Pages

Thursday, April 25, 2013

Animals in outer Space


Man’s dream of living and travelling through universe is a step closer now. With Russia’s BION- M1 satellite in space with animals and plants to study the effect of zero gravity and weightlessness . 
This is one of three BION satellites (animal-carrying space capsule) which space pioneering nation Russia has recently send in space on 18th April. Though this is not the first time a bio satellite is being sent in space. Russian bio satellite programs dates back to 1966, which was resumed in 1973.


This program is not only helping Russian but also NASA who is closely associated with these programs since 1971. They are trying to understand the fundamentals of space biology which may carter Russia’s aim of establishing a base on moon.

This Launch of Soyuz was also closely watched by the world, as now it’s the only working space shuttle on earth, frequently used to reach the ISS (International Space Station)and with the recent failures of Russian space program. 

On 18th, the Bion satellites or Bion space program, also named Bio cosmos, was launched from the Baikonur, Kazakhstan in Soyuz-2.1, after a delay of 3 years as initially it was to be launched in 2010. The biological research satellite is being sent to conduct experiments to make life of astronauts easier in outer space. The satellite carried a crew of 45 mice, 8 Mongolian gerbils, 15 geckos, snails, fish and microorganisms in it. These animals are luckier than Leila the first dog (animal) to being sent in space as that they will return back to earth.


The satellite is scheduled to return back to earth after 30 days, on 18th May with a help of a parachute. It’s after that scientist will be able to study the data gathered through the experiments. These experiments could not be carried on the international space station, because of the sanity issues these animals may create. It’s only after the analysis of the data, we can say about the productivity of such expensive launches.


Keep Looking …

Wednesday, April 24, 2013

Nitaqat , a dilemma for immigrants in gulf


For years, people for developing and under developed countries have been going to gulf countries for finding jobs and making their ends meet. This mainly consists of Expatriates and unskilled labourers. But now with the new policy of GCC and Saudi Arabia it might be difficult for people to work in gulf countries.

Few months ago, Saudi Arabia ‘s new policy named Nitaqat meaning  naturalisation which aims at providing work to its own national rather than others. According to the policy, each firm needs to employ a fixed percentage (10%) of Saudi nations. Not only this, the government has also fixed a 3000 Riyals per month salary for such employees. This is a great set back to the economy of small scale firms who use to employee people from Asia and other undeveloped countries at cheaper rates of 900- 1000 Riyals.  Though the step is to generate employment for their own people and is a result of internal politics , some people are seeing this as a step to restrict the number of immigrants coming to the country.


Likewise GCC members Bahrain, The Sultanate of Oman, Kuwait, Qatar and UAE  have also planned to implement a policy, according to which all those people who either are not working anywhere or does not possess the skills that they claim will be shipped back to their native places. This step has created a lot of unrest among the people working there and their families back at home.


A large number of people travel from India to the Gulf countries seeking jobs .Most of them are uneducated or unskilled .These people are the one facing huge crisis. Lakhs of people will be transferred back and they will have to find jobs in their own countries. With countries like India, where people aspire from the stories of  Industrialist like Dhirubhai Ambani ( who worked in Yemen , saved money  returned back and established the business which is today India’s biggest firms), it’s like shattering of dreams.  I guess people have to find some other place to work.


Keep Looking …

Are Gold Investing Schemes profitable to customers

We Indians are very much attached to the glitters of the yellow metal GOLD. From the birth of a child to the death of an elder , gold is entangled in our cultural as well as social life. When a child is born , things of gold are given to him for the prosperous future it might create for him . On his death we give away his gold jewellery with a view that he might use it in his afterlife. Marriage without gold , cannot be thought of in India .No matter how rich or how much poor you are , you need to have gold.

Gold is so  precious to us that all our  Gods and Goddess are laden with gold . Tirupati balaji temple.is one of the many other which has huge amount of gold reserves with them,  donated by the devotes . In fact TTD Tirumala Tirupati Devasthanams is the richest temple of the world with annual year of about 700 crores INR.


