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Sunday, May 9, 2010

Best keyboard shortcut

Getting used to using your keyboard exclusively and leaving your mouse behind will make you much more efficient at performing any task on any Windows system. I use the following keyboard shortcuts every day:

Windows key + R = Run menu

This is usually followed by:
cmd = Command Prompt
iexplore + "web address" = Internet Explorer
compmgmt.msc = Computer Management
dhcpmgmt.msc = DHCP Management
dnsmgmt.msc = DNS Management
services.msc = Services
eventvwr = Event Viewer
dsa.msc = Active Directory Users and Computers
dssite.msc = Active Directory Sites and Services
Windows key + E = Explorer

ALT + Tab = Switch between windows

ALT, Space, X = Maximize window

CTRL + Shift + Esc = Task Manager

Windows key + Break = System properties

Windows key + F = Search

Windows key + D = Hide/Display all windows

CTRL + C = copy

CTRL + X = cut

CTRL + V = paste

Also don't forget about the "Right-click" key next to the right Windows key on your keyboard. Using the arrows and that key can get just about anything done once you've opened up any program.


Keyboard Shortcuts

[Alt] and [Esc] Switch between running applications

[Alt] and letter Select menu item by underlined letter

[Ctrl] and [Esc] Open Program Menu

[Ctrl] and [F4] Close active document or group windows (does not work with some applications)

[Alt] and [F4] Quit active application or close current window

[Alt] and [-] Open Control menu for active document

Ctrl] Lft., Rt. arrow Move cursor forward or back one word

Ctrl] Up, Down arrow Move cursor forward or back one paragraph

[F1] Open Help for active application

Windows+M Minimize all open windows

Shift+Windows+M Undo minimize all open windows

Windows+F1 Open Windows Help

Windows+Tab Cycle through the Taskbar buttons

Windows+Break Open the System Properties dialog box



acessability shortcuts

Right SHIFT for eight seconds........ Switch FilterKeys on and off.

Left ALT +left SHIFT +PRINT SCREEN....... Switch High Contrast on and off.

Left ALT +left SHIFT +NUM LOCK....... Switch MouseKeys on and off.

SHIFT....... five times Switch StickyKeys on and off.

NUM LOCK...... for five seconds Switch ToggleKeys on and off.

explorer shortcuts

END....... Display the bottom of the active window.

HOME....... Display the top of the active window.

NUM LOCK+ASTERISK....... on numeric keypad (*) Display all subfolders under the selected folder.

NUM LOCK+PLUS SIGN....... on numeric keypad (+) Display the contents of the selected folder.

NUM LOCK+MINUS SIGN....... on numeric keypad (-) Collapse the selected folder.

LEFT ARROW...... Collapse current selection if it's expanded, or select parent folder.

RIGHT ARROW....... Display current selection if it's collapsed, or select first subfolder.




Type the following commands in your Run Box (Windows Key + R) or Start Run

devmgmt.msc = Device Manager
msinfo32 = System Information
cleanmgr = Disk Cleanup
ntbackup = Backup or Restore Wizard (Windows Backup Utility)
mmc = Microsoft Management Console
excel = Microsoft Excel (If Installed)
msaccess = Microsoft Access (If Installed)
powerpnt = Microsoft PowerPoint (If Installed)
winword = Microsoft Word (If Installed)
frontpg = Microsoft FrontPage (If Installed)
notepad = Notepad
wordpad = WordPad
calc = Calculator
msmsgs = Windows Messenger
mspaint = Microsoft Paint
wmplayer = Windows Media Player
rstrui = System Restore
netscp6 = Netscape 6.x
netscp = Netscape 7.x
netscape = Netscape 4.x
waol = America Online
control = Opens the Control Panel
control printers = Opens the Printers Dialog


internetbrowser

type in u're adress "google", then press [Right CTRL] and [Enter]
add www. and .com to word and go to it


For Windows XP:

Copy. CTRL+C
Cut. CTRL+X
Paste. CTRL+V
Undo. CTRL+Z
Delete. DELETE
Delete selected item permanently without placing the item in the Recycle Bin. SHIFT+DELETE
Copy selected item. CTRL while dragging an item
Create shortcut to selected item. CTRL+SHIFT while dragging an item
Rename selected item. F2
Move the insertion point to the beginning of the next word. CTRL+RIGHT ARROW
Move the insertion point to the beginning of the previous word. CTRL+LEFT ARROW
Move the insertion point to the beginning of the next paragraph. CTRL+DOWN ARROW
Move the insertion point to the beginning of the previous paragraph. CTRL+UP ARROW
Highlight a block of text. CTRL+SHIFT with any of the arrow keys
Select more than one item in a window or on the desktop, or select text within a document. SHIFT with any of the arrow keys
Select all. CTRL+A
Search for a file or folder. F3
View properties for the selected item. ALT+ENTER
Close the active item, or quit the active program. ALT+F4
Opens the shortcut menu for the active window. ALT+SPACEBAR
Close the active document in programs that allow you to have multiple documents open simultaneously. CTRL+F4
Switch between open items. ALT+TAB
Cycle through items in the order they were opened. ALT+ESC
Cycle through screen elements in a window or on the desktop. F6
Display the Address bar list in My Computer or Windows Explorer. F4
Display the shortcut menu for the selected item. SHIFT+F10
Display the System menu for the active window. ALT+SPACEBAR
Display the Start menu. CTRL+ESC
Display the corresponding menu. ALT+Underlined letter in a menu name
Carry out the corresponding command. Underlined letter in a command name on an open menu
Activate the menu bar in the active program. F10
Open the next menu to the right, or open a submenu. RIGHT ARROW
Open the next menu to the left, or close a submenu. LEFT ARROW
Refresh the active window. F5
View the folder one level up in My Computer or Windows Explorer. BACKSPACE
Cancel the current task. ESC
SHIFT when you insert a CD into the CD-ROM drive Prevent the CD from automatically playing.

Use these keyboard shortcuts for dialog boxes:

To Press
Move forward through tabs. CTRL+TAB
Move backward through tabs. CTRL+SHIFT+TAB
Move forward through options. TAB
Move backward through options. SHIFT+TAB
Carry out the corresponding command or select the corresponding option. ALT+Underlined letter
Carry out the command for the active option or button. ENTER
Select or clear the check box if the active option is a check box. SPACEBAR
Select a button if the active option is a group of option buttons. Arrow keys
Display Help. F1
Display the items in the active list. F4
Open a folder one level up if a folder is selected in the Save As or Open dialog box. BACKSPACE

If you have a Microsoft Natural Keyboard, or any other compatible keyboard that includes the Windows logo key and the Application key , you can use these keyboard shortcuts:


Display or hide the Start menu. WIN Key
Display the System Properties dialog box. WIN Key+BREAK
Show the desktop. WIN Key+D
Minimize all windows. WIN Key+M
Restores minimized windows. WIN Key+Shift+M
Open My Computer. WIN Key+E
Search for a file or folder. WIN Key+F
Search for computers. CTRL+WIN Key+F
Display Windows Help. WIN Key+F1
Lock your computer if you are connected to a network domain, or switch users if you are not connected to a network domain. WIN Key+ L
Open the Run dialog box. WIN Key+R
Open Utility Manager. WIN Key+U

accessibility keyboard shortcuts:

Switch FilterKeys on and off. Right SHIFT for eight seconds
Switch High Contrast on and off. Left ALT+left SHIFT+PRINT SCREEN
Switch MouseKeys on and off. Left ALT +left SHIFT +NUM LOCK
Switch StickyKeys on and off. SHIFT five times
Switch ToggleKeys on and off. NUM LOCK for five seconds
Open Utility Manager. WIN Key+U

shortcuts you can use with Windows Explorer:


Display the bottom of the active window. END
Display the top of the active window. HOME
Display all subfolders under the selected folder. NUM LOCK+ASTERISK on numeric keypad (*)
Display the contents of the selected folder. NUM LOCK+PLUS SIGN on numeric keypad (+)
Collapse the selected folder. NUM LOCK+MINUS SIGN on numeric keypad (-)
Collapse current selection if it's expanded, or select parent folder. LEFT ARROW
Display current selection if it's collapsed, or select first subfolder. RIGHT ARROW

BIOS Code Manual

BIOS Beep Codes

When a computer is first turned on, or rebooted, its BIOS performs a power-on self test (POST) to test the system's hardware, checking to make sure that all of the system's hardware components are working properly. Under normal circumstances, the POST will display an error message; however, if the BIOS detects an error before it can access the video card, or if there is a problem with the video card, it will produce a series of beeps, and the pattern of the beeps indicates what kind of problem the BIOS has detected.
Because there are many brands of BIOS, there are no standard beep codes for every BIOS.

