Perhaps no command line utility is more familiar to users than PING. On a TCP/IP network, the PING utility allows you to determine whether another system is reachable, while at the same time providing basic diagnostic information such as whether any packets are being lost en route. When troubleshooting a network connection, PING is almost […]

If you’re connected to a TCP/IP network, the IPCONFIG utility is one that you need to be familiar with. Most users are familiar with the tool from using it to renew an IP address allocated by a DHCP server via the /renew switch. However, IPCONFIG provides a wealth of useful information about your system’s TCP/IP […]

If your computer has an Ethernet or Wi-Fi network adapter card installed and is connected to a TCP/IP network, the Address Resolution Protocol is used to map IP addresses of systems you are communicating with on the local network to their network card’s physical MAC address. The ARP command allows you to view the MAC […]

Certainly you don’t need to know anything about port numbers if you never plan to allow external users to access your network, or if you don’t plan to control the types of Internet services that your internal users can use. However, if you do plan to make use of either feature, you’ll need to know […]

If you’ve ever tried your hand at configuring a home network, chances as good that you’ve run into communications problems at some point. All Windows versions include a variety of network diagnostic tools, although you’ll find more in Windows XP than Windows 98. Regardless of your operating system version, the two basic tools that you’ll […]

Once TCP/IP is installed and configured on the computers on your network, a variety of helpful and interesting diagnostic and troubleshooting utilities become available to you. Most of these utilities are meant to be run from the command line, so make sure that you have that command prompt icon nice and handy on your desktop. […]

Assuming that you do plan to use your home network to share an Internet connection, one addition piece of information that you’ll need to supply as part of the TCP/IP configuration of computers is the IP address of one or more DNS servers. DNS is the domain name system, which is responsible for translating fully […]

When configuring TCP/IP settings on your home network, only an IP address and subnet mask are explicitly required. However, if you want your computers to be able to communicate with outside networks (like the Internet), you will also need to configure a default gateway IP address. The default gateway is the IP address to which […]

Subnet masks are easily one of the most confusing elements in the configuration of TCP/IP, although they need not be. In large, complex networks, subnet masks like 255.255.255.0 are used to segment IP addresses from one large network into many smaller ones. For example, a large corporate might be assigned a range of IP addresses […]

In the same way that you can’t just randomly choose the numbers to use for an IP address, you also need to be careful with the addresses you ultimately use. IP addresses used on the public Internet are assigned to companies from organizations like RIPE (the European IP address registry), or from an ISP. Although […]