ZyXEL Communications Prestige 316 User Manual page 62

FTP (File Transfer Protocol)
Telnet
SMTP (Simple Mail Transfer Protocol)
DNS (Domain Name System)
HTTP (Hyper Text Transfer Protocol or WWW, Web)
POP3 (Post Office Protocol, version 3)
PPTP (Point-to-Point Tunneling Protocol)
SUA and Multiple SUA Servers
Prestige 316 Broadband Sharing Gateway / Wireless LAN
Table 4-2 Services vs. Port Number
SERVICES PORT NUMBER
21
23
25
53
80
110
1723
4-5