huge as websites on The internet.

14. Around 80% of the images available on the internet are of Naked women.

The internet is pretty much attracted to naked ladies and explicit materials. We did a bit research on this, and the data seems believable. We have few more shocking stats to share with you regarding inappropriate contents. Here they are:
12% Of all existing websites online are currently NSFW.

1 out of every three downloads is NSFW content.

Sunday is the day of maximum consumption.

The online adult industry makes 3000$ a second.

15. 51% of all internet’s traffic is Fake.

Humans only make up 49% of the entire traffic; the rest are triggered by various bots and spamming software. No doubt, we would be having faster connectivity If they weren’t leeching on bandwidths.

16. The Internet took just 4 years to reach its first 50 Million Users.

Television took 13 years. While the radio took 38 years to reach the same amount of users. That’s cool!

17. 7 People control the whole internet.

Yes, you heard it right. There are seven people assigned to the Internet Corporation for Assigned Names and Numbers (ICANN) who hold seven different keys. In the case of Catastrophe, these seven people can meet again and restore the state of Internet. There are seven more copies of the original key in case if any one of them gets misplaced or if something goes wrong.