The two most-used brands are AMI (American Megatrends International) and Phoenix.

Below are listed the beep codes for AMI systems, and here are the beep codes for Phoenix systems.


AMI Beep Codes

Beep Code Meaning
1 beep DRAM refresh failure. There is a problem in the system memory or the motherboard.
2 beeps Memory parity error. The parity circuit is not working properly.
3 beeps Base 64K RAM failure. There is a problem with the first 64K of system memory.
4 beeps System timer not operational. There is problem with the timer(s) that control functions on the motherboard.
5 beeps Processor failure. The system CPU has failed.
6 beeps Gate A20/keyboard controller failure. The keyboard IC controller has failed, preventing gate A20 from switching the processor to protect mode.
7 beeps Virtual mode exception error.
8 beeps Video memory error. The BIOS cannot write to the frame buffer memory on the video card.
9 beeps ROM checksum error. The BIOS ROM chip on the motherboard is likely faulty.
10 beeps CMOS checksum error. Something on the motherboard is causing an error when trying to interact with the CMOS.
11 beeps Bad cache memory. An error in the level 2 cache memory.
1 long beep, 2 short Failure in the video system.
1 long beep, 3 short A failure has been detected in memory above 64K.
1 long beep, 8 short Display test failure.
Continuous beeping A problem with the memory or video.
BIOS Beep Codes


Phoenix Beep Codes

Phoenix uses sequences of beeps to indicate problems. The "-" between each number below indicates a pause between each beep sequence. For example, 1-2-3 indicates one beep, followed by a pause and two beeps, followed by a pause and three beeps. Phoenix version before 4.x use 3-beep codes, while Phoenix versions starting with 4.x use 4-beep codes. Click here for AMI BIOS beep codes.
4-Beep Codes
Beep Code Meaning
1-1-1-3 Faulty CPU/motherboard. Verify real mode.
1-1-2-1 Faulty CPU/motherboard.
1-1-2-3 Faulty motherboard or one of its components.
1-1-3-1 Faulty motherboard or one of its components. Initialize chipset registers with initial POST values.
1-1-3-2 Faulty motherboard or one of its components.
1-1-3-3 Faulty motherboard or one of its components. Initialize CPU registers.
1-1-3-2
1-1-3-3
1-1-3-4 Failure in the first 64K of memory.
1-1-4-1 Level 2 cache error.
1-1-4-3 I/O port error.
1-2-1-1 Power management error.
1-2-1-2
1-2-1-3 Faulty motherboard or one of its components.
1-2-2-1 Keyboard controller failure.
1-2-2-3 BIOS ROM error.
1-2-3-1 System timer error.
1-2-3-3 DMA error.
1-2-4-1 IRQ controller error.
1-3-1-1 DRAM refresh error.
1-3-1-3 A20 gate failure.
1-3-2-1 Faulty motherboard or one of its components.
1-3-3-1 Extended memory error.
1-3-3-3
1-3-4-1
1-3-4-3 Error in first 1MB of system memory.
1-4-1-3
1-4-2-4 CPU error.
1-4-3-1
2-1-4-1 BIOS ROM shadow error.
1-4-3-2
1-4-3-3 Level 2 cache error.
1-4-4-1
1-4-4-2
2-1-1-1 Faulty motherboard or one of its components.
2-1-1-3
2-1-2-1 IRQ failure.
2-1-2-3 BIOS ROM error.
2-1-2-4
2-1-3-2 I/O port failure.
2-1-3-1
2-1-3-3 Video system failure.
2-1-1-3
2-1-2-1 IRQ failure.
2-1-2-3 BIOS ROM error.
2-1-2-4 I/O port failure.
2-1-4-3
2-2-1-1 Video card failure.
2-2-1-3
2-2-2-1
2-2-2-3 Keyboard controller failure.
2-2-3-1 IRQ error.
2-2-4-1 Error in first 1MB of system memory.
2-3-1-1
2-3-3-3 Extended memory failure.
2-3-2-1 Faulty motherboard or one of its components.
2-3-2-3
2-3-3-1 Level 2 cache error.
2-3-4-1
2-3-4-3 Motherboard or video card failure.
2-3-4-1
2-3-4-3
2-4-1-1 Motherboard or video card failure.
2-4-1-3 Faulty motherboard or one of its components.
2-4-2-1 RTC error.
2-4-2-3 Keyboard controller error.
2-4-4-1 IRQ error.
3-1-1-1
3-1-1-3
3-1-2-1
3-1-2-3 I/O port error.
3-1-3-1
3-1-3-3 Faulty motherboard or one of its components.
3-1-4-1
3-2-1-1
3-2-1-2 Floppy drive or hard drive failure.
3-2-1-3 Faulty motherboard or one of its components.
3-2-2-1 Keyboard controller error.
3-2-2-3
3-2-3-1
3-2-4-1 Faulty motherboard or one of its components.
3-2-4-3 IRQ error.
3-3-1-1 RTC error.
3-3-1-3 Key lock error.
3-3-3-3 Faulty motherboard or one of its components.
3-3-3-3
3-3-4-1
3-3-4-3
3-4-1-1
3-4-1-3
3-4-2-1
3-4-2-3
3-4-3-1
3-4-4-1
3-4-4-4 Faulty motherboard or one of its components.
4-1-1-1 Floppy drive or hard drive failure.
4-2-1-1
4-2-1-3
4-2-2-1 IRQ failure.
4-2-2-3
4-2-3-1
4-2-3-3
4-2-4-1 Faulty motherboard or one of its components.
4-2-4-3 Keyboard controller error.
4-3-1-3
4-3-1-4
4-3-2-1
4-3-2-2
4-3-3-1
4-3-4-1
4-3-4-3 Faulty motherboard or one of its components.
4-3-3-2
4-3-3-4 IRQ failure.
4-3-3-3
4-3-4-2 Floppy drive or hard drive failure.
3-Beep Codes
Beep Code Meaning
1-1-2 Faulty CPU/motherboard.
1-1-3 Faulty motherboard/CMOS read-write failure.
1-1-4 Faulty BIOS/BIOS ROM checksum error.
1-2-1 System timer not operational. There is a problem with the timer(s) that control functions on the motherboard.
1-2-2
1-2-3 Faulty motherboard/DMA failure.
1-3-1 Memory refresh failure.
1-3-2
1-3-3
1-3-4 Failure in the first 64K of memory.
1-4-1 Address line failure.
1-4-2 Parity RAM failure.
1-4-3 Timer failure.
1-4-4 NMI port failure.
2-_-_ Any combination of beeps after 2 indicates a failure in the first 64K of memory.
3-1-1 Master DMA failure.
3-1-2 Slave DMA failure.
3-1-3
3-1-4 Interrupt controller failure.
3-2-4 Keyboard controller failure.
3-3-1
3-3-2 CMOS error.
3-3-4 Video card failure.
3-4-1 Video card failure.
4-2-1 Timer failure.
4-2-2 CMOS shutdown failure.
4-2-3 Gate A20 failure.
4-2-4 Unexpected interrupt in protected mode.
4-3-1 RAM test failure.
4-3-3 Timer failure.
4-3-4 Time of day clock failure.
4-4-1 Serial port failure.
4-4-2 Parallel port failure.
4-4-3 Math coprocessor.

A basic guide to internet !!!!!!

The Internet is a computer network made up of thousands of networks worldwide. No one knows exactly how many computers are connected to the Internet. It is certain, however, that these number in the millions.

No one is in charge of the Internet. There are organizations which develop technical aspects of this network and set standards for creating applications on it, but no governing body is in control. The Internet backbone, through which Internet traffic flows, is owned by private companies.

All computers on the Internet communicate with one another using the Transmission Control Protocol/Internet Protocol suite, abbreviated to TCP/IP. Computers on the Internet use a client/server architecture. This means that the remote server machine provides files and services to the user's local client machine. Software can be installed on a client computer to take advantage of the latest access technology.