With such enthusiasm of gold , it natural for average Indian to horde gold. As a result . there are various schemes for the investors which wish to buy gold or invest in it.


In this article i will be talking about the the gold jewellery companies offering schemes like out of 12 installments pay for just 11 installments and rest one installment would be paid by the company. You'll own the gold jewellery after the completion of the tenure.


It kind looks interesting and profitable . but the question is to whom. Is it the customer or the marketer .In these particular schemes its more profitable to the dealer than the investors. And as a result you will find huge amount of such schemes springing up everywhere. 

Lets see closely what's happening in these deals.

Suppose you think of investing 2000 INR per month for 11 months so the total amount invested by you will be
 2000*11 = 22000  , 
to this amount the dealer adds another 2000 . Hence the total amount becomes 24000. 

You would see a profit of  
(2000/22000)*100= 9.09 %  
on your investment.which is clearly more than any prevailing RD ( recurring deposit ) Schemes but lesser than FD ( fixed deposit) .


Now comes the tricky point , with this money you can only buy jewelery and that too on the prevailing market price.that means if the price is up , you will have to pay the extra charge .

Firstly, Jewelry which is made up of 22k gold and also include making charges which varies from design to design . So if the main purpose is to invest then such schemes are not beneficial to you. It is much better to buy gold coins or bars instead of jewelry.

Secondly . the dealer also earns interest from your installments as he keeps in bank, which you could have earned .More over at the maturity you would have the option of using that money according to your new needs rather than being bounded into buying only jewelry.

Thirdly , the merchant is sure that you will have to buy from his shop as you cannot get it transferred  or get money in exchange.

Fourthly , you cannot have different time periods .i.e its just one year , you cannot extend it for another year nor can you re invest it. You have to take the jewellery after one year.

So not only the merchant is selling a 22k jewelry with approx 600 INR making charge but also earning interest from your installments.

Much better option for you would be to invest in ETF where you can invest monthly and en cash it any time and that too at market rate . Or e-gold is also a good alternative where you can buy gold on paper and have it in physical form as well. this is just my calculations and view , you are free  have a different view.


Keep Looking...



Monday, April 22, 2013

Just 50 seconds !!


Is maths an Indian thing? Is it our heritage and is that why Mathematics plays a very important role in an average Indian’ life. Right from our birth and our entire primary and secondary education a child has to go through tortures of the tyrannical Maths.


Every Indian parent wants his or her child to excel in maths than other subjects. A child scoring hundred per cent in maths is considered to be brilliant and those flunking it are seen with awe of sympathy. What is with us Indian and Maths?


Well our possessiveness and demand for excelling in maths may be because we feel proud of our Indian History that gave so much to the world of Mathematics. We were the one giving Zero to the world. It was Aryabhata the great Indian  mathematician and Astronomer  who first thought of it.


S. Ramanujan whose 125th birthday was recently celebrated by the University of Florida was a great Indian mathematician who just enjoyed maths. He loved it so much that in his childhood he uses to fail in every subject, because he gave all the time to his beloved maths.


Shakuntla Devi, a world renowned mathematician who is being also called as the Human computer and is having a Guinness world record for lightest calculations. In 1977, she could calculate 23rd root of 201 digit number in just 50 sec. JUST 50 SECONDS. Whereas we might take 10 min to calculate cubic root of 5 digits.  In 1980, she multiplied two 13 digits number randomly given to her by the computer department of imperial college, London. her puzzles are still being used by various recruiters to test their applicant's IQ level.


It’s sad to inform you all that Shakuntla Devi passed away this April, because of her respiratory ailments in Bengaluru. It’s even sadder to know that her tricks died with her as schools had refused to teach her ways. Had it not being the case, Indian would not have to use calculators.


Here is a video of her powers


Keep Looking …

Sunday, April 21, 2013

Logical Addressing & IP Addressing


Logical addressing is a function of the network layer of the OSI model. Unlike  hardware address( MAC ADDRESS) it provides a hierarchical structure to separate networks. A logical address identifies not only  a unique HOST ID , but also the network  that host belongs to . These are not hard-coded onto hosts and can be freely changed.

