Showing posts with label Technology. Show all posts

Monday, November 26, 2012

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Who is System Administartor?

System Administartor


A system administrator, IT systems administrator, systems administrator, or system admin is a person employed to maintain and operate a computer system and/or network. System administrators may be members of an information technology (IT) or Electronics and Communication Engineering department.

The duties of a system administrator are wide-ranging, and vary widely from one organization to another. System admins are usually charged with installing, supporting and maintaining servers or other computer systems, and planning for and responding to service outages and other problems. Other duties may include scripting or light programming, project management for systems-related projects, supervising or training computer operators, and being the consultant for computer problems beyond the knowledge of technical support staff. To perform his or her job well, a system administrator must demonstrate a blend of technical skills and responsibility.

Related Fields

Many organizations staff other jobs related to system administration. In a larger company, these may all be separate positions within a computer support or Information Services (IS) department. In a smaller group they may be shared by a few system admins, or even a single person.

Database Administration:- A database administrator (DBA) maintains a database system, and is responsible for the integrity of the data and the efficiency and performance of the system.

Network Administrator:- A network administrator maintains network infrastructure such as switches and routers, and diagnoses problems with these or with the behavior of network-attached computers.

System Security Administrator:- A security administrator is a specialist in computer and network security, including the administration of security devices such as firewalls, as well as consulting on general security measures.

Web Administrator:- A web administrator maintains web server services (such as Apache or IIS) that allow for internal or external access to web sites. Tasks include managing multiple sites, administering security, and configuring necessary components and software. Responsibilities may also include software change management.

Technical Support Staff:-Technical support staff respond to individual users' difficulties with computer systems, provide instructions and sometimes training, and diagnose and solve common problems.

System Operator Administrator:- A system operator performs routine maintenance and upkeep, such as changing backup tapes or replacing failed drives in a RAID. Such tasks usually require physical presence in the room with the computer; and while less skilled than system admin tasks require a similar level of trust, since the operator has access to possibly sensitive data.

Web Administrator:- A web administrator is the administrator of a mail server.

In some organizations, a person may begin as a member of technical support staff or a computer operator, then gain experience on the job to be promoted to a system admin position.



Training

Unlike many other professions, there is no single path to becoming a system administrator. Many system administrators have a degree in a related field: computer science, information technology, computer engineering, information system management, or even a trade school program. Other schools have offshoots of their Computer Science program specifically for system administration.

Some schools have started offering undergraduate degrees in System Administration. The first, Rochester Institute of Technology started in 1992. Others such as Rensselaer Polytechnic Institute, University of New Hampshire, Marist College, and Drexel University have more recently offered degrees in Information Technology. Symbiosis Institute of Computer Studies and Research (SICSR) in Pune, India offers Masters degree in Computers Applications with a specialization in System Administration. The University of South Carolina offers an Integrated Information Technology B.S. degree specializing in Microsoft product support.

One of the primary difficulties with teaching system administration as a formal university discipline, is that the industry and technology changes much faster than the typical textbook and coursework certification process. By the time a new textbook has spent years working through approvals and committees, the specific technology for which it is written may have changed significantly or become obsolete.

There is some private institute such as Jetking, IICM, A-set, IIJT which also offer diploma course in System Administration.

Generally, a prospective will be required to have some experience with the computer system he or she is expected to manage. In some cases, candidates are expected to possess industry certifications such as the Microsoft MCSA, MCSE, MCITP, Red Hat RHCE, Novell CNA, CNE, Cisco CCNA or CompTIA's A+ or Network+, Sun Certified SCNA, Linux Professional Institute among others.

Sometimes, almost exclusively in smaller sites, the role of system administrator may be given to a skilled user in addition to or in replacement of his or her duties. For instance, it is not unusual for a mathematics or computing teacher to serve as the system administrator of a secondary school.

Skills

Some of this section is from the Occupational Outlook Handbook, 2010-11 Edition, which is in the public domain as a work of the United States Government. The subject matter of system administration includes computer systems and the ways people use them in an organization. This entails a knowledge of operating systems and applications, as well as hardware and software troubleshooting, but also knowledge of the purposes for which people in the organization use the computers.

Perhaps the most important skill for a system administrator is problem solving -- frequently under various sorts of constraints and stress. The system admin is on call when a computer system goes down or malfunctions, and must be able to quickly and correctly diagnose what is wrong and how best to fix it. They may also need to have team work, communication and problem solving skills; as well as being able to install and configure hardware and software.

System administrators are not software engineers or developers. It is not usually within their duties to design or write new application software. However, system admins must understand the behavior of software in order to deploy it and to troubleshoot problems, and generally know several programming languages used for scripting or automation of routine tasks.

Particularly when dealing with Internet-facing or business-critical systems, a system admin must have a strong grasp of computer security. This includes not merely deploying software patches, but also preventing break-ins and other security problems with preventive measures. In some organizations, computer security administration is a separate role responsible for overall security and the upkeep of firewalls and intrusion detection systems, but all system admins are generally responsible for the security of computer systems.

