Desktop support qua
- 1. List of Probable questions 1. What are the types of Operating System ? Real-time Operating System: It is a multitasking operating system that aims at executing real-time applications. Real-time operating systems often use specialized scheduling algorithms so that they can achieve a deterministic nature of behavior. The main object of real-time operating systems is their quick and predictable response to events. They either have an event-driven or a time-sharing design. An event-driven system switches between tasks based of their priorities while time-sharing operating systems switch tasks based on clock interrupts. Multi-user and Single-user Operating Systems: The operating systems of this type allow a multiple users to access a computer system concurrently. Time-sharing system can be classified as multi-user systems as they enable a multiple user access to a computer through the sharing of time. Single-user operating systems, as opposed to a multi-user operating system, are usable by a single user at a time. Being able to have multiple accounts on a Windows operating system does not make it a multi-user system. Rather, only the network administrator is the real user. But for a Unix-like operating system, it is possible for two users to login at a time and this capability of the OS makes it a multi-user operating system. Multi-tasking and Single-tasking Operating Systems: When a single program is allowed to run at a time, the system is grouped under a single-tasking system, while in case the operating system allows the execution of multiple tasks at one time, it is classified as a multi-tasking operating system. Multi-tasking can be of two types namely, pre-emptive or co-operative. In pre-emptive multitasking, the operating system slices the CPU time and dedicates one slot to each of the programs. Unix-like operating systems such as Solaris and Linux support pre-emptive multitasking. Cooperative multitasking is achieved by relying on each process to give time to the other processes in a defined manner. MS Windows prior to Windows 95 used to support cooperative multitasking. Distributed Operating System: An operating system that manages a group of independent computers and makes them appear to be a single computer is known as a distributed operating system. The development of networked computers that could be linked and communicate with each other, gave rise to distributed computing. Distributed computations are carried out on more than one machine. When computers in a group work in cooperation, they make a distributed system. Embedded System: The operating systems designed for being used in embedded computer systems are known as embedded operating systems. They are designed to operate on small machines like PDAs with less autonomy. They are able to operate with
- 2. a limited number of resources. They are very compact and extremely efficient by design. Windows CE, FreeBSD and Minix 3 are some examples of embedded operating systems. 2. Difference between FAT and NTFS. NTFS 1)allows access local to w2k w2k3 XP win NT4 with SP4 & later may get access for somefile. 2)Maximum size of partition is 2 Terabytes & more. 3)Maximum File size is upto 16TB. 4)File & folder Encryption is possible only in NTFS. FAT 32 1)Fat 32 Allows access to win 95 98 win millenium win2k xp on local partition. 2)Maximum size of partition is upto 2 TB. 3)Maximum File size is upto 4 GB. 4)File & folder Encryption is not possible. 3. Enhancements in Windows 2003 from Windows 2000 4. Enhancements in Windows 2003 from Windows NT 5. What is Active Directory ? An active directory is a directory structure used on Microsoft Windows based computers and servers to store information and data about networks and domains. It is primarily used for online information and was originally created in 1996. It was first used with Windows 2000. An active directory (sometimes referred to as an AD) does a variety of functions including the ability to provide information on objects, helps organize these objects for easy retrieval and access, allows access by end users and administrators and allows the administrator to set security up for the directory. 6. Types of Firewall Network-Level Firewalls The first generation of firewalls (c. 1988) worked at the network level by inspecting packet headers and filtering traffic based on the IP address of the source and the destination, the
- 3. port and the service. Some of these primeval security applications could also filter packets based on protocols, the domain name of the source and a few other attributes. Network-level firewalls are fast, and today you'll find them built into most network appliances, particularly routers. These firewalls, however, don't support sophisticated rule- based models. They don’t understand languages like HTML and XML, and they are capable of decoding SSL-encrypted packets to examine their content. As a result, they can’t validate user inputs or detect maliciously modified parameters in an URL request. This leaves your network vulnerable to a number of serious threats. Circuit-Level Firewalls These applications, which represent the second-generation of firewall technology, monitor TCP handshaking between packets to make sure a session is legitimate. Traffic is filtered based on specified session rules and may be restricted to recognized computers only. Circuit-level firewalls hide the network itself from the outside, which is useful for denying access to intruders. But they don't filter individual packets. Application-Level Firewalls