Two most common protocols used are IPX (INTERNETWORK PACKET EXCHANGE) and IP( INTERNET PROTOCOL).IPX was predominantly used on novell  networks,but is mostly deprecated. 

Nowadays IP is mostly used and their are already two versions of IP in the market.these are as follow
  1. IPv4 (32- bits)
  2. IPv6 (128-bits)
IP was developed by the department of Defence(DoD) during 1970's.it was included in a group of protocols that became to be known as TCP/IP suite.


 WHY WE REQUIRE IP ADDRESS?


IP addressing is just similar to the addressing of your home. Just as when we need a post from an outside city we require a Source address and a Destination address on the envelop , in the same way when packets are routed in Layer 3, they require address which are unique throughout the network.

NOTE- unlike MAC address ,  these are unique throughout the world and not just the network in which they are.

Each ip address has its subnet mask  which is decoded into bcd format which represent the actual ip address of network as well as the host
Things related to an IP address
  1. HOST ID
  2. NETWORK ID
  3. NETWORK ADDRESS
  4. SUBNETTING/SUPERNETTING
  5. BROADCAST ID
  Firstly , lets understand how does an IP address ( version 4) looks like
                                               
                                                          xxx.xxx.xxx.xxx

The above example is also called as decimal notation because of the periods used in representing it . here each block consist of 8 bits hence the range 0- 255 is available for each block. As a result  the total available permutations are  232 

But even this is getting over and hence we have to introduce ip version 6 which has more address space available and more security implementations.

Their are mainly 5 class through which we differentiate IPv4 address.These are as follow .

  1. Class A                               ( 0-126)
  2. Class B                               (128-191)
  3. Class C                               (192-223)
  4. Class D                               (224-239)
  5. Class E                               (240-254)


Note that range give beside them denotes the range of only 1st block of IPv4. IP address 
 127.0.0.0  has been reserved for  research purpose and is also called as the Loop back IP . This address has been used a lot by the crackers who try to avoid the auto updation of their pirated software suits whereas students sometime use it to play pranks on their mates.

Keep Looking...

Saturday, April 20, 2013

Internetwork Operating System IOS

Router Theoretical Image 

IOS is Cisco's internetwork operating system. Just as PCs have operating systems and LANs have network operating systems, it is Cisco's belief that internetwork need their own operating systems. Cisco's goal was to create an operating system that could evolve as the network evolved.Cisco IOS is a multitasking operating system that is integrated with routing, switching, internetworking, and telecommunications functions.

It is a CLOSED SOURCE model that works only on CISCO devices. It's a command line interface hence can be  difficult to those who love to work on gui.though i personally never had any problem in working as the commands are easy to remember and execute. the Current version of IOS is 15.2(4)M2

Now as the IOS is present on the devices ,they can be as accessed by connecting a terminal or PC to a console port on a networking device. A terminal emulation package or Telnet is used to access the IOS software.

NAMING CONVENTION OF IOS FILES

Whenever " show flash " command is executed on privilege Mode you will find something like this
c2600-ik9s-mz.121-3.T.bin
  • c2600 --- denotes the CISCO hardware
  • ik9s-- feature supported
  • m- indicates the memory location
  • z-- show the compression technique used
  • 121--Maintenance release
  • 3-- individual release
  • T-- train Identifier
DIFFERENT TYPES OF FLASH MEMORY LOCATIONS
   
Code                Location
FIN FLASH
MIN RAM
RIN ROM
LLOCATED AT RUN TIME

DIFFERENT TYPES OF COMPRESSION


CODECOMPRESSION
ZIN ZIP
XIN MZIP
WIN STAC COMPRESSION

All the information left, will be discussed in detail in the future Blogs..
Till then bye

keep Looking...

Friday, April 19, 2013

High Density Resolution Imaging ( HDR) , Now in cell phones also


Yesterday, my friend bought a cell phone , which had this amazing feature of HDR mode in camera. HDR is high density resolution imaging hence acronym HDRI or HDR. This radical technology is used to capture images with high variation of contrast, brighter and darker sections in the same photo. The desire for such mechanism has been long recognized .Even CS2 introduce the merge to HDR function in 2005. With this technique now even a novice photographer can take  life like pictures without even turning the exposure setting . If you feel like having softwares to do that , you can some in net .Like 


are two such stand alone softwares but they might not be free and u will have to pay for them.

