How does MP3 player works?

You see them here, there, everywhere! But have you ever really wondered at the technology behind that wonderful music playing contraption? Learn the technology behind one of the most popular gadgets around.

MP3 players use solid state memory, and are very similar to your computer's hard drive. In fact, some of them even double as portable hard drives! What solid state memory does is cut down on malfunctions as they contain no moving parts. They also help to avoid those annoying skips that are oh so prevalent in CD players. They use magnetic based storage, just like your hard drive and floppy drive. This does mean that they are susceptible to corruption by magnets and other devices that have a strong magnetic field (such as speakers or monitors)

The other parts of the MP3 player help to process the data on the drive and translate the 1s and 0s into audio signals. The player contains a microprocessor and controls the functions of the player.

The DSP (digital signal processing) chip is one that does a great deal of the work relating to the music. It is responsible for a few different functions, including loading the music from the drive, decompressing the mp3 (or other format), and convert the music into an analogue signal so that you can enjoy the latest hits. It then goes to the amplifier. This enhances the signal prior to sending it to headphones or speakers.

MP3 players draw their power from batteries, although some can switch to drawing power through a USB port when they have access to a computer. The typical MP3 player will allow you to listen to your music, make play lists, browse through your files, rearrange files, and delete files. As the technology gets more advanced, some also have expanded to let you watch movies, listen to local radio stations, and also store other types of files.

Contrary to the name, most MP3 players can handle a wide variety of music file formats. Format support can sometimes be added in at a later date by the manufacturer, who can issue a firmware update to be downloaded and installed on the player. As a last resort, enterprising people can make their own software, or reverse engineer the drive so that they know how to add the file format support themselves.

You can get music to put on your drive from a variety of sources. Be careful in making sure that your sources are legitimate, however. You wouldn't want to be on the receiving end of a RIAA lawsuit. You can also rip music from your personal CD collection. Most MP3 players come with software that can do this quickly and easily for you. In addition, there are loads of software download sites out there that have free CD to MP3 converters.

MP3 players are almost must have accessories, even for those not heavily into getting the newest gadgets and gizmos. With a capacity of hundreds or thousands of songs, do you really want to mess around with your CD player instead of this?

INFORMATION TO SLOVE ERRORS SHOWN BY DIFFERENT VIRUSES

*Windows cannot find SSVICHOSST.EXE make sure you typed name correctly and then try again to search for file, click the start button and then click start. For the solution log on to www.daniweb.com/blogs/entry1747.html

*Solution to virus occurred due to flash drives visit the following URL
www.pchell.com/support/aboutblank.shtml

*For deleting the viruses by name smss.exe , killer.exe visit the URL
http://infosecawareness.in and clean the registry affected by viruses.

*For viruses by name heurtrojangenericvirus and to access hidden files visit the URL http://malwareclawer.com/?=13

*Use less emails by name “YAMUNA” for solution visit the URL
http://www.cyberforensics.in/onlineemailtracer/index.asp then copy the email header and paste in above address then you will find a solution. To get the email header http://www.abika.com/reports/samples/emailheaderguide.html

*If the affected with viruses and cannot update then follow the below procedure
goto START -> RUN -> COMMAND -> REGEDIT Then type

hkey_local_machine\system\current control set\services then

hkey_local_machine\system\Microsoft\windowsNT\version then click viruses then update system.

*For viruses by the name ‘newfolder.exe’ these will affect your task manager and registry aditor and also disables them and creates new .exe folders and slows down system. For solution visit www.od3n.net/tools then click virus removal.

*If your internet explorer shows the message like “HACKED BY GODGILLA” it shows beside the address bar. To delete the above virus follow the following

steps

1. Download process explorer and run it. Delete or close the processes running in

your system by the name wscript.exe

2. Download RRT.exe file(remove restriction tool). By this we can enable the

disabled files.

3. Then START -> RUN -> REGEDIT Then type

hkey_current_user/software/Microsoft/windows/currentversion/run and delete

MS32DLL.

4. hkey_current_user/software/Microsoft/internetexplorer/main and delete

“windows title” i.e., “HACKED BY GODGILLA”.

5. Then goto “MY COMPUTER” FILE -> TOOLS -> FOLDER OPTIONS -> ADVANCE

SETTINGS Then check for “show hidden files and folders” and hide extension

for the known file types and hide protected “operating system files” on them.

Then click OK and restart the computer.

TIPS TO PROTECT YOUR SERVERS FROM HACKERS

Is your server secure?

To reply in a word, the answer is ‘No’. No machine connected to the Internet is 100% secure. This does not mean that you are totally helpless. You definitely can take measures to protect your machines from hackers, but you cannot avoid them completely. You can compare your system to a house — whenever windows and doors are open, then the probability of a thief getting in is high, but if the doors and windows are closed and locked the probability of being robbed is less, but still not nil!

What is Information Security?

For our purpose, Information Security means the methods we use to protect sensitive data from unauthorized users.

Why do we need Information Security?

The entire world is rapidly becoming IT enabled. Wherever you look, computer technology has revolutionized the way things operate. Some examples are airports, seaports, telecommunication sector and TV broadcasting, all of which are thriving as a result of the use of IT. "IT is everywhere."

A lot of sensitive information passes through the Internet, such as credit card data, mission critical server passwords and important files. There is always a chance of someone viewing and/or modifying the data while it is in transmission. There are countless horror stories of what happens when an outsider gets hold of someone's credit card or financial information. The transgressor can use it in any way he/she likes and could even destroy you and your business by taking or destroying all your assets. As we all know, "An ounce of prevention beats a pound of cure." So, in order to avoid such critical situations, it is advisable to have a good security policy and security implementation.