Recently, application-level firewalls (sometimes called proxies) have been looking more deeply into the application data going through their filters. By considering the context of client requests and application responses, these firewalls attempt to enforce correct application behavior, block malicious activity and help organizations ensure the safety of sensitive information and systems. They can log user activity too. Application-level filtering may include protection against spam and viruses as well, and be able to block undesirable Web sites based on content rather than just their IP address. If that sounds too good to be true, it is. The downside to deep packet inspection is that the more closely a firewall examines network data flow, the longer it takes, and the heavier hit your network performance will sustain. This is why the highest-end security appliances include lots of RAM to speed packet processing. And of course you'll pay for the added chips. Stateful Multi-level Firewalls - SML vendors claim that their products deploy the best features of the other three firewall types. They filter packets at the network level and they recognize and process application-level data, but since they don't employ proxies, they deliver reasonably good performance in spite of the deep packet analysis. On the downside, they are not cheap, and they can be difficult to configure and administer. 7. Difference between Hardware and Software Firewall. Hardware Firewalls You can buy a hardware firewall as a stand-alone product, but more recently hardware firewalls are typically found in broadband routers, and should be considered an important part of your system and network set-up, especially for anyone on a broadband connection. Hardware firewalls can be effective with little or no configuration, and they can protect every machine on a local network. Most hardware firewalls will have a minimum of four
- 4. network ports to connect other computers, but for larger networks, business networking firewall solutions are available. A hardware firewall examines data packet to determine their source and destination. It compares this information to a set of predefined or user-created rules that determine whether the packet should be routed to its destination or blocked and dropped. A person with general computer knowledge can plug in a firewall, adjust a few settings and have it work. To ensure that your firewall is configured for optimal security and protect however, you should learn its specific features, how to use them, and how to test the firewall to make sure it's protecting your network. Not all firewalls are created equal, and it's important to read the manual and documentation. Additionally the manufacturer's Web site usually provides a knowledgebase or FAQ to help you get started. If the terminology is a too tech-oriented, you can also use the Webopedia search to help you get a better understanding of some of the computer terms you will encounter while setting up your hardware firewall. To test your hardware firewall security, you can purchase third-party test software or search the Internet for a free online-based firewall testing service. Firewall testing is an important part of maintenance to ensure your system is always configured for optimal protection. Software Firewalls Most people prefer a software firewall. You install a software firewall on individual computers (just like any software), and you can customize its function and protection features. A software firewall protects your computer from outside attempts to control or gain access your computer, and, depending on which firewall you choose, it could also provide protection against the most common Trojan programs or e-mail worms. Many software firewalls have user-defined controls for setting up safe file and printer sharing and to block unsafe applications from running on your system. Additionally, software firewalls may also incorporate privacy controls, Web filtering (i.e., making certain types of sites – adult content, gambling, shopping, for example -- inaccessible) and more. The downside to software firewalls is that they only protect the computer they are installed on, not a network, so each individual computer needs to have a software firewall installed on it. Like hardware firewalls, there is a vast number of software firewalls from which to choose. To get started you may wish to read reviews of software firewalls and search out the product Web site to glean some information first. Because your software firewall will always
- 5. be running on your computer, you should make note of the system resources it requires and any incompatibilities with your operating system. A good software firewall will run in the background on your system and use only a small amount of system resources. It's important to monitor a software firewall once installed and to download any updates available from the developer. The best way to protect your computer and network is to use both types of firewalls, as each offers different but much-needed security features and benefits. Updating your firewall and your operating system is essential to maintaining optimal protection, as is testing your firewall to ensure it is connected and working correctly. 8. Name the seven layers of OSI model. Layer 7:Application Layer Defines interface to user processes for communication and data transfer in network Provides standardized services such as virtual terminal, file and job transfer and operations Layer 6:Presentation Layer Masks the differences of data formats between dissimilar systems Specifies architecture-independent data transfer format Encodes and decodes data; Encrypts and decrypts data; Compresses and decompresses data Layer 5:Session Layer Manages user sessions and dialogues Controls establishment and termination of logic links between users Reports upper layer errors Layer 4:Transport Layer Manages end-to-end message delivery in network Provides reliable and sequential packet delivery through error recovery and flow control mechanisms Provides connectionless oriented packet delivery Layer 3:Network Layer Determines how data are transferred between network devices
