TRENDnet TW-H6W1IR manual Configure NAPT for Special Applications

TW-H6W1IR ISDN Remote Router

??Port – this is a destination port number used by TCP and UDP to de-multiplex incoming IP packets.

In the above example, incoming packets with the global destination IP Address (211.11.22.3) and global destination TCP/UDP port (21) will be translated to a packet with the local destination IP Address (1.1.1.5) and local TCP/UDP port (21).

Port 21 is assigned to FTP servers. Please see Appendix C – IP Protocol and Port Numbers for more commonly assigned port numbers, or RFC 1700 for a more complete list.

Configure NAPT for Special Ap[plication]s

Some applications programs that are used over the Internet such as Microsoft NetMeeting, Diablo, CU See Me and Xwindows send information to a certain port number or within a specified range of port numbers. The exact port number used is specific to the application. However, if you find that you are having trouble using an application

92 Configuration and

Management