 In normal mode, camera takes only one image at a particular aperture mode, so it might lose the detailing of the darker and brighter section. IN HDR mode, the camera takes multiple images of different exposure levels. Then combine them together maintaining more details of the scene and making it more real like. The main goal is to make electronic picture have more color range and dynamic as our human eye see them. The HDRi data format is a 64bit (color) or 32bit (greyscale) data format for saving RAW data of HDR scans, hence the quality.

The picture below is taken inside a shop with glass windows , with a cell phone . Due to sunshine when picture is taken without HDR mode, it appears picture 1. But when the same image is taken with HDR mode, see the difference in it. You can see through the glass (cars and some people).

Picture 1 without HDR Technique



Picture 2 with HDR Technique


 It works well for the pictures where a source of light is between you and your picture .Like while capturing skyline or horizon. It’s great to see cell phone manufactures taking camera quality in their phones to next level.

Keep Looking …

Thursday, April 18, 2013

Yet again , CGL 2013 Dates are changed


EMQFUJF6FYBZ

Yet , another time  Staff Selection Commission of India Changed its CGL 2013 paper from 28th April to 19th May.CGl 2013 paper was to be conducted in 2 phase - one on 14 and another on 21. Due Dr. Bhimrao Ambedkar Jayanti on 14, the paper was postponed to 28 May 2013.


But after considering the plea of thousands of candidates who were appearing for SBI PO on the same date ( 28th) and lack of venues . The paper is again postpone to 19 may this time. This clearly shows the mismanagement of ssc . The paper on 21 April , will remain unaffected and will be conducted accordingly . 


On 19 May , JEE mains was to be conducted , which has been now shifted to 9 June. This date is very near to IAS pre papers to be conducted on 25th May , which might cause some hazels for some students. Best of luck to all the students and see to it that dates should not change any further.


 For official Statements look  for this site 


Hope SCC next time plans his events while keeping in views the Gazetted holidays and save us this commotion. 

Keep Looking...

Wednesday, April 17, 2013

Eco feminism and Piplantri


Eco feminism, I came across the word while I going through an article in THE HINDU  and thought of sharing the  piece with you all, in my words . Piplantri a village or guan in Rajasthan (arid region of India) has done a remarkable job in establishing Eco feminism. 

For village, Rajasthan which has poor child sex ratio, to promote Eco feminism is itself appreciable. In this village when were a girl child is born they plant 111 trees   and  amount Rs 31,000 or say $620 is given to their parents  ,with an agreement that this will be given to their daughter after she attains 18 years of age. It’s not only increasing the number of trees in the desert area of Rajasthan but also improving the sex ratio, eradicating the female foeticide.


Till now around quarter million trees have been planted .This is all due to the pressing attitude of the village head, Sarpanch who lost his loving daughter. These people are not only planting trees, but also taking care of them. They have planted around two million + aloe Vera shrubs, to prevent the termite attack on the trees.


If one village can do it why can't all of us. Just think , if even half of us get inspired and another half follow it , earth would be a much greener and better place to live. This is also improving the social structure of the area as the number of girls are increasing ( I am being biased by assuming that women are better , those who don't agree with me just ignore it ). 


Keep Looking

Tuesday, April 16, 2013

WHY DO WE TWIST THE CABLE IN CROSSOVER ?


WHY DO WE TWIST THE CABLE IN CROSSOVER ?

The  primary means of reducing crosstalk--the term crosstalk came from the ability to (overhear conversations on other lines on your phone--between the pairs in the cable, is the double helix configuration produced by twisting the wires together. This configuration produces symmetrical (identical) noise signals in each wire. Ideally, their difference, as detected at the receiver, is zero. In actuality it is much reduced.