Security Framework

Figure 1 illustrates the framework needed to implement a functioning security implementation.



This framework shows the basic steps in the life cycle of securing a system. "Risk Analysis" deals with risks associated with the data in the server to be secured. "Business Requirements" is the study that deals with the actual requirements for conducting business. These two components cover the business aspects of security implementation.

The "Security Policy" covers eight specific areas of security implementation and is discussed in more detail in the forthcoming section on security policy. "Security Service, Mechanisms and Objects" is actually the implementation part of security. "Security Management, Monitoring, Detection and Response" is the operational face of security, where we cover the specifics of how to find a security breach, and what needs to be done if a breach is found.

Security Policy

The Security Policy is a document that addresses the following areas:

1. Authentication: This section deals with what methods are used to determine if a user is real or not, which users can or cannot access the system, the minimum length of password allowed, how long a user can be idle before he is logged out, etc.
2. Authorization: This area deals with classifying user levels and what each level is allowed to do on the system, which users can become root, etc.
3. Data Protection: Data protection deals with details like what data should be protected and who can access which levels of data on the system.
4. Internet Access: This area deals with the details of users having access to the Internet and what they can do there.
5. Internet Services: This section deals with what services on the server are accessible from the Internet and which are not.
6. Security Audit: This area addresses how audit and review of security related areas and processes will be carried out.
7. Incident Handling: This area addresses the steps and measures to be taken if there is any breach of security. It also covers the steps to find out the actual culprit and the methods to prevent future incidents.
8. Responsibilities: This part covers who will be contacted at any given stage of an incident and the responsibilities of the administrator(s) during and after the incident. It is a very important area, since the operation of the incident handling mechanism is dependent on it.

Types of Information Security

There are two types of security – Physical security/Host security and Network security. Each of these sections has three parts:

1. Protection: Slow down or stop intrusions or damage;
2. Detection: Alert someone if a breach (or attempted breach) of security occurs, and quantify and qualify what sort of damage occurred or would have occurred; and
3. Recovery: Re-secure the system or data after the breach or damage and, where possible, undo whatever damage occurred.

Host security/Physical security

Host security/Physical security means securing the server from unauthorized access. For that, we can password protect the box with such steps as setting up a bios password, placing the computer box in a locked room where only authorized users have access, applying OS security patches and checking logs on regular basis for any intrusion and attacks. In Host security, we check and correct the permissions on all OS related files.

Network security

Network security is one of the most important aspects of overall security. As I mentioned earlier, no machine connected to the internet is completely secure, so security administrators and server owners need to be alert, and make sure that they are informed of all new bugs and exploits that are discovered. Failure to keep up with these may leave you at the mercy of some script kiddy.

Which operating system is the most secure?
Every OS has its own pros and cons. There are ways to make Windows more secure but implementation is quite costly. Linux is stable and reasonably secure, but many companies perceive it as having little vendor support. In my opinion, the best OS for security purposes goes to FreeBSD, another free Unix-like OS, but not many people are aware of its existence.

Is a firewall the final solution to the Network Security problem?

No, a firewall is just part of the security implementation. Again, we will use the example of a house. In a house, all the windows and doors can be closed but if the lock on the front door of the house is so bad that someone can just put any key-like thing in and open it, then what is the use of the house being all closed up? Similarly, if we have a strong firewall policy, it will restrict unauthorized access. However, if the software running on the box is outdated or full of bugs, then crackers can use it to intrude into the server and gain access to the root. This shows that a firewall is not the final solution. A planned security implementation is the only real quality solution to this issue.

Security is a continuous process

Continuing security is an ongoing process. Security administrators can only conduct their work on the basis of alerts and bug fixes released up to the date of securing. So, in order to accommodate all of the fixes for the latest bugs, security work has to be performed on a regular basis.

Does security implementation create overhead and/or reduce performance?

Yes, security implementation creates a small amount of overhead, but it need not reduce overall performance drastically. In order to take care of such things, a well-done security implementation has an optimization section where the security administration gives priority to both performance and security. While securing any software, we should secure it in such a way that it provides maximum performance.

Security audits: What should be checked?

Security audit is a part of security implementation where we try to find out the vulnerabilities of the system and suggest actions to improve security. In a normal audit, the points below should be checked and a report with the results of that audit created.

1. Check intrusion detection: Use chkrootkit or rkhunter for this purpose.
2. Check for known bugs in the software installed on the server: the kernel, openssl, openssh, etc.
3. Scan all network ports and find out which ports are open. Report the ports that should not be open and what program is listening on them.
4. Check whether /tmp is secured.
5. Check for hidden processes.
6. Check for bad disk blocks in all partitions (This is just to make sure that the system is reasonably healthy).
7. Check for unsafe file permissions.
8. Check whether the kernel has a ptrace vulnerability.
9. Check the memory (another system health check).
10. Check if the server is an open e-mail relay.
11. Check if the partitions have enough free space.
12. Check the size of the log files. It is better that the log size remains in megabytes.

How to determine if you are being hacked?

To find out if your box has been compromised or not, follow the below-mentioned steps. These will be handy in most of situations.

