ZyXEL Communications ZyWALL 300 User Manual

Chapter 44 Service Control

ZyWALL USG 300 User’s Guide

You can use SSH (Secure SHell) to securely access the ZyWALL’s command line interface. 
Specify which zones allow SSH access and from which IP address the access can come. 

SSH is a secure communication protocol that combines authentication and data encryption to 
provide secure encrypted communication between two hosts over an unsecured network. In 
the following figure, computer A on the Internet uses SSH to securely connect to the WAN 
port of the ZyWALL for a management session.

Figure 445   SSH Communication Over the WAN Example

The following figure is an example of how a secure connection is established between two 
remote hosts using SSH v1.

Figure 446   How SSH v1 Works Example

1 Host Identification