ZyWALL 10/50 Internet Security Gateway

13.5 Predefined Services

The Available Services list box in the Rule Config(uration) screen (see Figure 13-4)displays all predefined services that the ZyWALL already supports. Next to the name of the service, two fields appear in brackets. The first field indicates the IP protocol type (TCP, UDP, or ICMP). The second field indicates the IP port number that defines the service. (Note that there may be more than one IP protocol type. For example, look at the default configuration labeled “(DNS)”. (UDP/TCP:53) means UDP port 53 and TCP port 53. Up to 128 entries are supported. Custom services may also be configured using the Custom Ports function discussed later.

 

Table 13-2 Predefined Services

 

 

SERVICE

DESCRIPTION

 

 

AIM(TCP:5190)

AOL’s Internet Messenger service, 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,

A popular videoconferencing solution from White Pines Software.

24032)

 

DNS(UDP/TCP:53)

Domain Name Server, a service that matches web names (e.g.

 

www.zyxel.com) to IP numbers.

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: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)

Net Meeting 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

ICMP service allows normal ICMP packets to go through.

ICQ(UDP:4000)

This is a popular Internet chat program.

IKE(UDP:500)

The Internet Key Exchange algorithm is used for key distribution and

 

management.

IPSEC_TUNNEL(AH:0)

The IPSEC AH (Authentication Header) tunneling protocol uses this

 

service.

Creating Custom Rules

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