Computer Networking
Get flash to fully experience Pearltrees
Speed Tests
Using NSlookup.exe
Nslookup.exe is a command-line administrative tool for testing and troubleshooting DNS servers. This tool is installed along with the TCP/IP protocol through Control Panel. This article includes several tips for using Nslookup.exe. To use Nslookup.exe, please note the following: The TCP/IP protocol must be installed on the computer running Nslookup.exe At least one DNS server must be specified when you run the IPCONFIG /ALL command from a command prompt. Nslookup will always devolve the name from the current context.
Wired networks are everywhere whether you like it not. Almost every building is wired inside out, from businesses to schools to hotels. Unfortunately in most cases, little or no thought given to the physical security of the wiring.
The Passive Splice Network Tap - Home of Janitha Karunaratne
The information listed here is to assist Network Administrators in the color coding of Ethernet cables. Please be aware that modifying Ethernet cables improperly may cause loss of network connectivity. Use this information at your own risk, and insure all connectors and cables are modified in accordance with standards. The Internet Centre and its affiliates cannot be held liable for the use of this information in whole or in part.
The Internet Centre - Ethernet Cable - Color Coding Diagram
Chapter 5 Timing, Clocking, and Synchronization in the T-carrier System Time is the extension of motion. --Zeno Faster networks depend on accurate timing. As the number of bits per second increases, the time in which to look for any particular bit decreases.
T1: A Survival Guide: Chapter 5: Timing, Clocking,and Synchronization in the T-carrier System
Subnets (originated in 1985 with RFC 950) This is one of the few long, detailed explanations of subnets that you will find - so stick with it and read through it slowly.
Subnets
Simple Network Management Protocol (SNMP) is a protocol-based network management system. It is used to manage TCP/IP-based and IPX-based networks. Information on SNMP can be found in the Internet Request for Comment (RFC) 1157. Microsoft provides an SNMP agent, or client, for Windows NT and Windows 95.
Simple Network Management Protocol (SNMP) and Traps
Have you ever run in to a problem where you are attempting to troubleshoot a network connectivity issue with a network capture utility and seen only the 3 way handshake? This will happen if you are using Netmon 2.x, Netmon 3.x, Wireshark, Ethereal and most other network capture utilities. It is relatively common knowledge that this will happen when TCP Chimney offload is enabled but disabling it via the registry or netsh sometimes doesn’t always resolve the problem.
The effect of TCP Chimney offload on viewing network traffic - Microsoft Enterprise Networking Team
MIB Archive from plixer International.
This MIB Archive is freely available to help users find the SNMP information they need. Click below to download the MIB file: Cisco has a great utility for finding their MIBs on their web site. Click Here to pop up this page.
IPSec Overview Part Four: Internet Key Exchange (IKE) > IKE Overview
Internet Key Exchange (IKE) negotiates the IPSec security associations (SAs). This process requires that the IPSec systems first authenticate themselves to each other and establish ISAKMP (IKE) shared keys. A security association (SA) is a relationship between two or more entities that describes how the entities will use security services to communicate securely. In phase 1 of this process, IKE creates an authenticated, secure channel between the two IKE peers, called the IKE security association . The Diffie-Hellman key agreement is always performed in this phase.... or, even a rocket scientist can understand DNS The goal of this page is to help you make sure that your DNS is set up properly, and help you many common errors that may exist. It will also help you if you are setting up DNS for the first time -- there is a lot of valuable information in here, and after you are done, you can walk through this step-by-step to make sure you did everything properly. Just go through the following steps in order: That should cover most common errors. For a more comprehensive way to check your DNS, you may want to check out www.DNSstuff.com and www.DNSreport.com .
DNS Oversimplified: How to check your DNS
Addressing and Subnetting on the Near Side of the 'Net This document is designed to give the reader a reasonable working knowledge of TCP/IP subnetting, addressing, and routing. It is not intended to be complete, or to cover all issues.
Daryl's TCP/IP Primer
Introduction to Networking In this day and age, networks are everywhere. The Internet has also revolutionized not only the computer world, but the lives of millions in a variety of ways even in the “real world”. We tend to take for granted that computers should be connected together. In fact, these days, whenever I have two computers in the same room, I have a difficult time not connecting them together! Given the ubiquitousness of networking, it's hard to believe that the field is still a relatively young one, especially when it comes to hooking up small computers like PCs.