Responsibilities of a System Administrator

A system administrator's responsibilities might include:

• Analyzing system logs and identifying potential issues with computer systems.

• Introducing and integrating new technologies into existing data center environments.

• Performing routine audits of systems and software.

• Performing backups.

• Applying operating system updates, patches, and configuration changes.

• Installing and configuring new hardware and software.

• Adding, removing, or updating user account information, resetting passwords, etc.

• Answering technical queries and dealing with often frustrated users.

• Responsibility for security.

• Responsibility for documenting the configuration of the system.

• Troubleshooting any reported problems.

• System performance tuning.

• Ensuring that the network infrastructure is up and running.

In larger organizations, some tasks listed above may be divided among different system administrators or members of different organizational groups. For example, a dedicated individual(s) may apply all system upgrades, a Quality Assurance (QA) team may perform testing and validation, and one or more technical writers may be responsible for all technical documentation written for a company.

In smaller organizations, the system administrator can also perform any number of duties elsewhere associated with other fields:

• Technical support

• Database administrator (DBA)

• Network administrator/analyst/specialist

• Application analyst

• Security administrator

• Programmer

System administrators, in larger organizations, tend not to be system architects, system engineers, or system designers. However, like many roles in this field, demarcations between system administration and other technical roles often are not well defined in smaller organizations. Even in larger organizations, senior system administrators often have skills in these other areas as a result of their working experience.

In smaller organizations, IT/computing specialties are less often discerned in detail, and the term system administrator is used in a rather generic way — they are the people who know how the computer systems work and can respond when something fails.

System Administrator Privileges

The term "system administrator" may also be used to describe a security privilege which is assigned to a user or users of a specific computer, server, network or other IT System.

The Administrator level of system access permits that user to gain access to, and perform high level configuration features of the system.

This user privilege level is more commonly referred to within a computer or IT system as "administrator" (without the epithet "system"). It may also be called superuser or root.

For example a computer may have a user named "Administrator" or "Root" which has a security level sufficient to install software, or give other users access to the system. Alternatively a user of a system may be assigned to an "Administrators" group, membership of which grants them the same privilege as the Administrator user. These users may be referred to as System Administrators, referring only to the system privilege level, rather than the job function.

For security reasons, the name of an Administrator user or Administrators security group is often changed locally so that it is less easy to guess, in order to reduce system vulnerability to access by hackers.



Friday, November 16, 2012

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Portronics iLume projector launched for Rs 39,900



Portronics iLume projector launched for Rs 39,900


Portronics has launched the iLume multimedia pocket projector. As per an official statement by the company, this LED-illuminated projector comes with built-in speakers, and requires no additional sound magnification device for home entertainment use. It is based on DLP technology by Texas Instruments.

iLume gives you ease of convenience and freedom from calling for technical help to install the projector every time that you wish to use it. If you can dream it, iLume can probably do it.


Portronics iLume projector launched for Rs 39,900

iLume weighs around 650 grams. It comes with a brightness of 400 Lumens. It can project an image more than 120 inches long on the wall with the projection distance ranging from 0.5m to 5m. It has a Resolution is 1280 X 800 pixels, and can support 1080p and 720p formats.

iLume provides a connectivity port to connect to devices: VGA/ HDMI port to connect to laptops and desktops; AV port to connect to set top boxes to view television; HDMI connector to connect tablets and smartphones; and USB connectivity to connect to USB drives and directly play multimedia content without the use of laptops. Additionally, it has a microSD card slot to help project content directly from a microSD card, or a camcorder, or a camera using an AV cable. As per the official statement by Portronics, the life of iLume LED Engine is more than 20,000 hrs.

Portronics’ new iLume projector has been priced at Rs 39,900. The Portronics iLume Projector is available across the country. The projector has no maintenance cost.

In February this year, Portronics announced the launch of the battery-powered POR 315 Pico projector. The palm-sized POR 315 Pico projector enables one to view content with an additional HDMI input, with a resolution supporting 1024 X 600 pixels.

Priced at Rs 23,000, the Portronics POR 315 Pico projector is available ex-stock across the country. It seems to have quite a few features packed under its miniscule body.


Read morehttp://www.unp.me/f140/portronics-ilume-projector-launched-for-rs-39-900-a-99857/#ixzz2CMXPoDBU

Friday, November 9, 2012

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Firewall (History)

History of Firewall:

There was no one particular biological father for firewall, lot of people are involved in developing firewall technology, William Cheswick and Steven Bellovin wrote a book on firewall at AT&T Bell Labs and they built packet filtering technology and circuit-level gateway. David Pensak named first for building successful commercial firewall and Nir Zuk says that he has developed the firewall technology which is used in all firewalls today.