Two wire color-code standards apply: EIA/TIA 568A and EIA/TIA 568B . The codes are commonly depicted with RJ-45 jacks as follows (the view is from the front of the jacks):
STANDARD RJ -45
Note that pins 4, 5, 7, and 8 and the blue and brown pairs are not used in either standard. Quite contrary to what you may read elsewhere, these pins and wires are not used or required to implement 100BASE-TX duplexing--they are just plain wasted.

Another way of remembering the color coding is to simply switch the Green set of wires in place with the Orange set of wires. Specifically, switch the solid Green (G) with the solid Orange, and switch the green/white with the orange/white.
that's it for now....

Keep Looking...

Boston Marathon ended with a blast !! Another Attack On American Soil


Boston Attack ,
Picture taken from google no copyright infringement intended
16 Apr 2013, when the participants of Boston Marathon , world oldest marathon,  were reaching the finish line , 2 bombs exploded with 30 sec difference and nearly 70 yards apart from each other .after  9/11 , this is the single biggest attack on American people in their homeland.people all  around the world and Americans themselves are not clear what had happened and how did it happen though American have enforced stringent rules and security after 9/11.


After the incident FBI reported it to be a terrorist attack , but later changed their statement of reviewing the situation first .American president Mr. Barack Obama while addressing to the people of America said 


"Make no mistake we will get to the bottom of this and we will find out who did this and we will find out why they did this. Any responsible groups will feel the full weight of justice.
The American people will say a prayer for Boston tonight and Michelle and I send our prayers to the families of the victims in the wake of this senseless loss.”

Its is reported that 3 people died and nearly 100 people suffered injuries in these explosion .The investigation  has started and people have been questioned about the incident .A Saudi national has been suspected , but nothing can be said confirmative .

According to  The New York Post

"Investigators have a suspect — a Saudi Arabian national — in the horrific Boston Marathon bombings, The Post has learned.Law enforcement sources said the 20-year-old suspect was under guard at an undisclosed Boston hospital.It was not immediately clear why the man was hospitalized and whether he was injured in the attack or in his apprehension.
The man was caught less than two hours after the 2:50 p.m. bombing on the finish line of the race, in the heart of Boston."








World Heritage Day, 18th April


18th april , a day to remember the glories and the architecture of our ancestors . Heritage around the world serves as a lesson to us ,they let us know about the culture , society and people of that time. They teach us what to do and what not to do . World heritage are not just monuments or old building, they can be anything from books to dance, from letters to poem . Even our culture and traditions are heritage to us.The World Heritage List includes 962 properties till now .


Over a period  UNESCO has considered 29 such world heritage sites in India .These have 23 cultural  and 6 natural  site spread across the nation . Few of them are the
Agra Fort


  1. Agra Fort (1983)
  2. Ajanta Caves (1983)
  3. Buddhist Monuments at Sanchi (1989)
  4. Champaner-Pavagadh Archaeological Park (2004)
  5. Chhatrapati Shivaji Terminus (formerly Victoria Terminus) (2004)
  6. Churches and Convents of Goa (1986)
  7. Elephanta Caves (1987)
  8. Ellora Caves (1983)
  9. Fatehpur Sikri (1986)
  10. Great Living Chola Temples (1987)
  11. Group of Monuments at Hampi (1986)
  12. Group of Monuments at Mahabalipuram (1984)
  13. Group of Monuments at Pattadakal (1987)
  14. Humayun's Tomb, Delhi (1993)
  15. Khajuraho Group of Monuments (1986)
  16. Mahabodhi Temple Complex at Bodh Gaya (2002)
  17. Mountain Railways of India (1999)
  18. Qutb Minar and its Monuments, Delhi (1993)
  19. Red Fort Complex (2007)
  20. Rock Shelters of Bhimbetka (2003)
  21. Sun Temple, Konârak (1984)
  22. Taj Mahal (1983)
  23. The Jantar Mantar, Jaipur (2010)

Taj Mahal

khajuraho Temples













you can even use  the google  map for the same . Happy tourism . :)




                                                                   View Larger Map


keep looking ....