- 6. Routes packets according to unique network device addresses Provides flow and congestion control to prevent network resource depletion Layer 2:Data Link Layer Defines procedures for operating the communication links Frames packets Detects and corrects packets transmit errors Layer 1:Physical Layer Defines physical means of sending data over network devices Interfaces between network medium and devices 9. How to enable Firewall in Windows XP. A. Click Start, Control Panel, double–click Network Connections, right-click the desired connection, Properties, Advanced tab, Under Internet Connection Firewall, uncheck or check the Protect my computer and network by limiting or preventing access to this computer from the Internet check box. 10. How to Disable Firewall in Windows XP 11. Minimum System requirement of Windows XP, Vista, 2003 and 2008 12. Explain ping command. Ping is a basic Internet program that allows a user to verify that a particular IP address exists and can accept requests. Ping is used diagnostically to ensure that a host computer the user is trying to reach is actually operating. Ping works by sending an Internet Control Message Protocol (ICMP) Echo Request to a specified interface on the network and waiting for a reply. Ping can be used for troubleshooting to test connectivity and determine response time. 13. pst file location Win xp – c:doc & setting user name Local SettingsApplication DataMicrosoftOutlook 14. What is a port number ? a port number is part of the addressing information used to identify the senders and receivers of messages. Port numbers are most commonly used with TCP/IP connections 15. Where is the HOSTS file located C: windows system32driversetc
- 7. 16. Lan cable code – Straight – 1. White orange 2. Orange 3. White green 4. Blue 5. White blue 6. Green 7. White brawn 8. Brawn Cross - 1–3 2-6 3–1 4–4 5–5 6–2 7–7 8 – 8. 17. type of backup – Normal. - When an administrator chooses to use a normal backup, all selected files and folders are backed up and the archive attribute of all files are cleared. A normal backup does not use the archive attribute to determine which files to back up. A normal backup is used as the first step of any backup plan Copy. - Copy backup is a backup that copies all selected files but does not mark each file as having been backed up. In other words, the archive attribute is not cleared. Copying can be
- 8. carried out between normal and incremental backups because copying does not affect these other backup operations. Incremental. - A backup of those files which have changed since the last backup of any type. An incremental backup is the fastest backup and requires the least storage space on the backup media. However, incremental backups also require the longest time and many tapes to restore. Differential - A backup of those files which have changes since the last full backup. Should be performed at regular intervals. Daily. - Daily backup refers to making daily copies of data so that these additional copies may be used to restore the original after a data loss event. Daily backups can also be combined with weekly or monthly full backups, according to the backup scenario used 18. command to create domain – dcpramo. The Active Directory Database is Stored in %SYSTEM ROOT%NDTS folder. the active directory uses the sysvol folder as well The file is called as ntds.dit. Along with this file there are other files also present in this folder. The files are created when you run dcpromo. What is DNS? Domain Name System (DNS) is a database system that translates a computer's fully qualified domain name into an IP address.
- 9. 19. 20. Explain different RAID levels 21. Explain APIPA, IP address and Subnet mask 22. Difference between IP v4 and IP v6 23. How to remove virus from a computer 24. How to make a computer run faster 25. What is attrib command ? 26. What is edit command ? 27. How to copy a file or folder using copy command 28. How to format the hard disk using command line utilities 29. Explain Cookies 30. 31. How to boot the computer in Safe mode 32. What is Disk clean up, Disk Defragmentation, Device manager and System Restore 33. USB port Vs Firewire port 34. How to install a printer in Windows XP 35. 36. Explain mkdir, rmdir and chdir commands 37. Types of hard disk 38. Difference between primary and secondary partition 39. Types of back in Window OS 40. Differential Backup Vs Incremental Backup Vs Copy backup 41. What is remote desktop. 42. Recovery Console Vs Automated System Recovery 43. What is NTLDR file 44. How to tackle "missing NTLDR file" error 45. How many bytes are there in MAC address 46. Range of Class A IP address 47. Range of Class B IP address 48. Range of Class C IP address 49. Default subnet mask of Class A, Class B and Class C IP address 50. What is BSOD (Blue Screen of Death) and how to overcome it 51. Difference between Preferred DNS and Alternate DNS server 52. Transmission speed of T1 carrier