
Appendix D Common Services
ZyWALL 2 Plus User’s Guide
654
Table 238 Commonly Used Services
NAME PROTOCOL PORT(S) DESCRIPTION
AH
(IPSEC_TUNNEL)
User-Defined 51 The IPSEC AH (Authentication Header)
tunneling protocol uses this service.
AIM/New-ICQ TCP 5190 AOL’s Internet Messenger service. It is also
used as a listening port by ICQ.
AUTH TCP 113 Authentication protocol used by some
servers.
BGP TCP 179 Border Gateway Protocol.
BOOTP_CLIENT UDP 68 DHCP Client.
BOOTP_SERVER UDP 67 DHCP Server.
CU-SEEME TCP
UDP
7648
24032
A popular videoconferencing solution from
White Pines Software.
DNS TCP/UDP 53 Domain Name Server, a service that
matches web names (e.g. www.zyxel.com
)
to IP numbers.
ESP
(IPSEC_TUNNEL)
User-Defined 50 The IPSEC ESP (Encapsulation Security
Protocol) tunneling protocol uses this
service.
FINGER TCP 79 Finger is a UNIX or Internet related
command that can be used to find out if a
user is logged on.
FTP TCP
TCP
20
21
File Transfer Program, a program to enable
fast transfer of files, including large files that
may not be possible by e-mail.
H.323 TCP 1720 NetMeeting uses this protocol.
HTTP TCP 80 Hyper Text Transfer Protocol - a client/
server protocol for the world wide web.
HTTPS TCP 443 HTTPS is a secured http session often used
in e-commerce.
ICMP User-Defined 1 Internet Control Message Protocol is often
used for diagnostic or routing purposes.
ICQ UDP 4000 This is a popular Internet chat program.
IGMP (MULTICAST) User-Defined 2 Internet Group Multicast Protocol is used
when sending packets to a specific group of
hosts.
IKE UDP 500 The Internet Key Exchange algorithm is
used for key distribution and management.
IRC TCP/UDP 6667 This is another popular Internet chat
program.
MSN Messenger TCP 1863 Microsoft Networks’ messenger service
uses this protocol.
NEW-ICQ TCP 5190 An Internet chat program.
NEWS TCP 144 A protocol for news groups.
NFS UDP 2049 Network File System - NFS is a client/
server distributed file service that provides
transparent file sharing for network
environments.