An Internet user has access to a wide variety of services: electronic mail, file transfer, vast information resources, interest group membership, interactive collaboration, multimedia displays, real-time broadcasting, shopping opportunities, breaking news, and much more.

The Internet consists primarily of a variety of access protocols. Many of these protocols feature programs that allow users to search for and retrieve material made available by the protocol.


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COMPONENTS OF THE INTERNET

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WORLD WIDE WEB
The World Wide Web (abbreviated as the Web or WWW) is a system of Internet servers that supports hypertext to access several Internet protocols on a single interface. Almost every protocol type available on the Internet is accessible on the Web. This includes e-mail, FTP, Telnet, and Usenet News. In addition to these, the World Wide Web has its own protocol: HyperText Transfer Protocol, or HTTP. These protocols will be explained later in this document.

The World Wide Web provides a single interface for accessing all these protocols. This creates a convenient and user-friendly environment. It is no longer necessary to be conversant in these protocols within separate, command-level environments. The Web gathers together these protocols into a single system. Because of this feature, and because of the Web's ability to work with multimedia and advanced programming languages, the Web is the fastest-growing component of the Internet.

The operation of the Web relies primarily on hypertext as its means of information retrieval. HyperText is a document containing words that connect to other documents. These words are called links and are selectable by the user. A single hypertext document can contain links to many documents. In the context of the Web, words or graphics may serve as links to other documents, images, video, and sound. Links may or may not follow a logical path, as each connection is programmed by the creator of the source document. Overall, the Web contains a complex virtual web of connections among a vast number of documents, graphics, videos, and sounds.

Producing hypertext for the Web is accomplished by creating documents with a language called HyperText Markup Language, or HTML. With HTML, tags are placed within the text to accomplish document formatting, visual features such as font size, italics and bold, and the creation of hypertext links. Graphics and multimedia may also be incorporated into an HTML document. HTML is an evolving language, with new tags being added as each upgrade of the language is developed and released. The World Wide Web Consortium (W3C), led by Web founder Tim Berners-Lee, coordinates the efforts of standardizing HTML. The W3C now calls the language XHTML and considers it to be an application of the XML language standard.

The World Wide Web consists of files, called pages or home pages, containing links to documents and resources throughout the Internet.

The Web provides a vast array of experiences including multimedia presentations, real-time collaboration, interactive pages, radio and television broadcasts, and the automatic "push" of information to a client computer. Programming languages such as Java, JavaScript, Visual Basic, Cold Fusion and XML are extending the capabilities of the Web. A growing amount of information on the Web is served dynamically from content stored in databases. The Web is therefore not a fixed entity, but one that is in a constant state of development and flux.

For more complete information about the World Wide Web, see Understanding The World Wide Web.

E-MAIL
Electronic mail, or e-mail, allows computer users locally and worldwide to exchange messages. Each user of e-mail has a mailbox address to which messages are sent. Messages sent through e-mail can arrive within a matter of seconds.

A powerful aspect of e-mail is the option to send electronic files to a person's e-mail address. Non-ASCII files, known as binary files, may be attached to e-mail messages. These files are referred to as MIME attachments.MIME stands for Multimedia Internet Mail Extension, and was developed to help e-mail software handle a variety of file types. For example, a document created in Microsoft Word can be attached to an e-mail message and retrieved by the recipient with the appropriate e-mail program. Many e-mail programs, including Eudora, Netscape Messenger, and Microsoft Outlook, offer the ability to read files written in HTML, which is itself a MIME type.

TELNET
Telnet is a program that allows you to log into computers on the Internet and use online databases, library catalogs, chat services, and more. There are no graphics in Telnet sessions, just text. To Telnet to a computer, you must know its address. This can consist of words (locis.loc.gov) or numbers (140.147.254.3). Some services require you to connect to a specific port on the remote computer. In this case, type the port number after the Internet address. Example: telnet nri.reston.va.us 185.

Telnet is available on the World Wide Web. Probably the most common Web-based resources available through Telnet have been library catalogs, though most catalogs have since migrated to the Web. A link to a Telnet resource may look like any other link, but it will launch a Telnet session to make the connection. A Telnet program must be installed on your local computer and configured to your Web browser in order to work.

With the increasing popularity of the Web, Telnet has become less frequently used as a means of access to information on the Internet.

FTP
FTP stands for File Transfer Protocol. This is both a program and the method used to transfer files between computers. Anonymous FTP is an option that allows users to transfer files from thousands of host computers on the Internet to their personal computer account. FTP sites contain books, articles, software, games, images, sounds, multimedia, course work, data sets, and more.

If your computer is directly connected to the Internet via an Ethernet cable, you can use one of several PC software programs, such as WS_FTP for Windows, to conduct a file transfer.

FTP transfers can be performed on the World Wide Web without the need for special software. In this case, the Web browser will suffice. Whenever you download software from a Web site to your local machine, you are using FTP. You can also retrieve FTP files via search engines such as FtpFind, located at /http://www.ftpfind.com/. This option is easiest because you do not need to know FTP program commands.

E-MAIL DISCUSSION GROUPS
One of the benefits of the Internet is the opportunity it offers to people worldwide to communicate via e-mail. The Internet is home to a large community of individuals who carry out active discussions organized around topic-oriented forums distributed by e-mail. These are administered by software programs. Probably the most common program is the listserv.

A great variety of topics are covered by listservs, many of them academic in nature. When you subscribe to a listserv, messages from other subscribers are automatically sent to your electronic mailbox. You subscribe to a listserv by sending an e-mail message to a computer program called a listserver. Listservers are located on computer networks throughout the world. This program handles subscription information and distributes messages to and from subscribers. You must have a e-mail account to participate in a listserv discussion group. Visit Tile.net at /http://tile.net/ to see an example of a site that offers a searchablecollection of e-mail discussion groups.

Majordomo and Listproc are two other programs that administer e-mail discussion groups. The commands for subscribing to and managing your list memberships are similar to those of listserv.

USENET NEWS
Usenet News is a global electronic bulletin board system in which millions of computer users exchange information on a vast range of topics. The major difference between Usenet News and e-mail discussion groups is the fact that Usenet messages are stored on central computers, and users must connect to these computers to read or download the messages posted to these groups. This is distinct from e-mail distribution, in which messages arrive in the electronic mailboxes of each list member.

Usenet itself is a set of machines that exchanges messages, or articles, from Usenet discussion forums, called newsgroups. Usenet administrators control their own sites, and decide which (if any) newsgroups to sponsor and which remote newsgroups to allow into the system.

There are thousands of Usenet newsgroups in existence. While many are academic in nature, numerous newsgroups are organized around recreational topics. Much serious computer-related work takes place in Usenet discussions. A small number of e-mail discussion groups also exist as Usenet newsgroups.

The Usenet newsfeed can be read by a variety of newsreader software programs. For example, the Netscape suite comes with a newsreader program called Messenger. Newsreaders are also available as standalone products.

FAQ, RFC, FYI
FAQ stands for Frequently Asked Questions. These are periodic postings to Usenet newsgroups that contain a wealth of information related to the topic of the newsgroup. Many FAQs are quite extensive. FAQs are available by subscribing to individual Usenet newsgroups. A Web-based collection of FAQ resources has been collected by The Internet FAQ Consortium and is available at /http://www.faqs.org/.

RFC stands for Request for Comments. These are documents created by and distributed to the Internet community to help define the nuts and bolts of the Internet. They contain both technical specifications and general information.

FYI stands for For Your Information. These notes are a subset of RFCs and contain information of interest to new Internet users.

Links to indexes of all three of these information resources are available on the University Libraries Web site at /http://library.albany.edu/reference/faqs.html.

CHAT & INSTANT MESSENGING
Chat programs allow users on the Internet to communicate with each other by typing in real time. They are sometimes included as a feature of a Web site, where users can log into the "chat room" to exchange comments and information about the topics addressed on the site. Chat may take other, more wide-ranging forms. For example, America Online is well known for sponsoring a number of topical chat rooms.

Internet Relay Chat (IRC) is a service through which participants can communicate to each other on hundreds of channels. These channels are usually based on specific topics. While many topics are frivolous, substantive conversations are also taking place. To access IRC, you must use an IRC software program.

A variation of chat is the phenomenon of instant messenging. With instant messenging, a user on the Web can contact another user currently logged in and type a conversation. Most famous is America Online's Instant Messenger. ICQ, MSN and Yahoo are other commonly-used chat programs.