Monday, April 15, 2013

Color Coding Of Ethernet wires (CAT Cables )


Color coding of the ethernet wires ( CAT series) is one of the most important things and if configured incorrectly ,the connectivity will be  damaged . So be carefully before doing any experiment on your RJ45 connector wiring in home.

The image below is self explanatory.



Color Coding OF ethernet wires


Connecting Wires


Wires play an important role  connecting  as well as deciding  speed of the connection established.Networking Cables are used to connect one network device to another or to connect two or more computers to share printer, scanner etc. Different types of network cables like Coaxial cable, Optical fiber cable, Twisted Pair cables are used depending on the network's topology, protocol and size.
There are several types of wires , few of them will be discussed over here.
  • Twisted Pair--(also known as 10BaseT) is ideal for small, medium, or large networks that need flexibility and the capacity to expand as the number of network users grows. 10BaseT cabling looks very similar to that of common telephone cable.If it contains 4 wire then an RJ11(Registered jack) connector should be used and in case of  8 wires  RJ45 connector.In a twisted-pair network, computers are arranged in a star pattern as mentioned earlier. Each computer has a twisted-pair cable that runs to a centralized hub. Twisted-pair is generally more reliable than thin coax networks because the hub is capable of correcting data errors and improving the network's overall transmission speed and reliability. Also known as up-linking, hubs can be chained together for even greater expansion.
RJ 45
  • Straight-through cables are used for connecting computers to a hub.
  • An Ethernet crossover cable is a type of Ethernet cable used to connect computing devices together directly where they would normally be connected via a network switch, hub or router.Crossed cables are used for connecting a hub to another hub (the exception to this is when some hubs have the built-in up link   port that is crossed internally, which allows you to uplink hubs together using a straight cable).
  • A patch cable is an electrical or optical cable, used to connect one electronic or optical device to another for signal routing. Devices of different types  are connected with patch cords, and it works. It is a very fast connection speed. Patch cords are usually produced in many different colors so as to be easily distinguishable.
The Color Coding of these Ethernet crossover cables is in the next blog, till then ...


Keep looking..

Sunday, April 14, 2013

Elephanta cave , Incredible India

Elephanta caves , Mumbai , India

The photo on the left is from my personal scrapbook . I took it ,in 2010-11 when i went to on a leisure trip to Mumbai .


This caves are situated on an island , 10 kilometer east of Mumbai. It had a huge statue of Elephant at the entrance and so it gets its name . It was a place of worship for Hindu , until Portuguese came in 16th century


The rock cut architecture of the caves has been dated to between the 5th and 8th centuries, although the identity of the original builders is still a subject of debate. The caves are built from solid basalt rock. All the caves were also originally painted in the past, but now only traces remain. 


There are a total of 4 caves and are still under renovation by the archaeological department of India.Though the 1st and 2nd  caves are fascinating to watch , the rest are not clear and deteriorated  . You might not be allowed to enter them also . But never the less , its a good trip to the island through a ferry which might take $3- $4 .Its one of the places you should go if you come to Mumbai , but if you cannot bear humidity then i would suggest you to skip it.

Saturday, April 13, 2013

IBPS SO 2013 Expected Cut-Offs


With thousands waiting for the results to be out later i this week , many are worried about the cut off of each section in SO paper. As there were 4 section in the paper and one needs to clear the cut off of each , candidates are worried as till now no official statements has been released from IBPS side.


The SO paper consisted of 4 Sections 
  1. Quantitative                                          50 marks
  2. Reasoning                                            50 marks
  3. English                                                 50 marks
  4. P.K ( Professional Knowledge )          50 marks



According to the speculations , the cutoff this time is going to be same as that of Last year 2012 ,that would be  24/21 marks in each section for GEN/Others

Though this years paper was easier in respect of P.K section as they were mostly question asked in clerical examinations  while Reasoning section was a real trickster which took most of the time . Quantitative  and English were easy and one could have easily attempted around 30-35 questions .

Many blogger and analyst are also predicting a varying cut off for sections this year, around 35 in P.K and 24 in Reasoning .But i stand will my view that it will be same for each section as previous year.