Check your box to see if your performance has degraded or if your machine is being over-used.
For that, use the commands:
vmstat
Displays information about memory, CPU and disk.
Ex: bash# vmstat 1 4 (where 1 is delay and 4 is count).
mpstat
Displays statistics about CPU utilization. This will help us to see if the CPU is overworked or not.
Ex: bash# mpstat 1 4 (where 1 is delay and 4 is count).
iostat
This command displays statistics about the disk system. A few useful options include:
-d - Gives the device utilization report.
-k - Displays statistics in kilobytes per second.
Ex: bash# iostat -dk 1 4 (where 1 is delay and 4 is count).
sar
Displays overall system performance.

Check to see if your server has any hidden processes running
ps
Displays the status of all known processes.
lsof
Lists all open files. In Linux, everything is considered a file and as such it will be possible to see almost all of the activity on your system with this command.

Use intrusion detection tools

· rkHunter (http://www.rootkit.nl/); and
· chkrootkit (http://www.chkrootkit.org/).

Check your machine's uptime

If the uptime is less than it should be, it could mean that somebody else is utilizing the machine’s resources. Linux does not crash or reboot under normal conditions because it is a stable OS. If your machine has been rebooted, try to find out the actual reason behind it.

Determine what your unknown processes are and what they are doing
Use commands like the following to take apart unknown programs:

readelf
This command will display what the executable's program is performing.
ldd
This command will show the details of libraries used by an executable.
string
This command will display the strings in the binary.
strace
This command will display the system calls a program makes as it runs.

Hardening Methodology

1. Read all security related sites and keep up to date. This is one of the main things that a security administrator or server owner should do. Server owners should be made aware of security and its importance. Security training is an important part of an overall security package.
2. Create a good security policy. Conduct security audits on the basis of this policy.
3. Keep your OS updated by applying all patches.
4. Install a custom kernel with all unwanted services removed and patched with either grsecurity or openwall.
5. Disable all unwanted services and harden the services you leave running; change file and directory permissions so that security is tightened.
6. Install a firewall and create good rule sets.
7. Test and audit the server on a regular basis
8. Install an intrusion detection system, log monitor, all of the Apache security modules, bfd, faf and tmp monitor. Make your partitions secure.
9. Run a good backup system to recover data in case of an intrusion, crash or other destructive incident.
10. Install a log analyzer and check your logs for any suspicious entries.
11. Install scripts to send out mail or enable notifications when a security breach occurs.
12. After a security breach, try to find out how, when and through what the breach occurred. When you find a fix for it, document the details for future reference.

Summary

Now let us conclude by covering the main steps by which a hosting server can be secured.

1. Determine the business requirements and risk factors applicable to the system.
2. Devise a security policy with the above data in mind. Get the management's approval and signoff on this security policy.
3. On approval of the policy, conduct a security audit on any existing systems to determine current vulnerabilities and submit a report regarding this to the management.

The report should also cover the methods needed to improve existing security. Here is a quick checklist:
* Software vulnerabilities;
* Kernel upgrades and vulnerabilities;
* Check for any Trojans;
* Run chkrootkit;
* Check ports;
* Check for any hidden processes;
* Use audit tools to check the system;
* Check the logs;
* Check binaries and RPMS;
* Check for open email relays;
* Check for malicious cron entries;
* Check /dev /tmp /var directories;
* Check whether backups are maintained;
* Check for unwanted users, groups, etc. on the system;
* Check for and disable any unneeded services;
* Locate malicious scripts;
* Querylog in DNS;
* Check for suid scripts and nouser scripts;
* Check valid scripts in /tmp;
* Use intrusion detection tools;
* Check the system performance; and
*Check memory performance (run memtest).
4. Implement the security policy.
5. Correct all known existing software vulnerabilities either by applying patches or by upgrading the software.
6. Implement host security.
* Protect your systems with passwords;
* Check the file systems and set correct permissions and ownerships on all directories and files:

chmod -R 700 /etc/rc.d/init.d/*

Use rpm -Va to find out if an rpm has been modified;
* Apply security patches to vulnerable software (i.e. patch -p1 < style="color: rgb(255, 0, 0);">* Remove all unneeded ttys and console logins by removing the entry from /etc/securetty;
* Check system logs (e.g. /var/log/messages, /var/log/secure, etc.);
* Set a password on the boot loader (lilo and grub both support this); and
* Monitor the system (nagios or big brother).
7. Implement network security:
* Remove all unwanted users and groups;
* Use custom security scripts that will send out notifications when sshing as root or while creating a user with uid of 0, etc.;
* Require passwords with 16 characters (can be done by making changes in login.def);
* Disable unwanted services using tcpwrapper (unwanted services can also be disabled through xinet.d or xinetd.Conf);
* Set up an idle timeout, so that idle users will be logged out after a certain amount of time;
* Disable all console program access (e.g. rm –rf /etc/security/console.app/);
* Enable nospoof option in /etc/host.conf;
* Specify the order in which domain names should be resolved (e.g. order bind hosts);
* Lock the /etc/services file so that no one can modify it;
* Restrict direct root login (comment out the PermitRootLogin login option in sshd_config);
* Restrict su, so that only wheel group members are able to su (You can use pam or disable the permission of other for the su binary);
* Limit users resources (using pam, specify the limits for each user in /etc/security/limit.conf);
* Secure /tmp (mount /tmp with noexec,nodev,nosuid);
* Hide the server details. Remove /etc/issues and /etc/issues.net;
* Disable unwanted suid and sgid files (e.g. find -type -perm -04000 -o perm 02000)
Examples of these: gpasswd, wall, and traceroute;
* Using iptables, allow only pings from specific locations (for monitoring systems to work);
* Take preventive measures against DOS, "ping of death" attacks, etc.;
* Install a firewall (e.g. apf and iptables) and allow only ports to operate, which the box needs for its normal functions; block all other ports to prevent mischief (Links: http://rfxnetworks.com/ and http://yolinux.com/TUTORIALS/LinuxTutorialIptablesNetworkGateway.htm);
* Install intrusion detection (e.g. install tripwire or aide). Links: http://www.cs.tut.fi/rammer/aide.html and http://redhat.com/docs/manuals/linux/RHL-9-Manual/ref-guide/ch-tripwire.html;
* Install sxid to keep an eye on suid and sgid scripts (Link: http://linux.cudeso.be/linuxdoc/sxid.php);
* Restrict ssh to specific IP addresses and specific users (Key authentication using passphrase is recommended);
* Install logcheck to check the logs;
* Install tmpwatch to delete unused files from the /tmp directory;
* Install and set up portsentry and configure it to use iptables to block Ips;
* Install mod_security and mod_dosevasive to safeguard apache;
* Delete files with nouser and nogroup;
* Deleted unwanted files/folders in htdocs, disable directory indexing;
* Check for unwanted scripts in /root, /usr/local, /var/spool/mbox;
* Install BFD and FAF for additional security;
* Disable open email relaying; and
* Submit a status report to the management detailing all discovered vulnerabilities and fixes.

