Secure Telnet Using Ssh Examples; Figure 7-3 How Ssh Works - ZyXEL Communications Vantage RADIUS 50 User Manual

Vantage RADIUS User's Guide
7.3.1 How SSH works
The following table summarizes how a secure connection is established between two remote hosts.

Figure 7-3 How SSH Works

7.3.2 Requirements for Using SSH
You must install an SSH client program on a client computer (Windows or Linux operating system) that is
used to connect to Vantage RADIUS over SSH.
7.4

Secure Telnet Using SSH Examples

This section shows two examples using a command interface and a graphical interface SSH client program
to remotely access Vantage RADIUS. The configuration and connection steps are similar for most SSH
client programs. Refer to your SSH client program user's guide.
7-4
1. Host Identification
The SSH client sends a connection request to the
SSH server. The server identifies itself with a host
key. The client encrypts a randomly generated
session key with the host key and server key and
sends the result back to the server.
The client automatically saves any new server
public keys. In subsequent connections, the server
public key is checked against the saved version on
the client computer.
2. Encryption Method
Once the identification is verified, both the client and
server must agree on the type of encryption method
to use.
3. Authentication and Data Transmission
After the identification is verified and data encryption
activated, a secure tunnel is established between
the client and the server. The client then sends its
authentication information (user name and
password) to the server to log in to the server.
Management