The first firewalls were developed by the Digital Equipment Corporation (DEC) back in the late 1980s.
These early firewalls operated mainly on the first four layers of the Open System Inteconnection (OSI) model, intercepting traffic on the wire and inspecting the properties of every indivdual packet to determine if they matched a confirured set of rules (source and destination address and port numbers for example). These packets would then either be dropped or forwarded as appropriate.

This method of traffic inspection, while repid, was soon found to be unnecessarily resource intensive and led directly to the introduction of cirucuit-level firewalls, later known as "stateful" firewalls, pioneerd by Check Point Software Technologies.

Generations of Firewall:

First Generation of Firewall:-

The first paper published on Firewall Technology was in 1988, developed by DEC as filter system named Packet Filters.
In beginning firewalls are based on router which examines the destination address of received packets, when a packet is received the header of the packet is copied to the routers CPU and compare with the router rules based on filtering rules, if packet satisfies all the rules then the packet is forwarded or else it will be dropped and a message will be sent back to the system so that no more packets will be sent.
Second Generation of Firewall:-

Second Generation of firewall Technology was in 1989-1990. Janardhan Sharma, Dave Presetto, and Kshitij Nigam at AT&T Bell Laboratories from 1989-1990 had developed second generation firewall which is known as “Satefull Firewall”. This firewall will prevent from denial-of-service attacks.
 Third Generation of Firewall:-


Third Generation of Firewall Technology was in 1991 which is Application Layer Firewall. Marcus Ranum and Bill Cheswick explained third generation firewall which is known as application firewall, it is also known as proxy based firewall, which operates at application level and inspects the inflow and outflow traffic and blocks inappropriate contents like virus and so forth.

Subsquent Development:-


Bob Braden and Annette DeSchon in 1992 were found a product named “visas”.An Israeli company named “Check Point Software Technologies” in 1994 found a ready to use software knows as “FireWall-1”.Present “Internet Engineering Task Force” (IETF) which is working for managing firewalls.


Thursday, November 8, 2012

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Firewall (Basic Introduction)

What is Firewall?
Firewall is a system designed to prevent unauthorized access to or from a private network. Firewalls can be implemented in both hardware and software, or a combination of both. Firewall are frequently used to prevent unauthorized Internet users from accessing private networks connected to the Internet, especially intranets. All messages entering or leaving the intranet pass through the firewall, which examines each message and blocks those that do not meet the specified security criteria.
The job of a firewall is use filtering to prevent unauthorized data from entering the network and restricting the data that can be sent out.
Firewalls can be hardware devices, which are dedicated single-purpose computers that run proprietary software, or they can be software-only packages that are installed on a regular PC running on top of on operating system like Windows or UNIX. Hardware firewalls tend to be more expensive (since you’re buying both hardware and software) but also usually offer better performance. Firewalls use NAT or router software to get data to the appropriate internal computer after checking it to ensure that the filtering rules allow it to go through

Firewall Filtering

Firewalls can filter data at different levels (different layers of the OSI networking model). The most common filtering methods are:
  • Packet filtering, which works primarily at the network layer
  • Circuit filtering, which works at the transport layer
  • Application filtering, which works at the application layer
Packet filters examine the information in the IP packet headers of messages and make the decision as to whether the data is allowed in (or out) based on that information. Thus packet filtering allows you to designate specific IP addresses (or host or domain names) that will be specifically blocked or specifically allowed. Filters can also process information at the transport layer (TCP and UDP port numbers). Specific ports can be blocked or left open. Because particular services use specific ports (for example, POP 3 incoming email uses port 110), this allows you to prevent specific types of data from entering the network (in this case, incoming POP3 email). There are two types of filtering, static and dynamic. With dynamic filtering, the necessary ports are opened up only when a communication is actually taking place, rather than staying open all the time. As soon as the communication ends, the port is closed.

Friday, October 19, 2012

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Disable user access to IE proxy settings

Hello friends, Today we will going to learn how to disable user access to IE proxy settings. Proxy settings  are provide a interface between public to private network internet access. We will set security to access particular website or webpage.
Now we are going to disable the proxy setting to access by user. For this we are going to use group policy.
So are you ready for learn to disable user access to IE proxy settings follow the step given bellow..

Step 1:- Open the run command and type gpedit.msc and click ok


Step 2:- A wizard will open as show below click on User Configuration


 Step 3:-  Click on Administrative Templates





 Step 4:- Now click on Windows Components come under Administrative Templates



Step 5:- Now click on Internet Explorer



 Step 6:- Now in Internet Explorer click on Disable Changing proxy settings


 
Step 6:- Double click on Disable Changing proxy settings  a wizard will open as show below, click on Enabled





Step 7:- Click ok and close the group policy wizard and log off the system and again log in.

Now user can't change proxy on IE. Try it and do you have another method to block it then let me know. I'm waiting your comments.