Testing phase

Use tools like nessus, nikto and nmap to perform a penetration test and see how well your server is secured. Also, do a stress test.

Security is of utmost importance to a server, compromising security is compromising the server itself. Hence, an understanding of the same is a prerequisite to server ownership and administration.

TOP 100 ENGG COLLEGES IN INDIA

RANK Name of Institute City

1 Indian Institute of Technology IIT Kanpur Kanpur

2 Indian Institute of Technology IIT Kharagpur Kharagpur

3 Indian Institute of Technology IIT Bombay Mumbai

4 Indian Institute of Technology IIT Madras Chennai

5 Indian Institute of Technology IIT Delhi Delhi

6 BITS Pilani Pilani

7 IIT Roorkee Roorkee

8 IT-BHU Varanasi

9 IIT-Guwahati Guwahati

10 College of Engg , Anna University Guindy

11 Jadavpur University , Faculty of Engg & Tech Calcutta

12 Indian School of Mines Dhanbad

13 NIT- National Institute of Technology Warangal

14 BIT, Mesra Ranchi

15 NIT- National Institute of Technology Trichy

16 Delhi College of Engineering New Delhi

17 Punjab Engineering College Chandigarh

18 NIT- National Institute of Technology Suratkal

19 Motilal Nehru National Inst. of Technology Allahabad

20 Thapar Inst of Engineering & Technology Patiala

21 Bengal Eng and Science University , Shibpur Howrah

22 MNIT Malviya National Institute of Technology Bhopal Bhopal

23 PSG College of Technology Coimbatore

24 IIIT - International Institute of Information Technology Hyderabad Hyderabad

25 Harcourt Butler Technological Institute (HBTI) Kanpur

26 Malviya National Institute of Technology Jaipur

27 VNIT - Visvesvaraya National Institute of Technology Nagpur Nagpur

28 NIT- National Institute of Technology Calicut

29 Dhirubhai Ambani IICT Gandhinagar

30 Osmania Univ. College of Engineering Hyderabad

31 College of Engineering , Andhra University Vishakhapatnam

32 Netaji Subhas Institute of Technology New Delhi

33 NIT- National Institute of Technology Kurukshetra

34 NIT- National Institute of Technology Rourkela

35 SVNIT Surat

36 Govt. College of Engineering Pune

37 Manipal Institute of Technology Manipal

38 JNTU Hyderabad

39 R.V. College of Engineering Bangalore

40 NIT- National Institute of Technology Jamshedpur

41 University Visvesvaraya College of Engg. Bangalore

42 VJTI Mumbai

43 Vellore Institute of Technology Vellore

44 Coimbatore Institute of Technology Coimbatore

45 SSN College of Engineering Chennai

46 IIIT Allahabad

47 College of Engineering Trivandrum

48 NIT Durgapur Durgapur

49 SIT Calcutta

50 Mumbai University Inst of Chemical Tech Mumbai

51 Sardar Patel College of Engineering Mumbai

52 P.E.S. Institute of Technology Bangalore

53 Maharashtra Institute of Technology (MIT) Pune

54 Amrita Institute of Technology & Science Coimbatore

55 National Institute of Engineering Mysore

56 B.M.S. College of Engineering Bangalore

57 Laxminarayan Institute Of Tech. Nagpur

58 Nirma Institute of Technology Ahmedabad

59 IIIT Pune

60 Amity School of Engineering Noida

61 JNTU Kakinada

62 S.J. College of Engineering Mysore

63 Chaitanya Bharathi Inst. of Technology Hyderabad

64 IIIT Bangalore

65 SRM Institute of Science and Technology Chennai

66 SASTRA Thanjavur

67 Bangalore Institute of Technology Bangalore

68 The Technological Inst. of Textile & Sciences Bhiwani

69 I I I T Gwalior

70 JNTU Anantpur

71 M.S. Ramaiah Institute of Technology Bangalore

72 Gitam Vishakhapatnam

73 NIT- National Institute of Technology Hamirpur

74 NIT- National Institute of Technology Jalandhar

75 SV University Engineering College Tirupati

76 NIT- National Institute of Technology Raipur

77 Vasavi College of Engineering Hyderabad

78 The ICFAI Inst of Science and Technology Hyderabad

79 IIT- National Institute of Technology Patna

80 Cummins Colleges of Engg of Women Pune

81 VIT Pune

82 Shri Ramdeo Baba K.N. Engineering College Nagpur

83 Muffakham Jah Engineering College Hyderabad

84 Karunya Institute of Technology Coimbatore

85 D.J. Sanghvi Mumbai

86 Sathyabhama Engineering College Chennai

87 Kongu Engineering College Erode

88 Mepco Schlek Engineering College Sivakasi

89 Guru Nanak Dev Engineering College Ludhiana

90 Hindustan Inst of Engineering Technology Chennai

91 SDM College of Engineering Dharwad

92 R.V.R. & J.C. College Of Engg Guntur

93 Jamia Millia Islamia, New Delhi New Delhi

94 K.L. College of Engineering Veddeswaram

95 Dharmsinh Desai Institute of Technology Nadiad

96 S.G.S. Institute of Technology & Science Indore

97 Jabalpur Engineering College Jabalpur

98 Sree Chitra Thirunal College of Engineering Trivandrum

99 G.H. Patel College of Engg & Technology Vallabh Vidyanagar

100 Kalinga Institute of Industrial Technology Bhubaneshwar

BASIC CONCEPTS OF COMPUTER

COMPUTER MEMORY IS MEASURED:
