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Showing posts from June, 2007

Practical Uses of Netstat Command in Analyzing Connected Foreign Addresses

Netstat command is a DOS command used to find all active TCP connections between your computer and other network devices with port numbers and TCP connection state. By simply using this command on the command prompt, you will get the list of active TCP connections between local IP address(your computer) and foreign IP addresses. You can also find the port numbers open in those connections. With proper syntax, we can effectively use it to view how your computer is connected to foreign computers. It has many important uses in computer security. Check the image below to understand its simple use. List of Common Netstat Command Syntax netstat -n: Displays addresses and port numbers in numerical form netstat -a: Displays all connections and listening ports netstat -b: Displays the executable involved in creating each connection or listening ports. netstat -e: Displays Ethernet statistics netstat -o: Displays the Process Identifier associated with each connection netst

Tracert- Tool to Find the Path of a Packet

Tracert command is used to determine the path from your computer to the destination host by sending ICMP Echo Request messages. The path through which the packet traveled will be printed in the command prompt. ICMP command Tracert is very helpful to troubleshoot any kind of network related issues. It is used to determine the network location where the actual cause of the issue present in any kind of network related issues. It sends ICMP Echo messages to the destination host and decrements its TTL value by one when it passes on each hop. When the packets pass each hop it displays the path in DOS window and you can easily identify the route. This feature helps to identify the actual cause of any network issue. So it is a handy tool for every network Engineers to analyze and troubleshoot network issues. Let us check how to use this tool. If you want to know the route of the server of from your computer, you can check it by typing following code on DOS prompt. T

Create Or Delete Windows User Account From Command Prompt

You can create a user account on your computer directly from Command Prompt by using the DOS command Net User . This command not only helps to create a new user account on a Windows computer but also helps to modify an existing user account. This tutorial explains the use of the command net user and explains the procedure to create a new user account on a Windows computer. We also check how to modify an existing user account on a Windows computer using net user command. Learn The Command Net user The net user command is used to create, delete and edit user accounts on Windows computers from the command prompt. Let us check different syntax to create, modify and delete user accounts from Command Prompt. To create User Account:   net user Username Password /domain To modify User Account:   net user Username Password /add /domain To Delete User Account:   net user Username /delete /domain While entering username from Command Prompt for a new user account, make sure i

Wireless Range Expander- an introduction

The function of a wireless range expander is to extend the range of the wireless signal from a wireless router. The pictorial representation of the working is given below. Wireless router--------(45 feet)----------------pc Let us think the range of the router signal is 45 feet. The wireless adapter on the pc will receive the signal from the router and will create a connection between the wireless router and the pc. If the distance between the pc and the wireless router is 70 feet what can we do? Ans. Establish a range expander in between the router and the pc. The range expander will receive the signal from the wireless router and extend the signal to a certain limit. wireless router-----(40 feet)------range extender----(30 feet)------pc( wireless adapter) Now the wireless computer will go online by receiving the signal from range expander. The detailed explanation will be in the following posts...... No: Recent Tutorials How To Power Cycle a

Session layer and Its Importance in OSI Reference Model

The session layer is the fifth layer in the OSI reference model. It responds to service requests from the Presentation layer and issues service requests to Transport layer. The major function of the Session layer is to create, maintain and terminate sessions. The session layer is also responsible for finding and sending data across the correct connection. To set up and tear down connection Session layer communicate with the Transport layer. Major functions of the Session layer are listed below. The major functions of the session layer are: Starts and ends a session across a network Allows applications to share information. Ensures that information is flowing to the right place Communicate to the presentation layer and Transport layer. We can have multiple sessions on a network due to the Session layer. Eg: We are seeing a movie where sound and the seen both should match. It is one of the applications of the Session layer. A list of protocols working in Session layer is

Role of Transport Layer - Responsibilities and Protocols

The transport layer is the fourth layer in OSI Reference Model. It responds to service requests from Session layer and issues service requests to Network layer. Transport Layer is responsible for delivering messages between hosts. In the Transport layer, data travels in the form of segments. The transport layer is responsible for creating an end to end connection between source IP and the destination IP. For establishing this end to end connection, the Transport layer is using two major protocols TCP and UDP. TCP is connection oriented protocol where UDP is connectionless protocol. So by using TCP, we can create an end to end reliable connection between the source and destination hosts. The transport layer is called the host-to-host transport layer in the TCP/IP model. Duties of  The Transport Layer Major duties of the Transport layer are: Creating an end-to-end connection between hosts in different networks, Error recovery, Flow control, Ensuring complete da

MAC Sublayer Defined in IEEE 802.3

During the development of IEEE Ethernet, IEEE divided Data Link layer into two. They are MAC sublayer and LLC sublayer. MAC sublayer functions are performed in hardware and are the bottom part of the data link layer. MAC sublayer is defined in IEEE 802.3. MAC sublayer defines how data is transmitted in an Ethernet environment and defines framing, MAC address, etc. Let us check the functions of MAC sublayer in the details below. Major Functions of MAC Sublayer in IEEE Ethernet Defines how information is transmitted in an Ethernet environment MAC Sublayer defines framing This Sublayer defines the working of Ethernet and MAC addressing CSMA/CD works in MAC Sublayer How to Differentiate Ethernet II and MAC Sublayer Frames We know Ethernet has two versions and it is important to know how to differentiate both versions of Ethernet. The major difference between Ethernet II (developed by DIX) and IEEE 802.2/3 is the frame value. If the frame value is greater than 1500, t

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Alex George
Alex George has Engineering graduation in Computer Science and an MBA in Finance. He had been working as a senior Network Engineer for ten years. His specialization is in Cisco products. Traveling is one of his hobbies and visited various places as part of his onsite work. He visited different places as part of his onsite work like New York, Dubai, London, etc. Right now Alex is a director of one of the leading career development firms in India, which trains students for UPSC, SSC, and PSC examinations. He guides a lot of students to get selection for various prestigious institutions like CBI, Income Tax Department, etc. Alex George is a stock market investor and a very active intraday trader. Engineering Background: He has a B.Tech in Computer Science and Engineering and passed different network and security courses like CCNA, CCNP (Security), CEH, and various Microsoft certifications. Finance Background: Alex has an MBA in Finance. He is an active intraday trader and a Share Market Investor. Webmaster Skills: Alex is a blogger since 2004. He has a working knowledge of HTML, CSS, PHP, and JavaScrip.