Other types of real-time communication are addressed in the tutorial Understanding the World Wide Web.

MUD/MUSH/MOO/MUCK/DUM/MUSE
MUD stands for Multi User Dimension. MUDs, and their variations listed above, are multi-user virtual reality games based on simulated worlds. Traditionally text based, graphical MUDs now exist. There are MUDs of all kinds on the Internet, and many can be joined free of charge. For more information, read one of the FAQs devoted to MUDs available at the FAQ site at

Friday, March 5, 2010

Check out Sixth Sense - The Amazing Indian Invention - paper laptop - IndiansInLondon.net

Title: Sixth Sense - The Amazing Indian Invention - paper laptop - IndiansInLondon.net
Link: http://gotaf.socialtwist.com/redirect?l=-489192934747663041711

Monday, December 7, 2009

Dear all

Here by some good news which i like to share with you all !

As network professional you may need to learn juniper network as well, Juniper network is offering some free training as well you can get all resource from its webpage,

here is its Link Address


please leave your comment .....

Regard
your
dev

Thursday, July 16, 2009

hello my dear Friends

Hello my All Dear Friends

i hope u are enjoying this blog. please let me know your view ! if you anyone intrested to post something new please please inform me ! i would love to give u more information on same. or even if you want your own post please mail me i will post here.

lets grow together and make better world

luv
Dev

Sunday, June 8, 2008

Interview Question and Answers

 

 

 

Hello friend

Here one more try for you to get job in network field wish it will be helpful to you. on that answers I passed several hours for you only so you can get answer just directly....... wish ya luck

 

Interview question for network

1. What are 10Base2, 10Base5 and 10BaseT Ethernet LANs?

 

  Media Type Max. Segment Length Max. # Nodes/Segment
10Base5 Thick coaxial 500 meters 100
10Base2 RG58 (thin) coaxial 185 meters 30
10BaseT UTP 100 meters 1024
10BaseF (FOIRL) Fiber-optic 2,000 meters 1024k

 

2. What is the difference between an unspecified passive open and a fully specified passive open

An unspecified passive open has the server waiting for a connection request from a client. A fully specified passive open has the server waiting for a connection from a specific client.

 

3. Explain the function of Transmission Control Block

A TCB is a complex data structure that contains a considerable amount of information about each connection.

 

4. What is a Management Information Base (MIB)

Formal description of a set of network objects that can be managed using the Simple Network Management Protocol (SNMP).

 

4. What is anonymous FTP and why would you use it?

No authentication needed.

 

5. What is a pseudo tty?

A pseudo tty or false terminal enables external machines to connect through Telnet or rlogin. Without a pseudo tty, no connection can take place

 

6. What does the Mount protocol do?

The Mount protocol returns a file handle and the name of the file system in which a requested file resides. The message is sent to the client from the server after reception of a client's request.

 

7. What is External Data Representation?

 

8. What is the Network Time Protocol?

Synchronizing the clocks of computer systems over packet-switched, variable-latency data networks. NTP uses UDP as its transport layer. It is designed particularly to resist the effects of variable latency.

 

9. What is a DNS resource record?

Entry in a name server's database.

 

10. What protocol is used by DNS name servers?

Tcp/udp port 53

 

11. What is the difference between interior and exterior neighbor gateways?

Interior gateways connect LANs of one organization, whereas exterior gateways connect the organization to the outside world.

 

12. What is the HELLO protocol used for?

To establishing maintain and negotiation of neighbor ship

 

13. What are the advantages and disadvantages of the three types of routing tables?

The three types of routing tables are fixed, dynamic, and fixed central

The fixed table  must be manually modified every time there is a change

A dynamic table changes its information based on network traffic, reducing the amount of manual maintenance

 

A fixed central table lets a manager modify only one table, which is then read by other devices. The fixed central table reduces the need to update each machine's table, as with the fixed table.

 

14. What is source route?

 

15. What is RIP (Routing Information Protocol)?

It is a simple protocol used to exchange information between the routers.

 

16. What is SLIP (Serial Line Interface Protocol)?

It is a very simple protocol used for transmission of IP datagrams across a serial line.

 

17. What is Proxy ARP?

It is using a router to answer ARP requests. This will be done when the originating host believes that a destination is local, when in fact is lies beyond router.

 

18. What is OSPF?

It is an Internet routing protocol that scales well, can route traffic along multiple paths, and uses knowledge of an Internet's topology to make accurate routing decisions.

It is an Internet routing protocol that scales well, can route traffic along multiple paths, and uses knowledge of an Internet’s topology to make accurate routing decisions

 

19. What is Kerberos?

It is an authentication service developed at the Massachusetts Institute of Technology. Kerberos uses encryption to prevent intruders from discovering passwords and gaining unauthorized access to files.

 

20. What is a Multi-homed Host?

It is a host that has a multiple network interfaces and that requires multiple IP addresses is called as a Multi-homed Host

 

21. What is NVT (Network Virtual Terminal)?

It is a set of rules defining a very simple virtual terminal interaction. The NVT is used in the start of a Telnet session

 

22. What is Gateway-to-Gateway protocol?

It is a protocol formerly used to exchange routing information between Internet core routers.

 

23. What is BGP (Border Gateway Protocol)?

It is a protocol used to advertise the set of networks that can be reached with in an autonomous system. BGP enables this information to be shared with the autonomous system. This is newer than EGP (Exterior Gateway Protocol).

 

24. What is autonomous system?

It is a collection of routers under the control of a single administrative authority and that uses a common Interior Gateway Protocol.

 

25. What is EGP (Exterior Gateway Protocol)?

It is the protocol the routers in neighboring autonomous systems use to identify the set of networks that can be reached within or via each autonomous system.

26. What is IGP (Interior Gateway Protocol)?

It is any routing protocol used within an autonomous system.

 

27. What is Mail Gateway?

It is a system that performs a protocol translation between different electronic mail delivery protocols.

 

28. What is wide-mouth frog?

Wide-mouth frog is the simplest known key distribution center (KDC) authentication protocol.

 

29. What are Digrams and Trigrams?

The most common two letter combinations are called as digrams. e.g. th, in, er, re and an. The most common three letter combinations are called as trigrams. e.g. the, ing, and, and ion.

 

30. What is silly window syndrome?

It is a problem that can ruin TCP performance. This problem occurs when data are passed to the sending TCP entity in large blocks, but an interactive application on the receiving side reads 1 byte at a time.

 

31. What is region?

When hierarchical routing is used, the routers are divided into what we call regions, with each router knowing all the details about how to route packets to destinations within its own region, but knowing nothing about the internal structure of other regions.

 

32. What is multicast routing?

Sending a message to a group is called multicasting, and its routing algorithm is called multicast routing.

 

33. What is traffic shaping?

One of the main causes of congestion is that traffic is often busy. If hosts could be made to transmit at a uniform rate, congestion would be less common. Another open loop method to help manage congestion is forcing the packet to be transmitted at a more predictable rate. This is called traffic shaping

 

34. What is packet filter?

Packet filter is a standard router equipped with some extra functionality. The extra functionality allows every incoming or outgoing packet to be inspected. Packets meeting some criterion are forwarded normally. Those that fail the test are dropped.

Example : IDS/IPS

 

35. What is virtual path/ virtual channel?

Along any transmission path from a given source to a given destination, a group of virtual circuits can be grouped together into what is called path.

 

36. What is logical link control?

One of two sublayers of the data link layer of OSI reference model, as defined by the IEEE 802 standard. This sublayer is responsible for maintaining the link between computers when they are sending data across the physical network connection

 

37. Why should you care about the OSI Reference Model?

It provides a framework for discussing network operations and design.

 

38. What is the difference between routable and non- routable protocols?

Routable protocols can work with a router and can be used to build large networks. Non-Routable protocols are designed to work on small, local networks and cannot be used with a router

39. What is MAU?

In token Ring , hub is called Multistation Access Unit(MAU).

 

40. Explain 5-4-3 rule.

In a Ethernet network, between any two points on the network, there can be no more than five network segments or four repeaters, and of those five segments only three of segments can be populated.

 

41. What is the difference between TFTP and FTP application layer protocols?

The Trivial File Transfer Protocol (TFTP) allows a local host to obtain files from a remote host but does not provide reliability or security. It uses the fundamental packet delivery services offered by UDP.