Computer understands only one language that is Binary language.Binary language is also called as machine level language.It is a combination of 0's and 1's. A zero o a one is referred as one character and computer measured in the given format.
1 character = 1 bit
4 bits = 1 nibble
8 bits = 1 byte
1024 bytes = 1 kilo byte
1024 KB = 1 Mega byte
1024 MB = 1 Giga byte
1024 GB = 1 Tara byte
Some important points:
1. Floppy size Capacity
31/2 1.44MB
51/2 360KB
81/2 640KB

2. Zip Drive:
A single zip drive has the capacity of 70 floppy's diskettes. A large amount of data can't hold by a floppy but a zip drive can hold it and it very easily and can transferable.

3. Network:
A Network may be defined as an interconnection of two or more computers, which are attached with communication media, for the purpose of sharing information and resources.
4. Evaluation of Internet:
In 1969, the U.S Department Of Defence (DOD) did an experiment with four computers as a network to share the information from various government departments. This experiment was called as "ARPANET". ARPANET stands for Advance Research Project Agency.This network fulfilled the needs.
Internet is a network of the networks that provides the people to access the information.This has made it possible to network more than 60 million computers linked world wide, connecting more than 1 billion user's world wide to share the information at any time.

More Important Abbreviations for CSIT:
0. VIRUS - Vital information resources under seige(slang).
1. RAM - Random access memory.
2. ALU - Arithemetic logic unit.
3. CPU - Central processing unit.
4. ROM - Read only memory.
5. DIMM - Dual inline memory module.
6. LAN - Local area network.
7. NIC - Network interface card.
8. VGA - Vedio graphic adaptor(array).
9. ATX - Advanced technology extended.
10. CMOS - Complementary metal oxide semiconductor.
11. ISA - Industry standard architecture.
12. PCI - Peripheral component interconnect.
13. AGP - Accelerated graphic port.
14.SMPS - Switch mode power supply.
15. IDE - Integrated development(drive) electronics.
16.BIOS - Basic input output software (or) Built in operating system.
17. POST - Power on self test.
18. Heat sink - referred as North Bridge.
19. MICR - Magnetic ink character reader.
20. OCR - Optical character reader.
21. BCR - Bar code reader.

INFORMATION TECHNOLOGY

Information Technology (IT), as defined by the Information Technology Association of America (ITAA), is "the study, design, development, implementation, support or management of computer-based information systems, particularly software applications and computer hardware." IT deals with the use of electronic computers and computer software to convert, store, protect, process, transmit, and securely retrieve information.

Today, the term information technology has ballooned to encompass many aspects of computing and technology, and the term is more recognizable than ever before. The information technology umbrella can be quite large, covering many fields. IT professionals perform a variety of duties that range from installing applications to designing complex computer networks and information databases. A few of the duties that IT professionals perform may include data management, networking, engineering computer hardware, database and software design, as well as the management and administration of entire systems. When computer and communications technologies are combined, the result is information technology, or "infotech". Information Technology (IT) is a general term that describes any technology that helps to produce, manipulate, store, communicate, and/or disseminate information. Presumably, when speaking of Information Technology (IT) as a whole, it is noted that the use of computers and information are associated.

ELECTRONIC SHOW ROOMS AROUND HYDERABAD

Tirumala Music Center , Begumpet , Secunderabad.
Category: Electronics/Appliances
Landmark: Next to Bottles & Chimney Pub
Tirumala Music Center popularly known as TMC offers an expansive range of consumer electronics...

e Zone , Banjara Hills, Hyderabad
Category: Electronics/Appliances
Landmark: At City Center
e Zone sells electronic appliances like washing machines, televisions, refrigerators and...

Bajaj Electronics , Punjagutta, Hyderabad
Category: Electronics/Appliances
Landmark: Next to Hyderabad Central
This showroom sells the entire range of consumer electronics like television sets, refrigerators...

Bose , Somajiguda, Hyderabad
Category: Electronics/Appliances
Landmark: Near Spencer Super Market
Bose is internationally-acclaimed for its speakers and music systems. The products...

PCH e Zone , Somajiguda, Hyderabad
Category: Electronics/Appliances
Landmark: Beside RTO Office
This store offers consumer electronics like televisions, washing machines and mobile phones...

