Test a TCP/IP configuration

To test a TCP/IP configuration by using the ping command

1. To quickly obtain the TCP/IP configuration of a computer, open Command Prompt, and then type ipconfig. From the display of the ipconfig command, ensure that the network adapter for the TCP/IP configuration you are testing is not in a Media disconnected state.
2. At the command prompt, ping the loopback address by typing ping 127.0.0.1.
3. Ping the IP address of the computer.
4. Ping the IP address of the default gateway.

   If the ping command fails, verify that the default gateway IP address is correct and that the gateway (router) is operational.

5. Ping the IP address of a remote host (a host that is on a different subnet).

   If the ping command fails, verify that the remote host IP address is correct, that the remote host is operational, and that all of the gateways (routers) between this computer and the remote host are operational.

6. Ping the IP address of the DNS server.

   If the ping command fails, verify that the DNS server IP address is correct, that the DNS server is operational, and that all of the gateways (routers) between this computer and the DNS server are operational.

Notes

• To open command prompt, click Start, point to All Programs, point to Accessories, and then click Command Prompt.
• If the ping command is not found or the command fails, you can use Event Viewer to check the System Log and look for problems reported by Setup or the Internet Protocol (TCP/IP) service.
• The ping command uses Internet Control Message Protocol (ICMP) Echo Request and Echo Reply messages. Packet filtering policies on routers, firewalls, or other types of security gateways might prevent the forwarding of this traffic.
• The ipconfig command is the command-line equivalent to the winipcfg command, which is available in Windows Millennium Edition, Windows 98, and Windows 95. Windows XP does not include a graphical equivalent to the winipcfg command; however, you can get the equivalent functionality for viewing and renewing an IP address by opening Network Connections, right-clicking a network connection, clicking Status, and then clicking the Support tab.

  Used without parameters, ipconfig displays the IP address, subnet mask, and default gateway for all adapters.

• To run ipconfig, open the command prompt, and then type ipconfig.
• To open Network Connections, click Start, click Control Panel, and then double-click Network Connections.

TCP/IP overview

Transmission Control Protocol/Internet Protocol (TCP/IP) is the most popular network protocol, and the basis for the Internet. Its routing capabilities provide maximum flexibility in an enterprise-wide network. In Windows XP TCP/IP is automatically installed.

On a TCP/IP network, you must provide IP addresses to clients. Clients may also require a naming service or a method for name resolution. This section explains IP addressing and name resolution for Network Connections on TCP/IP networks. It also describes the FTP and Telnet tools that are provided by TCP/IP.

Assigning IP addresses to dial-up and virtual private network (VPN) connections

Each remote computer connecting to a remote access server on a Windows TCP/IP network is provided an IP address by the remote access server.

If you use a specific IP address, the remote access server must be configured to permit users to request a specific address.

Name resolution for network and dial-up connections

In addition to requiring an IP address, network and dial-up connections on a TCP/IP network may require a mechanism to map computer names to IP addresses. Four name resolution options are available: DNS, WINS, broadcast name resolution, and the Hosts and Lmhosts files.

In small networks where IP addresses do not change, network and dial-up connections can use a Hosts or Lmhosts file for name resolution. By using these files on the local drive, you do not need to transmit name resolution requests to a WINS or DNS server and wait for the response.

Internet tools

TCP/IP provides File Transfer Protocol (FTP) and Telnet. FTP is a character-based utility that permits you to connect to FTP servers and transfer files. Telnet is graphical application that lets you log in to remote computers and issue commands as if you were at the keyboard of the computer. Multiple variations of FTP, Telnet, and other programs based on earlier Internet standards are also available on the Internet or commercially.

Installing Simple TCP/IP Services

To install Simple TCP/IP Services

1. Open Add or Remove Programs in Control Panel.
2. Click Add/Remove Windows Components.
3. In Components, click Networking Services, and then click Details.
4. In Subcomponents of Networking Services, click Simple TCP/IP Services, and then click OK.
5. Click Next.
6. If prompted to do so, type the path where the Windows XP distribution files are located, and then click OK.
7. Click Finish and then click Close.

Notes

• To open Add or Remove Programs, click Start, click Control Panel, and then double-click Add or Remove Programs.
• You must be logged on as an administrator or a member of the Administrators group in order to complete this procedure. If your computer is connected to a network, network policy settings may also prevent you from completing this procedure.
• Simple TCP/IP Services for Windows XP provides support for the optional TCP/IP protocol services listed in the following table.

  Protocol	Description	RFC
  Character Generator (CHARGEN)	Sends data made up of the set of 95 printable ASCII characters. Useful as a debugging tool for testing or troubleshooting line printers.	864
  Daytime	Returns messages containing the day of the week, month, day, year, current time (in hh:mm:ss format), and time-zone information. Some programs can use the output from this service for debugging or monitoring variations in system clock time or on a different host.	867
  Discard	Discards all messages received on this port without response or acknowledgment. Can serve as a null port for receiving and routing TCP/IP test messages during network setup and configuration or, in some cases, can be used by programs as a message discard function.	863
  Echo	Echoes back data from any messages it receives on this server port. Can be useful as a network debugging and monitoring tool.	862
  Quote of the Day (QUOTE)	Returns a quotation as one or more lines of text in a message. Quotations are taken at random from the following file: systemroot\System32\Drivers\Etc\Quotes. A sample quote file is installed with the Simple TCP/IP Services. If this file is missing, the quote service fails.	865

• All of these protocol services are classified as elective Internet standards and are defined and described in the specified Request for Comments (RFC) document listed in the table. For more information on these protocol services, see the RFCs.
• Do not install Simple TCP/IP Services unless you specifically need this computer to support communication with other systems that use these protocol services.
• After Simple TCP/IP Services are installed, you cannot enable or disable the separate services individually.

Configuring TCP/IP Settings

To configure TCP/IP settings

1. Open Network Connections.
2. Click the connection you want to configure, and then, under Network Tasks, click Change settings of this connection.
3. Do one of the following:
   • If the connection is a local area connection, on the General tab, under This connection uses the following items, click Internet Protocol (TCP/IP), and then click Properties.
   • If this is a dial-up, VPN, or incoming connection, click the Networking tab. In This connection uses the following items, click Internet Protocol (TCP/IP), and then click Properties.
4. Do one of the following:
   • If you want IP settings to be assigned automatically, click Obtain an IP address automatically, and then click OK.
   • If you want to specify an IP address or a DNS server address, do the following:
     • Click Use the following IP address, and in IP address, type the IP address.
     • Click Use the following DNS server addresses, and in Preferred DNS server and Alternate DNS server, type the addresses of the primary and secondary DNS servers.
5. To configure DNS, WINS, and IP Settings, click Advanced.

Notes

• To open Network Connections, click Start, click Control Panel, and then double-click Network Connections.
• You should use automated IP settings (DHCP) whenever possible, for the following reasons:
  • DHCP is enabled by default.
  • If your location changes, you do not have to modify your IP settings.
  • Automated IP settings are used for all connections, and they eliminate the need to configure settings such as DNS, WINS, and so on.