User manual ZYXEL P-2302HWUDL-P1

[. . . ] P-2302HWUDL-P1 Series 802. 11g Wireless VoIP Station Gateway with Built-in DECT Base Station User's Guide Version 3. 60 3/2007 Edition 2 www. zyxel. com About This User's Guide About This User's Guide Intended Audience This manual is intended for people who want to configure the ZyXEL Device using the web configurator. You should have at least a basic knowledge of TCP/IP networking concepts and topology. Related Documentation · Quick Start Guide The Quick Start Guide is designed to help you get up and running right away. It contains information on setting up your network and configuring for Internet access. [. . . ] You may enter a single port number or a range of port numbers to be forwarded, and the local IP address of the desired server. The port number identifies a service; for example, web service is on port 80 and FTP on port 21. In some cases, such as for unknown services or where one server can support more than one service (for example both FTP and web service), it might be better to specify a range of port numbers. In addition to the servers for specified services, NAT supports a default server. A service request that does not have a server explicitly designated for it is forwarded to the default server. If the default is not defined, the service request is simply discarded. For example. , let's say you want to assign ports 21-25 to one FTP, Telnet and SMTP server (A in the example), port 80 to another (B in the example) and assign a default server IP address of 192. 168. 1. 35 to a third (C in the example). You assign the LAN IP addresses and the ISP assigns the WAN IP address. The NAT network appears as a single host on the Internet. Figure 67 Multiple Servers Behind NAT Example P-2302HWUDL-P1 Series User's Guide 123 Chapter 8 NAT 8. 1. 2 Trigger Port Forwarding Some services use a dedicated range of ports on the client side and a dedicated range of ports on the server side. With regular port forwarding you set a forwarding port in NAT to forward a service (coming in from the server on the WAN) to the IP address of a computer on the client side (LAN). The problem is that port forwarding only forwards a service to a single LAN IP address. In order to use the same service on a different LAN computer, you have to manually replace the LAN computer's IP address in the forwarding port with another LAN computer's IP address, Trigger port forwarding solves this problem by allowing computers on the LAN to dynamically take turns using the service. The ZyXEL Device records the IP address of a LAN computer that sends traffic to the WAN to request a service with a specific port number and protocol (a "trigger" port). When the ZyXEL Device's WAN port receives a response with a specific port number and protocol ("incoming" port), the ZyXEL Device forwards the traffic to the LAN IP address of the computer that sent the request. After that computer's connection for that service closes, another computer on the LAN can use the service in the same manner. This way you do not need to configure a new IP address each time you want a different LAN computer to use the application. 8. 1. 2. 1 Trigger Port Forwarding Example The following is an example of trigger port forwarding. Figure 68 Trigger Port Forwarding Process: Example 1 Jane requests a file from the Real Audio server (port 7070). 2 Port 7070 is a "trigger" port and causes the ZyXEL Device to record Jane's computer IP address. The ZyXEL Device associates Jane's computer IP address with the "incoming" port range of 6970-7170. 3 The Real Audio server responds using a port number ranging between 6970-7170. 4 The ZyXEL Device forwards the traffic to Jane's computer IP address. 5 Only Jane can connect to the Real Audio server until the connection is closed or times out. [. . . ] 4 Consult the dealer or an experienced radio/TV technician for help. FCC Radiation Exposure Statement · This transmitter must not be co-located or operating in conjunction with any other antenna or transmitter. · IEEE 802. 11b or 802. 11g operation of this product in the U. S. A. · To comply with FCC RF exposure compliance requirements, a separation distance of at least 20 cm must be maintained between the antenna of this device and all persons. ! Notices Changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment. This device has been designed for the WLAN 2. 4 GHz network throughout the EC region and Switzerland, with restrictions in France. [. . . ]