Shah's Electronics , RP Road, Hyderabad
Category: Electronics/Appliances
Landmark: Opp Best Buy Electronics
This store houses an extensive range of electronic items and home appliances ranging from...

Sony World , Banjara Hills, Hyderabad
Category: Electronics/Appliances
Landmark: Next to Gymkhana Club
Sony World offers all Sony India products under one roof. These include Sony's latest range of...

JD Electronics , Abids , Koti.
Category: Electronics/Appliances
Landmark: Near NTR Estates
All top brands of consumer durables excluding Videocon and Whirlpool are available at JD...

Bajaj Electronics , Lakdi-Ka-Pul, Hyderabad
Category: Electronics/Appliances
Landmark: Near Telephone Bhavan
Bajaj Electronics has a good range of electronic items like home theatre systems...

Next , Begumpet , Secunderabad.
Category: Electronics/Appliances
Landmark: Opp Indian Airlines Cargo Office
Next showroom stocks a range of electronic appliances that includes washing machines,television...

Digital Shoppy , Somajiguda, Hyderabad
Category: Electronics/Appliances
Landmark: Near HP Service Centre
Digital Shoppy offers consumer electronics and home appliances through its stores in Andhra...

Onkyo , Ameerpet, Hyderabad
Category: Electronics/Appliances
Landmark: Opp Vijaya Diagnostics
This is a store exclusively for Onkyo products. Available here are home theatre systems…

Electric World , MG Road, Hyderabad
Category: Electronics/Appliances
Landmark: Opp Sundaram Motors
Lights for home or commercial establishments, chandeliers, switches, wires and sockets are all…

Godrej Life Space , Madhapur, Hyderabad
Category: Electronics/Appliances
Landmark: Opp Satyam
Godrej Life Space sells a wide range of furniture for home and office. Bed sets, dinner tables…

Samsung Digital Home , Banjara Hills, Hyderabad
Category: Electronics/Appliances
Landmark: Near Taj Banjara
This store stocks a variety of products from the house of Samsung. This includes refrigerators...

Godrej Life Space , Abids , Koti.
Category: Electronics/Appliances
Landmark: Beside Santhosh Sapna Theatre
Godrej Life Space sells a wide range of furniture for home and office. Bed sets, dinner tables…

Sony World , Malakpet, Hyderabad
Category: Electronics/Appliances
Landmark: Diagonally Opp Andhra Bank
This is a Sony showroom and therefore deals with products only from the said brand…

Best Buy , RP Road, Hyderabad
Category: Electronics/Appliances
Landmark: Near Bata Bus Stop
Televisions, washing machines, microwave ovens and DVD players are available at Best Buy…

Brand Galaxy , Malakpet, Hyderabad
Category: Electronics/Appliances
Landmark: Opp Yashoda Hospital
LG, Samsung, Sony and Onida are among the brands available at Brand Galaxy. The product…

Godrej Life Space , MG Road, Hyderabad
Category: Electronics/Appliances
Landmark: Near Chermas
Godrej Life Space sells a wide range of furniture for home and office. Bed sets, dinner tables…

Sona Systems , Himayatnagar, Hyderabad
Category: Electronics/Appliances
Landmark: Near Narayanaguda Flyover
This shop stocks only LG products. Refrigerators, flat panel display, color televisions, washing…

Sound & Vision , Somajiguda, Hyderabad
Category: Electronics/Appliances
Landmark: Opp Kalanikethan
As the name suggests, this store offers electronic products that cater to the audio and visual...

Kundan Stores , Himayatnagar, Hyderabad
Category: Electronics/Appliances
Landmark: Above Pure O Natural
Appliances required for kitchen needs are all available at Kundan Stores. Mixers, grinders…

Srishti Electronics , Abids, Hyderabad
Category: Electronics/Appliances
Landmark: Opp Abids Petrol Pump
Open from 11 AM to 9.30 PM on all days except Sundays, this store stocks electronic goods...

Sona Systems , Ameerpet, Hyderabad
Category: Electronics/Appliances
Landmark: Near Green Park Hotel
For electronic items like microwave ovens, refrigerators, washing machines and the like, Sona…

Anand Electronics , Dilsukhnagar , Hyderabad
Category: Electronics/Appliances,
Landmark: Near Rajadhani Theatre
Anand Electronics has a whole range of washing machines, flat panel televisions and home...

Electro Plaza , Malakpet , Hyderabad
Category: Electronics/Appliances
Landmark: Near Mamta Complex
Open from 10 AM to 10.30 PM on all days, Electro Plaza is a consumer electronics store…

Best Buy , Malakpet , Hyderabad
Category: Electronics/Appliances
Landmark: Diagonally Opp Andhra Bank
Televisions, washing machines, microwave ovens and DVD players are available at Best Buy...

Tirumala Music Center , Malakpet , Hyderabad
Category: Electronics/Appliances
Landmark: Near Yashoda Hospital
Tirumala Music Center popularly known as TMC offers an expansive range of consumer electronics…

Sri Surya , Malakpet , Hyderabad
Category: Electronics/Appliances
Landmark: At Sai Krupa Market
All kinds of electronic appliances like televisions, DVD players, refrigerators and more are...

Deepak Enterprises , Abids , Hyderabad
Category: Electronics/Appliances
Landmark: Near NTR Estates
This store deals in consumer electronics and home appliances like televisions, washing machines…

Anjali Electronics , Abids , Hyderabad
Category: Electronics/Appliances
Landmark: Near Lepakshi Furniture and Interiors
All kinds of electronic items ranging from refrigerators and water heaters to televisions and…

iStore , Banjara Hills , Hyderabad
Category: Electronics/Appliances
iStore offers Apple products like laptops, ipods, speaker systems, ear phones, accessories for Apple products...

