P-661H/HW Series User’s Guide

Table 65 Predefined Services (continued)

SERVICE

DESCRIPTION

 

 

SSDP(UDP:1900)

Simole Service Discovery Protocol (SSDP) is a discovery service

 

searching for Universal Plug and Play devices on your home network

 

or upstream Internet gateways using DUDP port 1900.

SSH(TCP/UDP:22)

Secure Shell Remote Login Program.

 

 

STRMWORKS(UDP:1558)

Stream Works Protocol.

 

 

SYSLOG(UDP:514)

Syslog allows you to send system logs to a UNIX server.

 

 

TACACS(UDP:49)

Login Host Protocol used for (Terminal Access Controller Access

 

Control System).

TELNET(TCP:23)

Telnet is the login and terminal emulation protocol common on the

 

Internet and in UNIX environments. It operates over TCP/IP networks.

 

Its primary function is to allow users to log into remote host systems.

TFTP(UDP:69)

Trivial File Transfer Protocol is an Internet file transfer protocol similar

 

to FTP, but uses the UDP (User Datagram Protocol) rather than TCP

 

(Transmission Control Protocol).

VDOLIVE(TCP:7000)

Another videoconferencing solution.

 

 

9.10 Anti-Probing

If an outside user attempts to probe an unsupported port on your ZyXEL Device, an ICMP response packet is automatically returned. This allows the outside user to know the ZyXEL Device exists. The ZyXEL Device supports anti-probing, which prevents the ICMP response packet from being sent. This keeps outsiders from discovering your ZyXEL Device when unsupported ports are probed.

Internet Control Message Protocol (ICMP) is a message control and error-reporting protocol between a host server and a gateway to the Internet. ICMP uses Internet Protocol (IP) datagrams, but the messages are processed by the TCP/IP software and directly apparent to the application user.

Refer to Section 8.1 on page 145 for more information.

Click Security > Firewall > Anti Probing to display the screen as shown.

Figure 96 Firewall: Anti Probing

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Chapter 9 Firewall Configuration