The File Transfer Protocol (FTP) is the standard mechanism provided by TCP / IP for copying a file from one host to another. It uses the services offered by TCP and so is reliable and secure. It establishes two connections (virtual circuits) between the hosts, one for data transfer and another for control information

 

42. What is the range of addresses in the classes of internet addresses?

Class A 0.0.0.0 - 127.255.255.255

Class B 128.0.0.0 - 191.255.255.255

Class C 192.0.0.0 - 223.255.255.255

Class D 224.0.0.0 - 239.255.255.255

Class E 240.0.0.0 - 247.255.255.255

43. What is the minimum and maximum length of the header in the TCP segment and IP datagram?

The header should have a minimum length of 20 bytes and can have a maximum length of 60 bytes.

44. What is difference between ARP and RARP?

ARP: map ip Network addresses to the hardware

RARP: Map MAC address to IP address

 

45. What is ICMP?

ICMP is Internet Control Message Protocol, a network layer protocol of the TCP/IP suite used by hosts and gateways to send notification of datagram problems back to the sender. It uses the echo test / reply to test whether a destination is reachable and responding. It also handles both control and error messages. Example: PING, traceroute

 

46. What are the data units at different layers of the TCP / IP protocol suite?

The data unit created at the application layer is called a message, at the transport layer the data unit created is called either a segment or an user datagram, at the network layer the data unit created is called the datagram, at the data link layer the datagram is encapsulated in to a frame and finally transmitted as signals along the transmission media.

 

47. What is Project 802?

It is a project started by IEEE to set standards that enable intercommunication between equipment from a variety of manufacturers

802.1 is an internetworking standard for compatibility of different LANs and MANs across protocols.

 

48. What is Bandwidth?

Every line has an upper limit and a lower limit on the frequency of signals it can carry. This limited range is called the bandwidth.

 

49. Difference between bit rate and baud rate?

bits transmitted during one second

baud rate refers to the number of signal units per second

bits.baud rate = bit rate / no-of-bits represented by each signal shift

 

50. What is MAC address?

Address for a device

 

51. What is attenuation?

The degeneration of a signal over distance

 

52. What is cladding?

A layer of a glass surrounding the center fiber of glass inside a fiber-optic cable.

 

53. What is RAID?

A method for providing fault tolerance by using multiple hard disk drives.

 

54. What is NETBIOS and NETBEUI?

NETBIOS is a programming interface that allows I/O requests to be sent to and received from a remote computer and it hides the networking hardware from applications.

NETBEUI is NetBIOS extended user interface. A transport protocol designed by Microsoft and IBM for the use on small subnets.

 

55. What is redirector?

Redirector is software that intercepts file or prints I/O requests and translates them into network requests. This comes under presentation layer

 

56. What is Beaconing?

The process that allows a network to self-repair networks problems. The stations on the network notify the other stations on the ring when they are not receiving the transmissions. Beaconing is used in Token ring and FDDI networks.

 

57. What is terminal emulation, in which layer it comes?

Telnet is also called as terminal emulation. It belongs to application layer.

 

58. What is frame relay, in which layer it comes?

Frame relay is a packet switching technology. It will operate in the data link layer.

 

59. What do you meant by “triple X” in Networks?

triple X this term use in packet assembler/disassembler.

X.3, X.28, X.29

 

60. What is SAP?

system applications products and databases

 

61. What is subnet?

A generic term for section of a large networks usually separated by a bridge or router.

 

62. What is Brouter?

Short for bridge router and pronounced BROW-ter, a device that functions as both a router and a bridge. A brouter understands how to route specific types of packets, such as TCP/IP packets. Any other packets it receives are simply forwarded to other network(s) connected to the device (this is the bridge function).

 

63. How Gateway is different from Routers?

A gateway operates at the upper levels of the OSI model and translates information between two completely different network architectures or data formats.

 

64. What are the different type of networking / internetworking devices?

1) Hub

2) Switch, Bridge

3) Router, layer-3 switch Gateways

4) Hosts, printers...etc.

 

65. What is mesh network?

A network in which there are multiple network links between computers to provide multiple paths for data to travel.

 

66. What is passive topology?

When the computers on the network simply listen and receive the signal, they are referred to as passive because they don’t amplify the signal in any way. Example for passive topology - linear bus.

67. What are the important topologies for networks?

BUS topology:

In this each computer is directly connected to primary network cable in a single line.

Advantages:

Inexpensive, easy to install, simple to understand, easy to extend.

STAR topology:

In this all computers are connected using a central hub.

Advantages:

Can be inexpensive, easy to install and reconfigure and easy to trouble shoot physical problems.

RING topology:

In this all computers are connected in loop.

Advantages:

All computers have equal access to network media, installation can be simple, and signal does not degrade as much as in other topologies because each computer regenerates it.

 

68. What are major types of networks and explain?

Server-based network

Peer-to-peer network

Peer-to-peer network, computers can act as both servers sharing resources and as clients using the resources.

Server-based networks provide centralized control of network resources and rely on server computers to provide security and network administration

 

69. What is Protocol Data Unit?

The data unit in the LLC level is called the protocol data unit (PDU)

 

70. What is difference between baseband and broadband transmission?

In a baseband transmission, the entire bandwidth of the cable is consumed by a single signal. In broadband transmission, signals are sent on multiple frequencies, allowing multiple signals to be sent simultaneously.

71. What are the possible ways of data exchange?

(i) Simplex   (ii) Half-duplex   (iii) Full-duplex.

 

72. What are the types of Transmission media?

Guided Media:

These are those that provide a conduit from one device to another that include twisted-pair, coaxial cable and fiber-optic cable. A signal traveling along any of these media is directed and is contained by the physical limits of the medium. Twisted-pair and coaxial cable use metallic that accept and transport signals in the form of electrical current. Optical fiber is a glass or plastic cable that accepts and transports signals in the form of light.

Unguided Media:

This is the wireless media that transport electromagnetic waves without using a physical conductor. Signals are broadcast either through air. This is done through radio communication, satellite communication and cellular telephony.

 

73. What is point-to-point protocol?

A communications protocol used to connect computers to remote networking services including Internet service providers.

 

74. What are the two types of transmission technology available?

(i) Broadcast and (ii) point-to-point

 

75. Difference between the communication and transmission?

Transmission is a physical movement of information and concern issues like bit polarity, synchronisation, clock etc.Communication means the meaning full exchange of information between two communication media.

76. What is a different between switch and Hub?

Hub work at layer 1 where switch work at layer 2, hub is known as dumb device where switch are smart device

 

77. What are the Advantages and Disadvantages of DHCP?

Advantages:
Your IP address remains the same
so that you can run Internet services that require your IP address to remain the same in order for them to work properly (ie. Web Server, FTP Server).
If, for some reason, the RPI DHCP server is having difficulties handing out IP address, you will still be able to access the web, since your IP is predetermined.
Disadvantages:
You will only be able to effectively use your static IP address from your place of residence. You will be unable to use the web from other places on campus.
Configuring the network settings on your computer is more difficult for static IP than for DHCP, since DHCP is automatic and static IP is manual.

 

78. What is ERD(Emergency Repair Disk)?

ERD is a diskette that creates backups of important system files and settings and is used to help troubleshoot fix issues for Microsoft WINNT and WIN 2000.

 

79. What is the difference between POP3 and IMAP Mail Server?

POP3 is Email clients download your emails onto your computer. Using a specialized email program such as Outlook Express or Apple Mail has the advantage of giving you complete control over your email; every email you receive is placed on your computer and you can keep as many large file attachments as you want.

IMAP is protocol that is being used in webmail. Checking your email through our webmail is similar to using Hotmail or YAHOO! Mail. You never actually copy your messages to your computer; in fact, you are looking at them through your web browser on somebody else's computer. When you are not online, you are not able to see your email.

 

80. What is .ost file?

An OST file (.ost) is an offline folder file in Microsoft Outlook. Offline folders make it possible for the user to work offline and then to synchronize changes with the Exchange server the next time they connect. The ability to work offline is useful in environments with limited or unreliable connectivity.