Tirumala Music Center , Banjara Hills ,Hyderabad
Category: Electronics/Appliances
Landmark: At Lumbini Jewel Mall
Tirumala Music Center popularly known as TMC offers an expansive range of consumer electronics...

Pixetra , Banjara Hills , Hyderabad
Category: Electronics/Appliances
Landmark: At Ashoka Metropolitan Mall
Pixetra is a store meant for photography enthusiasts. Cameras and camera accessories from brands...

Reliance Digital , Banjara Hills , Hyderabad
Category: Electronics/Appliances
Landmark: Opp ICICI Bank
Reliance Digital is an electronics appliances store that houses refrigerators, washing...

Pro Fx , Somajiguda , Hyderabad
Category: Electronics/Appliances
Landmark: Opp Kalanikethan Wedding Mall
Pro Fx has a range of high-end audio solutions and home theatre systems. The showroom...

Dignity Electronics , RP Road , Hyderabad
Category: Electronics/Appliances
Landmark: Near Mehaboob College
They sell Refrigerators, Television sets, DVD Players, Home Theaters, Washing Machines from brands...

PCH Style , Jubilee Hills, Hyderabad
Category: Electronics/Appliances
Landmark: Opp Chiranjeevi Blood Bank
The store stocks electronics appliances like televisions, washing machines and mobile phones...

iiird i , Somajiguda , Hyderabad
Category: Electronics/Appliances
Landmark: Opp Kalanikethan Wedding Mall
iiird i has a whole range of branded digital cameras, handicams, SLR cameras, printers...

iiird i , Khairatabad , Hyderabad
Category: Electronics/Appliances
iird i has a whole range of branded digital cameras, handicams, SLR cameras, printers...

iiird i , Abids, Hyderabad
Category: Electronics/Appliances
Landmark: Opp Canara Bank
iiird i has a whole range of branded digital cameras, handicams, SLR cameras, printers...

iiird i , Banjara Hills, Hyderabad
Category: Electronics/Appliances
iiird i has a whole range of branded digital cameras, handicams, SLR cameras, printers...

iiird i , Banjara Hills, Hyderabad
Category: Electronics/Appliances
Landmark: At Ashoka Metropolitan Mall
iiird i has a whole range of branded digital cameras, handicams, SLR cameras, printers...

Casa , Gachibowli, Hyderabad
Category: Electronics/Appliances
Casa has a whole range of kitchen appliances like rice cookers, mixers, grinders, juicers...

INFO ON IP ADDRESS

I P Address
An IP address (Internet Protocol address) is a unique address that certain electronic devices currently use in order to identify and communicate with each other on a computer network utilizing the Internet Protocol standard (IP)—in simpler terms, a computer address. Any participating network device—including routers, switches, computers, infrastructure servers (e.g., NTP, DNS, DHCP, SNMP, etc.), printers, Internet fax machines, and some telephones—can have its own address that is unique within the scope of the specific network. Some IP addresses are intended to be unique within the scope of the global Internet, while others need to be unique only within the scope of an enterprise.The IP address acts as a locator for one IP device to find another and interact with it. It is not intended, however, to act as an identifier that always uniquely identifies a particular device. In current practice, an IP address is not always a unique identifier, due to technologies such as dynamic assignment and network address translation.IP addresses are managed and created by the Internet Assigned Numbers Authority (IANA). The IANA generally allocates super-blocks to Regional Internet Registries, who in turn allocate smaller blocks to Internet service providers and enterprises.
IP versions
The Internet Protocol(IP) has two versions currently in use (see IP version history for details). Each version has its own definition of an IP address. Because of its prevalence, "IP address" typically refers to those defined by IPv4.
An illustration of an IP address (version 4), in both dot-decimal notation and binary.

IP version 4 addresses

IPv4 only uses 32-bit (4-byte) addresses, which limits the address space to 4,294,967,296 (232) possible unique addresses. However, many are reserved for special purposes, such as private networks (~18 million addresses) or multicast addresses (~270 million addresses). This reduces the number of addresses that can be allocated as public Internet addresses, and as the number of addresses available is consumed, an IPv4 address shortage appears to be inevitable in the long run. This limitation has helped stimulate the push towards IPv6, which is currently in the early stages of deployment and is currently the only contender to replace IPv4.
IPv4 addresses are usually represented in dotted-decimal notation (four numbers, each ranging from 0 to 255, separated by dots, e.g. 147.132.42.18). Each range from 0 to 255 can be represented by 8 bits, and is therefore called an octet.

IPv4 address networks

Currently, three classes of networks are commonly used. These classes may be segregated by the number of octets used to identify a single network, and also by the range of numbers used by the first octet.
• Class A networks (the largest) are identified by the first octet, which ranges from 1 to 126.
• Class B networks are identified by the first two octets, the first of which ranges from 128 to 191.
• Class C networks (the smallest) are identified by the first three octets, the first of which ranges from 192 to 223. Some first-octet values have special meanings:
• First octet 127 represents the local computer, regardless of what network it is really in. This is useful when testing internal operations.
• First octet 224 and above are reserved for special purposes such as multicasting. Octets 0 and 255 are not acceptable values in some situations, but 0 can be used as the second and/or third octet (e.g. 10.2.0.100).
A class A network does not necessarily consist of 16 million machines on a single network, which would excessively burden most network technologies and their administrators. Instead, a large company is assigned a class A network, and segregates it further into smaller sub-nets using Classless Inter-Domain Routing. However, the class labels are still commonly used as broad descriptors.

