NETGEAR 108 MBPS WIRELESS WGT624 V3 - Manual (Page 37)

Reference Manual for the 108 Mbps Wireless Firewall Router WGT624 v3
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202-10090-02 v 1.4, July 2005
Services are functions performed by server computers at the request of client computers. For
example, web servers serve web pages, time servers serve time and date information, and game
hosts serve data about other players’ moves. When a computer on your network sends a request for
service to a server computer on the Internet, the requested service is identified by a service or port
number. This number appears as the destination port number in the transmitted IP packets. For
example, a packet that is sent with destination port number 80 is an HTTP (web server) request.
To enable service blocking, select either Per Schedule or Always, then click Apply. If you want to
block by schedule, be sure that a time period is specified in the Schedule menu.
To specify a service for blocking, click Add. The Add Services menu will appear, as shown below:
Figure 4-3: Add Services menu
From the Service Type list, select the application or service to be allowed or blocked. The list
already displays several common services, but you are not limited to these choices. To add any
additional services or applications that do not already appear, select User Defined.
• Configuring a User Defined Service
To define a service, first you must determine which port number or range of numbers is used by
the application. The service numbers for many common protocols are defined by the Internet
Engineering Task Force (IETF) and published in RFC1700, “Assigned Numbers.” Service
numbers for other applications are typically chosen from the range 1024 to 65535 by the authors of
the application. This information can usually be determined by contacting the publisher of the
application or from user groups of newsgroups.