 

81. What’s the difference between DNS and WINS 'Windows Internet Name Service'?

DNS maps TCP/IP host names to IP addresses and WINS maps NetBIOS host names to IP addresses

 

82. How can we create VPN to connect to branch office of the same office.what would be the preliminary requirement?

Best way to connect branch offices via VPN is to have VPN concentrator (Cisco, Nortel or a SOHO VPN enabled routers) installed and create LAN-to-LAN VPN tunnels between the offices

 

83. Why should we care about the OSI Reference Model? What is the main purpose for creating this osi model? Why it is a layered model?

 

84. What is layer-3 switch?

A switch who can handle routing also known as layer 3 switch

 

85. What is an email client? What is difference between email client and web mail?

Email clients download your emails onto your computer

Checking your email through our webmail is similar to using Hotmail or YAHOO! Mail

 

86. What is the vlan? How it is work?

Vlan= virtual LAN

It’s separated LAN in to logical sub LAN, it can help by limiting broadcast in LAN and improve network security

 

87. Name three network tools used to determine where network connectivity is lost between two sites A&B.

Ping

Traceroute

Pathping

 

88. Which protocol is used for retrieving mails?

IMAP 4, POP3

 

89. What is piggy backing?

Occurs when an authorized person allows (intentionally or unintentionally) others to pass through a secure door

 

90. What is the default subnet mask for an ipv6 address?

/32 OR 255.255.255.255.0

91. What is fragmentation of a packet?

Every packet-based network has an MTU (Maximum Transmission Unit) size. The MTU is the size of the largest packet which that network can transmit.

Packets larger than the allowable MTU must be divided into multiple smaller packets, or fragments, to enable them to traverse the network.

 

92. What is MTU of a link?

MTU (Maximum Transmission Unit), The MTU is the size of the largest packet which that network can transmit.

Ethernet: 1500, token ring 4096

 

93. Name any field of IP header that can prevent a packet to loop infinitely?

TTL field of ip header.

 

94. Under what situations a packet can go into infinite loop in a network?

if there are more than one way for reaching a particular router from the same source router

 

95. Describe a 3-way TCP/IP Handshake.

The active open is performed by sending a SYN to the server.
In response, the server replies with a SYN-ACK.
Finally the client sends an ACK back to the server.

 

96. What is a default gateway?

The exit-point from one network and entry-way into another network, often the router of the network.

 

97. How do you set a default route on an IOS Cisco router?

ip route 0.0.0.0 0.0.0.0 destination address

 

98. What is the difference between a domain local group and a global group?

Domain local groups grant permissions to objects within the domain in which the reside. Global groups contain grant permissions tree or forest wide for any objects within the Active Directory.

 

99. What is LDAP used for?

LDAP is a set of protocol used for providing access to information directories.

 

100. What tool have you used to create and analyze packet captures?

Network Monitor in Win2K / Win2K3, Ethereal in Linux, OptiView Series II (by Fluke Networks).

 

101. How does HSRP work?

If one router goes down, a backup router takes over the routing functions of the primary one.

 

102. What is the significance of the IP address 255.255.255.255?

The limited broadcast address is utilized when an IP node must perform a one-to-everyone delivery on the local network but the network ID is unknown.

 

Security interview questions for network admin

1. What is a firewall?

Firewalls are of two types:
-Hardware Firewall
-Software Firewall.
Firewall in simple manner is bascially the utility to provide the security over the network.

 

2. Describe, generally, how to manage a firewall

 

3. What is a Denial of Service attack?

Attempt to make a computer resource unavailable to its intended users

 

4. What is a “spoofed” packet?

Creation of IP packets with a forged (spoofed) source IP address

 

5. What is a SYN Flood?

The attacker (Mallet) sends several packets but does not send the "ACK" back to the server

 

6. What do you do if you are a victim of DoS?

Having a separate emergency block of IP addresses for critical servers with a separate route can be invaluable and change IP.

 

7. What is GPG/PGP?

 

8. What is SSH?

Secure shell

 

9. What is SSL? How do you create certificates?

Secure Sockets Layer

10. What would you do if you discovered a Windows system on your network has been compromised?

Update antivirus and system patch that is update of window

 

11. What is DNS Hijacking?

Hijacking the resolution of DNS names to IP addresses by the use of rogue DNS servers, particularly for the practice of phishing

 

12. What is a log host?

A designated device for receiving and storing a record of events from another device or program

 

13. What is IDS or IPS, and can you give me an example of one?

Intrusion-detection systems (IDS), intrusion-prevention systems (IPS)

FIREWALL, Microsoft ISA 2000/2003, Cisco IOS, checkpoint

 

14. Why are proxy servers useful?

To hide real IP of sever

 

15. What is web-caching?

By retrieving content saved from a previous request, made by the same client or even other clients

 

Cisco-specific network engineer questions

 

1. What is a wildcard mask, and how is it different from a netmask?

wildcard mask A 32-bit quantity used in conjunction with an IP address to determine which bits in an IP address should be ignored when comparing that address with another IP address. A wildcard mask is specified when setting up access lists.

The difference is wildcard mask is used in ACL, OSPF etc.,where has net mask is the mask use to define ip addressing

 

2. How do you configure a Cisco switch or router? What are the steps needed?

 

3. How would I place an interface into trunking mode?

Catalyst_4000(config)# int fa0/1


Catalyst_4000(config-if)# switchport mode trunk


Catalyst_4000(config-if)# exit


 


4. How do you shutdown an interface on a router or switch?



Router(config) # int s 0/0



Router(config-if)#shut



 



5. What is VTP?



VLAN Trunking Protocol (VTP) is a Cisco Layer 2 messaging protocol that manages the addition, deletion, and renaming of VLANs



 



6. What is VMPS?



VLAN Membership Policy Server



 



7. What is SPAN/RSPAN?



Switched Port Analyzer (SPAN) and Remote SPAN (RSPAN)



SPAN/RSPAN allows you to duplicate traffic from a VLAN or a range of ports on a Catalyst switch to another port, where you can plug a network analyzer and tools like Netflow Simulator. RSPAN stands for Remote SPAN and allows to duplicate traffic from a switch and to send it to another switch in your network.



What is flow/netflow?



NetFlow is an open but proprietary network protocol developed by Cisco Systems to run on Cisco IOS-enabled equipment for collecting IP traffic information.



 



8. What is TACACS? Radius?



TACACS and Radius are AAA server



RADIUS uses UDP while TACACS+ uses TCP, Radius is open standard where TACACS is cisco proprietary



 



Network engineer interview questions



 





OSPF


 





1. Describe OSPF in your own words.



o Ospf stand for open shortest path first



o OSPF use a link-state in the individual areas that make up the hierarchy. A computation based on Dijkstra's algorithm is used to calculate the shortest path tree inside



2. OSPF areas, the purpose of having each of them



o logical groupings of routers whose information may be summarized towards the rest of the network



o Backbone area



The backbone area (also known as area zero or area 0.0.0.0) forms the core of an OSPF network. All other areas are connected to it, and inter-area routing happens via routers connected to the backbone area and to their own non-backbone areas. It is the logical and physical structure for the 'OSPF domain' and is attached to all nonzero areas in the OSPF domain. Note that in OSPF the term Autonomous System Border Router (ASBR) is historic, in the sense that many OSPF domains can coexist in the same Internet-visible autonomous system



The backone area is resposible for distributing routing information beetween non backbone areas. The backbone must be contiguous,but it does not need to be physically contiguous; backbone connectivity can be established and maintained through the configuration of virtual links



o Stub area



· A stub area is an area which does not receive external routes except the default route, but does receive inter-area routes. This kind of area is useful when, for example, all Internet access goes through autonomous system border routers (ASBRs) [Note: ASBR is an ancient term as written in the "Backbone area" section!] in Area 0.0.0.0, but there are multiple paths to other nonzero areas in the OSPF domain.



· All routers in the area need to agree they are stub, so that they do not generate types of LSA not appropriate to a stub area. The Type 3 LSA for the default route is the only external that should enter the area, and none of its routers may generate externals.



· Stub areas do receive inter-area (IA) routes, advertised with Type 3 and Type 4 LSAs. If the stub area has more than one area border router (ABR), the information on other non-backbone areas allows the routers in the stub area to pick the best route to another area.



· Stub areas do not have the transit attribute and thus cannot be traversed by a virtual link.



