3Com Webcache 3000 (3C16116), Webcache 1000 (3C16115) manual Host Name

Network Configuration Concepts 47

exists on your network, enter the IP address 0.0.0.0 or leave the field blank.

If you set the default router to 0.0.0.0 or leave it blank, the Webcache will only be able to access devices that are in the same subnet as the Webcache.

Domain Name System The Domain Name System (DNS) maps a numerical Internet Protocol (IP) address to a more meaningful and easy-to-remember name. When you need to access another device on your network, you enter the name of the device, instead of its IP address. A Domain Name System server on your network is contacted and asked the electronic form of the question, “What is the IP address of the destination device?”. The DNS server is a machine that keeps track of all the names and their equivalent numeric IP addresses. The DNS server responds with the correct IP address (e.g. 128.118.2.23), allowing the two devices to communicate with each other.

To enable the Domain Name System, you must setup a DNS server on your network. If you are uncertain about how to do this, contact your network administrator.

The following Webcache features are only available if you have setup a

DNS server:

■Access to the Webcache by DNS Name — You can access the Web interface or Command Line Interface of the Webcache via its DNS name, rather than its IP address e.g. webcache.mycompany.com.

■Web Proxy Auto-Discovery— This protocol can be used to configure Web browsers on client machines in a Proxy Cache deployment. For further information, see “Web Proxy Auto-Discovery (WPAD)” on page 53.

Domain Name System You must use the following syntax for the Domain Name System host Syntax name and domain name:

■Host Name

■The host name must be at least 1 character long.

■The host name must not exceed 63 characters long.

■The host name must be comprised of alphanumeric characters, - (hyphens) and _ (underscores).