Gold Plunges In deep

Nearly after 3 years after The great recession, gold prices drops down 5%  to $1487 per ounce ( a drop by 78 ounce ).

 In India , it came down to 28350 per 10 grams  in open market and even below 28000 in    Mcx - India's first multi commodity exchange.

The fall has been a great shock to people who have been investing in gold as it was providing around 20 % returns on their investments . Experts state that , the fall is because of the strengthening of USA's economy . Due to which people have shifted their interest to US security bonds instead of gold. As a result the drop in the price .

The price of gold may drop a little further , as European countries laden with loan - crisis are thinking of selling their gold reserves(rumours) .It is expected that gold would bottom out at roughly $1,281 per ounce. If this happens , people hoarding gold will have to clear their safes and think of something else to invest.


The fall , is gold sign for Indian govt , present crisis about the CAD ( Current Account Deficit ) and has to pay for huge gold imports . It is expected that gold will fall down to 25000 per 10 gram till the end of the this month. SO for common Indian buyer , its a good time to go for a jewelry shopping.

TCP/IP MODEL


The TCP/IP model is a description framework for computer network protocols created in the 1970s by DARPA, an agency of the United States Department of Defense.TCP/IP is the short form of  transmission control protocol and Internet protocol.
Tcp/ip is the basic communication language or protocol of the Internet, nowadays. It can also be used as a communications protocol in a private network (either an intranet or an extranet, VPN). When you  access  Internet, your computer is provided with a copy of the TCP/IP program just as every other computer that you may send messages to or get information from also has a copy of TCP/IP. The TCP/IP Model is just another model ,which replaced OSI (because of various drawbacks and lack of protocols).
There are 4 layers of TCP/IP , which are divided into two groups.
  1. Transmission protocol- It the   higher layer, that  manages the assembling of a message or file into smaller packets that are transmitted over the Internet and received by a TCP layer that reassembles the packets into the original message.
  2. Internet protocol -Its the lower layer, that  handles the address part of each packet so that it gets to the right destination.
The following shows the different layers of TCP/IP  Model

Friday, April 12, 2013

OSI Layers


In the last blog , we saw what the OSI Layers .Now its time to see what each layer is ,in short

A) Application Layer-It is employed in software packages which implement client-server software. When an application on one computer starts communicating with another computer, then the Application layer is used.

B) Presentation Layer-This provides function call exchange between host operating systems and software layers. Mostly dealing with compression ,encryption and decryption

C) Session Layer-The Session layer defines how data conversations are started, controlled and finished. It allows to create dialog between the systems  .

D) Transport Layer -  Ordering and reassembling of packets that may have been broken up to travel across certain media. It guaranties that the packet reached the destination successfully.

E) Network Layer- Mostly, the routing of packets is done here. Responsible for the delivery of packets end to end and implements a logical addressing scheme to help accomplish this.

F) Data Link Layer - Its divides the packet into frames and provide error correction by adding a trailer bit to the frame.

G) Physical Layer--This layer deals with the physical aspects of the media being used to transmit the data. Deals with the conversion of data bits into electric signals , their transmission and synchronization .

This can be easily memorized by 
" ALL PEOPLE SEEMS TO NEED DATA PROCESSING"

hope u understood and Best of Luck.

keep looking....

OSI Model Of Networking


OSI, Open Systems Interconnection model ,is open standard for communication among two systems. OSI model was developed  " Charles Bachman " which evolved to remove various difficulty faced in ARPANET. If you are interested ,the actual document is available free of cost at
TU-T/X.200-series of recommendations 

or

 http://www.itu.int/rec/T-REC-X.Imp200-200612-I/en


The Open System Interconnection (OSI) model is a set of protocols that attempt to define and standardize the data communications process. Its divides the communication channel into 7 layers ,each layer performing its own functionality. Numerous protocols at each layer provide security and encapsulation . each layer is at the top of another and transfer data to each other from SAP ( service access protocol)
The figure below show us the 7 layers of OSI
As in the figure the last three layers are  grouped as "Media  layers" and the upper four as "Host Layers". Media layers are  mainly responsible for transferring the data through the physical medium ( converting the data into bit streams , synchronizing it, etc) where as the host layer is mainly focused on how the data is to be represented  and various applications interfaces.
NOTE:  Segment and Presentation Layers are usually not very useful and hence were removed in TCP/IP MODEl. 



hope u understood and Best of Luck.

keep looking....