· Stub areas receive default routes as type 3 network summary LSAs



Totally stubby area



· A totally stubby area (TSA), which is a nonstandard but useful extension by Cisco , is similar to a stub area, however this area does not allow summary routes in addition to the external routes, that is, inter-area (IA) routes are not summarized into totally stubby areas. The only way for traffic to get routed outside of the area is a default route which is the only Type-3 LSA advertised into the area. When there is only one route out of the area, fewer routing decisions have to be made by the route processor, which lowers system resource utilization.



· Occasionally, it is said that a TSA can have only one ABR. This is not true. If there are multiple ABRs, as might be required for high availability, routers interior to the TSA will send non-intra-area traffic to the ABR with the lowest intra-area metric (the "closest" ABR).



· An area can simultaneously be not-so-stubby and totally stubby. This is done when the practical place to put an ASBR, as, for example, with a newly acquired subsidiary, is on the edge of a totally stubby area. In such a case, the ASBR does send externals into the totally stubby area, and they are available to OSPF speakers within that area. In Cisco's implementation, the external routes can be summarized before injecting them into the totally stubby area. In general, the ASBR should not advertise default into the TSA-NSSA, although this can work with extremely careful design and operation, for the limited special cases in which such an advertisement makes sense.



· By declaring the totally stubby area as NSSA, no external routes from the backbone, except the default route, enter the area being discussed. The externals do reach area 0.0.0.0 via the TSA-NSSA, but no routes other than the default route enter the TSA-NSSA. Routers in the TSA-NSSA send all traffic to the ABR, except to routes advertised by the ASBR.



Not-so-stubby area



· Not-so-stubby area (NSSA) is a type of stub area that can import autonomous system (AS) external routes and send them to the backbone, but cannot receive AS external routes from the backbone or other areas. The NSSA is a non-proprietary extension of the existing stub area feature that allows the injection of external routes in a limited fashion into the stub area.



· Cisco also implements a proprietary version of a NSSA called a NSSA totally stubby area. It takes on the attributes of a TSA, meaning that type 3 and type 4 summary routes are not flooded into this type of area. It is also possible to declare an area both totally stubby and not-so-stubby, which means that the area will receive only the default route from area 0.0.0.0, but can also contain an autonomous system border router (ASBR) that accepts external routing information and injects it into the local area, and from the local area into area 0.0.0.0.



· Redistribution into an NSSA area creates special type of LSA known as TYPE 7, which can exist only in an NSSA area. An NSSA ASBR generates this LSA, and an NSSA ABR router translates it into type 5 LSA which gets propagated into the OSPF domain.



Transit Areas



Transit areas are used to pass traffic from one adjacent area to the backbone (or to another area if the backbone is more than two hops away from an area). The traffic does not originate in, nor is it destined for, the transit area.



3. Types of OSPF LSA, the purpose of each LSA type



1. Router LSA



2. Network LSA



3. Summary LSA (IP Network)



4. Summary LSA (Autonomous System Boundary Router)



5. Autonomous System External LSA



Type 1: Router link advertisements generated by each router for each area it belongs to. Flooded to a single area only.


Type 2: Network link advertisements generated by designated routers describing the set of routers attached to a particular network. Flooded to the area that contains the network.


Type 3/4: Summary link advertisements generated by ABRs

describing inter-area routes. Type 3 describes routes to networks and is used for summarization. Type 4 describes routes to the ASBR.


Type 5: Generated by the ASBR and describes links external


to the Autonomous System (AS). Flooded to all areas except stub areas.




Type 6: Group membership link entry generated by multicast OSPF routers.




Type 7: NSSA external routes generated by ASBR. Only flooded to the NSSA. The ABR converts LSA type 7 into LSA type 5 before flooding them into the backbone (area 0).











 



2. What exact LSA type you can see in different areas



 



3. How OSPF establishes neighbor relation, what the stages are



INIT, Ex-start, Ex-change, Loading, Full



 



4. If OSPF router is stacked in each stage what the problem is and how to troubleshoot it



 



5. OSPF hierarchy in the single or multi areas. Cool OSPF behavior in broadcast and no broadcast



Multi area



6. Draw the diagram of typical OSPF network and explain generally how it works, DR, BDR, election, ASBR, ABR, route redistribution and summarization



 





STP




1. How it works and the purpose



o prevent switching loops in the LAN



o Spanning Tree works by first using an algorithm to find redundant links in the LAN and selecting the best paths. Its initial goal is to put all links in either Forwarding or Blocking.



 



2. Diff types (SSTP, MSTP, RSTP) Cisco - PVST/PVST+



 



3. root election



 



4. Diff. port stages and timing for convergence



 



5. Draw the typical diagram and explain how diff types of STP work



 



6. What ports are blocking or forwarding



 



7. How it works if there are topology changes



 


 


ACLs




1. What are they?



Filter defined by administrator



 



2. Diff types of acl



Standard, extended, Named acl



 



3. Write an example if you want to allow and to deny…



Access-list 101 Permit tcp any 192.168.44.252 0.0.0.0 eq 21



Access-list 101 deny tcp any 192.168.44.252 0.0.0.0 eq 80



 



4. Well-known port numbers (DNS - 53 and etc…)



HTTP 80



HTTPS 443 TCP



Pop3 110 TCP



NTP 123 UDP



SNMP 161 UPD



 


 


QoS quality of service





 



1. What is QoS



In the field of computer networking and other packet-switched telecommunication networks, the traffic engineering term quality of service (QoS) refers to resource reservation control mechanisms rather than the achieved service quality



Guarantee a certain level of performance to a data flow



 



2. What is the diff b/w L2 and L3 QoS



o pure L2 QoS mechanisms, e.g., VP/VC based for ATM networks, DLCI based for FR networks, or VLAN tag for Ethernet



o intermediate L2/L3 QoS mechanisms, e.g., MPLS



o pure L3 QoS mechanisms, e.g., DiffServ



o L3 over L2 QoS mechanisms, e.g., DiffServ over ATM or FR



o L3 over intermediate L2/L3, e.g., DiffServ and MPLS seamless integration



 



How it works



 


Switching




1. VLANs



2. STP



3. How a L2 switch works with broadcast, unicast, multicast, known/unknown traffic



4. VRRP, GLBP



5. port monitoring and mirroring



6. L3 switch, how it works



7. PIM sparse and dense modes



 



Wireless engineer interview questions



 





A recruiter from Atlanta submitted this set of questions for interviewing at a wireless equipment company.



1. Describe your home WLAN setup.



(Pay attention to candidate’s confidence. Plus if the candidate built it himself. Plus if the network is secured additionally, regardless of the protocols used. Plus if the candidate fought poor coverage.)



2. Ad-hoc vs. infrastructure topology. Advantages and disadvantages.



Ad-hoc networks are easy to set up. By definition ad-hoc WLANs do not require access point, so they are cheaper. With infrastructure WLANs one can connect to wired LAN, enable wireless roaming for office workers, centralize WLAN management, and boost the range.



3. Your preferred brand for wireless cards and access points.



(An experienced candidate will be able to come up with strong argument to defend his preferences. He will point to the past projects as well.)



4. Range and throughput of 802.11a, 802.11b and 802.11g networks.



The official spec for 802.11a is 54 Mbps and 25-75 feet indoors.



The official spec for 802.11b is 11 Mbps and 100-150 feet indoors.



The official spec for 802.11g is 54 Mbps and 100-150 feet indoors.



An experienced candidate will provide his own observations.



5. How do you secure a wireless network?



Forbid SSID broadcasting,



Enable MAC-level access where appropriate,



Enable WEP, OR enable WPA



Enable 802.11i where available,



Enable firewalls,



.



6. What does Wi-Fi stand for?



Wireless Fidelity.



7. What is 802.11i?



It’s a new IEEE standard defining wireless network security.



8. What are the recommended channels if you’re setting up three WLANs and want minimum interference?



1, 6 and 11 for the US, 1, 7 and 13 for Europe and 1, 7 and 14 for Japan.



9. What are your preferred tools for war-driving?



Somewhere the names Kismet, *stumbler or others should come up. Ask the

candidate to describe his preferred configuration for war-driving.