IPv4 private addresses

Machines not connected to the outside world (e.g. factory machines that communicate with each other via TCP/IP) need not have globally-unique IP addresses. Three ranges of IPv4 addresses for private networks, one per class, were standardized by RFC 1918; these addresses will not be routed, and thus need not be coordinated with any IP address registrars.Each block is not necessarily one single network, although it is possible. Typically the network administrator will divide a block into subnets; for example, many home routers automatically use a default address range of 192.168.0.0 - 192.168.0.255 (192.168.0.0/24).IP version 6 addressesIPv6 is a new standard protocol intended to replace IPv4 for the Internet. Addresses are 128 bits (16 bytes) wide, which, even with a generous assignment of netblocks, will more than suffice for the foreseeable future. In theory, there would be exactly 2128, or about 3.403 × 1038 unique host interface addresses. Further, this large address space will be sparsely populated, which makes it possible to again encode more routing information into the addresses themselves.Example: 2001:0db8:85a3:08d3:1319:8a2e:0370:7334Writing for Technology Review in 2004, Simson Garfinkel wrote notes that there will exist "roughly 5,000 addresses for every square micrometer of the Earth's surface".[1] This enormous magnitude of available IP addresses will be sufficiently large for the indefinite future, even though mobile phones, cars and all types of personal devices are coming to rely on the Internet for everyday purposes.The above source, however, involves a common misperception about the IPv6 architecture. Its large address space is not intended to provide unique addresses for every possible point. Rather, the addressing architecture is such that it allows large blocks to be assigned for specific purposes and, where appropriate, aggregated for providing routing. With a large address space, there is not the need to have complex address conservation methods as used in classless inter-domain routing (CIDR).Windows Vista, Apple Computer's Mac OS X, and an increasing range of Linux distributions include native support for the protocol, but it is not yet widely deployed elsewhere.

IP version 6 private addresses

Just as there are addresses for private, or internal networks in IPv4 (one example being the 192.168.0.0 - 192.168.255.255 range), there are blocks of addresses set aside in IPv6 for private addresses. Addresses starting with FE80: are called link-local addresses and are routable only on your local link area. This means that if several hosts connect to each other through a hub or switch then they would communicate through their link-local IPv6 address.Early designs specified an address range used for "private" addressing, with prefix FEC0. These are called site-local addresses (SLA) and are routable within a particular site, analogously to IPv4 private addresses. Site-local addresses, however, have been deprecated by the IETF, since they create the same problem that does the existing IPv4 private address space (RFC 1918). With that private address space, when two sites need to communicate, they may have duplicate addresses that "combine". In the IPv6 architecture, the preferred method is to have unique addresses, in a range not routable on the Internet, issued to organizations (e.g., enterprises).The preferred alternative to site-local addresses are centrally assigned unique local unicast addresses (ULA). In current proposals, they will start with the prefix FC00.Neither ULA nor SLA nor link-local address ranges are routable over the internet

IP address subnetting

Both IPv4 and IPv6 addresses utilize subnetting, or dividing the IP address into two parts: the network address and the host address. By using a subnet mask, the computer can determine where to split the IP address.

Static and dynamic IP addresses

When a computer uses the same IP address every time it connects to the network, it is known as a Static IP address. In contrast, in situations when the computer's IP address changes frequently (such as when a user logs on to a network through dialup or through shared residential cable) it is called a Dynamic IP address

Method of assignation

Static IP addresses are manually assigned to a computer by an administrator. The exact procedure varies according to platform. This contrasts with dynamic IP addresses, which is assigned either randomly (by the computer itself, as in Zeroconf), or arbitrarily assigned by a server using Dynamic Host Configuration Protocol (DHCP). Even though IP addresses assigned using DHCP may stay the same for long periods of time, they can generally change. In some cases, a network administrator may implement dynamically assigned static IP addresses. In this case, a DHCP server is used, but it is specifically configured to always assign the same IP address to a particular computer, and never to assign that IP address to another computer. This allows static IP addresses to be configured in one place, without having to specifically configure each computer on the network in a different way.In the absence of both an administrator (to assign a static IP address) and a DHCP server, the operating system may still assign itself a dynamic IP address using Zeroconf. These IP addresses are known as link-local addresses. For IPv4, link-local addresses are in the 169.254.0.0/16 address range.

Uses of dynamic addressing

Dynamic IP Addresses are most frequently assigned on LANs and broadband networks by Dynamic Host Configuration Protocol (DHCP) servers. They are used because it avoids the administrative burden of assigning specific static addresses to each device on a network. It also allows many devices to share limited address space on a network if only some of them will be online at a particular time. In most current desktop operating systems, dynamic IP configuration is enabled by default so that a user does not need to manually enter any settings to connect to a network with a DHCP server. DHCP is not the only technology used to assigning dynamic IP addresses. Dialup and some broadband networks use dynamic address features of the Point-to-Point Protocol.

Uses of static addressing

Static addressing is essential in some infrastructure situations, such as finding the Domain Name Service directory host that will translate domain names to numbers (IP addresses). Static addresses are also convenient, but not absolutely necessary, to locate servers inside an enterprise. An address obtained from a DNS server comes with a time to live, or caching time, after which it should be looked up to confirm that it has not changed. Even static IP addresses do change as a result of network administration, however (RFC 2072)