CGL dates changed from 14 April to 28th April

Candidates preparing for CGL 2013, received a disappointing news on 12th April that the paper scheduled on 14th April 2013 was postponed to 28th April 2013. Officials published a statement on SSC 's official website about the delay . The delay is due to holiday on account of Dr. B.R. Ambedkar's birthday .

This has left many students puzzled as they have already downloaded the admit cards and many have even booked train for the same. Around 2 .5 lakh people  giving paper on this Sunday were left puzzled .
the statement of govt published was as follow:


"The Combined Graduate Level Examination, 2013 is scheduled to be held on 14th April, 2013 and 21st April, 2013. As 14th April, 2013 has been declared as closed holiday on account of the Birthday of Dr. B.R. Ambedkar, the examination scheduled on 14.04.2013 has been postponed and will now be held on 28.04.2013. Revised Admission Certificates may be downloaded from the website of the concerned Regional Offices of Staff Selection Commission on or after 21st April,2013."



There might be a re-change in the date  as on 28th April , SBI was conducting its PO examination across the nation. Now the question is what will have happen to the candidates how have applied for both and if the dates do not change . 

Hoping the best for both .

Network Interface Controller/Card (NIC)


NIC or network interface card or network adapter, LAN adapter is an important  hardware requirement for connectivity . Actually this interface  card provides us the 'gateway' through which data from one computer A can be transfered to another computer B. Its somewhat the  same as normal gate that we use in daily life to enter and exit.
A NIC technically is network adapter hardware in the form factor of an add-in card such as a PCI or PCMCIA card. Its actually a stick( looking somewhat like ram) and is mostly having an RJ45 connector at their one end.( u can see it at the back of ur laptop or PC..its where ur Ethernet wire is attached). Here is an image of what NIC looks like:


NIC is OSI layer 2 device (DATA LINK LAYER U can see this for more osi blog) . its consist of factory fitted 48bit address similar to that of ip address, here its called the MAC address or the Media Access Control address which is in .human-friendly form, is represented in  six groups of two hexadecimal digits, separated by hyphens (-)  or  colons (:), in transmission order.
For example ,consider the following
  • 01-23-45-67-89-ab
  •  01:23:45:67:89:ab
  •  0001.4202.8360
the last one is not used much now days.

Basics Of Networking



Hey guys, this is the first time i m blogging and would like to start by talking about networking. What is  networking ,what u require for networking and few interesting  facts about  it...
So lets begin.

What is networking ??

In the world of computers, networking is the practice of linking two or more computing devices together for the purpose of sharing data. Networks are built with a mix of computer hardware and computer software.In easy words , what we are trying to do is that we want computer A to send a file to computer B ,so that i can be view over there.But we can use storage devices for this purpose.But what if  A is in C.A and B in Delhi. Its for this we need a system through which we can send the data while  maintaining its integrity ,authenticity and prevent manipulation  ..
Hardware  requirements are as follow :-
  • computer /laptops ( at least two of them)
  • NIC ( network interface card)
  •  Connecting wires( a large variety is available)
  • IOS (Internetwork Operating System)
  • Topology used to connect the systems
  • ID numbers,that identify two systems( usually called ipv4 ,ipv6)
Another important question 

Why do we require networking?? 

The answer is very interesting.
  1. sharing of info/data  that is required while working on the a project
  2. individual software cost is higher than that of  network softwares
  3. reducing the number of hardware ( using  a single printer /fax for, say, 100 computers)
  4. this is one of the most basic reason why students like us think of networking..( actually even i started it because of it)..Its Gaming ...
In the next blog i will tell u  about NIC and Connecting wires, i will also be telling about  the OSI Model and few other things...


Keep looking ..
Protected by Copyscape Duplicate Content Protection Tool