 



Network engineer/architect interview questions



 



1. Explain how traceroute, ping, and tcpdump work and what they are used for?



Traceroute;


 


Traceroute works by increasing the "time-to-live" value of each successive batch of packets sent. The first three packets sent have a time-to-live (TTL) value of one (implying that they are not forwarded by the next router and make only a single hop). The next three packets have a TTL value of 2, and so on. When a packet passes through a host, normally the host decrements the TTL value by one, and forwards the packet to the next host. When a packet with a


TTL of one reaches a host, the host discards the packet and sends an ICMP time exceeded (type 11) packet to the sender. The traceroute utility uses these returning packets to produce a list of hosts that the packets have traversed en route to the destination. The three timestamp values returned for each host along the path are the delay (aka latency) values typically in milliseconds (ms) for each packet in the batch. If a packet does not return within the expected timeout window, a star (asterisk) is traditionally printed. Traceroute may not list the real hosts. It indicates that the first host is at one hop, the second host at two hops, etc. IP does not guarantee that all the packets take the same route. Also note that if the host at hop number N does not reply, the hop will be skipped in the output.


 


Ping:


 


It works by sending ICMP “echo request” packets to the target host and listening for ICMP “echo response” replies. Ping estimates the round-trip time, generally in milliseconds, and records any packet loss, and prints a statistical summary when finished.


 



2. Describe a case where you have used these tools to troubleshoot.



Explain your experience



 



3. What is the last major networking problem you troubleshot and solved on your own in the last year?



Explain your practical life problem u had which you consider was important achievement



 



4. What LAN analyzer tools are you familiar with and describe how you use them to troubleshoot and on what media and network types.



MGRT, PGRT, WIRE SHARK (formally ethereal) for bandwidth monitoring and server monitoring



 



5. Explain the contents of a routing table (default route, next hop, etc.)



 



6. What routing protocols have you configured?



Most of time static route we use in our wireless network, but I m very familiar with OSPF



 



7. Describe the commands to set up a route.



Ip route (source network) (destination network) interface



 



8. What routing problems have you troubleshot?



 



9. How do you display a routing table on a Cisco? On a host?



Sh cdp neighbor detail



Sh ip route (local)



 



10. How do you use a routing table and for what?



For troubleshooting and searching for route to destination



 



11. What is a route flap?



o Route flapping occurs when a router alternately advertises a destination network via one route then another (or as unavailable, and then available again) in quick sequence.



o Route flapping is caused by pathological conditions (hardware errors, software errors, configuration errors, unreliable connections, etc.) within the network which cause certain reachability information to be repeatedly advertised and withdrawn. The most common causes of route flapping are configuration errors and intermittent errors in communications links. Route flapping often forces a router to recalculate a new or preferred route to a particular network, while traffic destined for that network is in transit through the router.



 



12. What is a metric?



Metric is a measure used in calculating the next host to route a packet to.



 



13. When do you use BGP, IGRP, OSPF, and Static Routes?



· BGP - Boarder Gateway protocol



Use for communicating different Ad number, and use in very large network like internet for route maintaining



· IGRP - Interior Gateway Routing Protocol



IGRP is dynamic routing protocol and use for routing in large flat network. (All Cisco Device only)



· OSPF - Open Shortest Path First



OSPF is dynamic routing protocol and use for routing in large hierarchical network. And it is open standard.



· Static Route use for maintaining manual routes and point-to-point communication



 



14. What do you see as current networking security issues (e.g. NFS mounting, spoofing, one time passwords, etc.)?



One time password, wireless security



 



15. Describe a routing filter and what it does.



 



16. Describe an access list and what it does.



 



17. What is a network management system?





Network Management System - A comprehensive system of equipment used in monitoring, controlling, and managing a data communications network. Usually consists of testing devices, CRT displays and printers, patch panels, and circuitry for diagnostics and reconfiguration of channels, generally housed together in an operator console unit.



 



18. Describe how SNMP works.



The simple network management protocol (SNMP) use for monitoring of network-attached devices for any conditions that warrant administrative attention. It is use to manage IP network devices such as servers, routers, switches etc. Administrator can find or manage network performance, solve problem or even optimize it further. It works at TCP/IP Application layer 5 (L5).



 



19. Describe the working environment you are currently in, e.g. frequent interruptions, frequent priority shifting, team or individual.



 



20. What do you use to write documentation? Editor? Mail reader?



 



21. What platform (s) do you currently work on at your desk?



Window XP



 



22. How do you manage multiple concurrent high level projects?



Time and team management



 



23. Describe a recent short term stressful situation and how you managed it.



When I was working for base station and same time shifting of NOC



 



24. How do you manage a long term demanding stressful work environment?



By time management, I always keep my work at work place and home at home I m able to manage both place



 



25. Have you worked in an assignment based environment, e.g. work request/trouble ticket system, and if so, describe that environment.



 



26. Describe what network statistics or measurement tools you are familiar with and how you have used them.



PGRT, MGRT, WHATSUP GOLD,



 



27. Describe what a VPN is and how it works.



A VPN is a private network that uses a public network (usually the Internet) to connect remote sites or users together. Instead of using a dedicated, real-world connection such as leased line



 



28. Describe how VoIP works.



Voice over IP, or VoIP, means that your voice is carried over the IP network, otherwise known as the Internet. Your voice, which is an analogue signal, is converted to digital data, which is then disassembled and transmitted through the Internet only to be re-converted back to an analogue signal on the other end.



Protocols used to carry voice signals over the IP network are commonly referred to as Voice over IP or VoIP protocols.



 



29. Describe methods of QoS.



clip_image002First-in, first-out (FIFO) queuing



clip_image002[1]Priority queuing (PQ)



clip_image002[2]Custom queuing (CQ)



clip_image002[3]Flow-based weighted fair queuing (WFQ)



clip_image002[4]Class-based weighted fair queuing (CBWFQ)



 



30. How does ToS bit work?



The Type of Service (ToS) field in the IP header constitutes the bits used for IP precedence. These bits are used to provide a priority from 0 to 7



 



RF and radio engineering interview questions



 



1. What’s a PCB?



Printed Circuit Board.



 



2. Name some band definitions.



L-Band - 1-2 GHz, S-Band - 2-4 GHz, C-Band - 4-8 GHz, X-Band - 8-12 GHz, Ku-Band - 12-18 GHz.



 



3. What’s the definition of gain?



The signal going into the device is smaller than the signal going out.



 



4. What’s a definition of an amplifier?



It’s a device that exhibits gain.



 



5. Insertion loss?



The signal going in is greater than the signal that’s coming out.



 



6. Thermal impedance?



A measure of how hot the device gets with varying electrical input.



 



7. What’s the relation between dB and change of signal?



+3 dB is 2 times bigger, +10 dB is 10 times bigger.



 



8. What’s an octave?



The bandwidth characterized by higher band being twice as much as lower band (100-200 MHz).



 



9. What’s a decade?



A bandwidth, where the higher band is 10x the lower band (100 MHz - 1 GHz).



 



10. Skin effect?



The signal is reported on the surface of the object, but not inside, e.g. a solid brick wall.



 



11. VSWR?



Voltage Standing Wave Ratio. The numeric representation of the device leak, written like X: 1 where X is greater when the leak is greater and 1:1 is the absolute no-leakage VSWR.



 



12. Describe an impedance matching circuit.



A circuit capable of changing the impedance with different values for incoming and outgoing impedance.



 



13. Describe circular polarization.



The signal travels both vertically and horizontally.



 



14. What’s the job of the amplifier?



To increase the incoming signal.



 



15. What is noise figure?



The level of noise that a low-noise amplifier (LNA) is capable of discriminating.



 



16. What’s a transfer curve?



It is a graph of the output power versus the input power of an amplifier.



 



17. What’s the 911 point?



The point where the input power results in flames on the other end.



 



18. What’s saturation point?



The point where the amplifier loses its linearity of the transfer curve.



 



19. What does balanced amplifier consist of?



Two amplifiers stuck together.



 



20. What is the filters function?



To filter out all the unwanted radio signals.



 



21. What filter types are there?



Low-pass (all frequencies below are allowed to pass in), high-pass, bandpass (all frequencies of a given bandwidth are allowed) and band-reject.



 



22. What are saw filters used for?



Very low frequency filtering.



 



23. What are mixers used for?



To change the frequency of the signal.



 



24. What’s a superheterodyne receiver?



It’s a receiver that uses two mixers in a row.



 



25. Describe VCO.



Voltage-controlled oscillators change the frequency of the produced sine wave depending on the voltage they receive.



 



26. Who is responsible for PLLs?



Phase-locked loops are done by synthesizer that samples the sine wave and if it’s not good enough, changes it.