Nortel Networks manual Nortel Snas 4050 clusters, Rsa Dsa

Chapter 1 Overview 39

The Nortel SNAS 4050 supports the use of three different SSH host key types:

•RSA1

•RSA

•DSA

SSH protocol version 1 always uses RSA1 keys. SSH protocol version 2 uses either RSA or DSA keys.

For management communications in the Nortel SNA solution, the Nortel

SNAS 4050 can act both as SSH server (when a user connects to the CLI using an SSH client) and as SSH client (when the Nortel SNAS 4050 initiates file or data transfers using the SCP or SFTP protocols).

For information about managing SSH keys for communication between the Nortel SNAS 4050 and the network access devices, see “Managing SSH keys using the CLI” on page 84 or “Managing SSH keys using the SREM” on page 102.

For information about managing SSH keys for Nortel SNAS 4050 management communications, see “Configuring Nortel SNAS 4050 host SSH keys using the CLI” on page 485 or “Configuring Nortel SNAS 4050 host SSH keys using the SREM” on page 548.

Nortel SNAS 4050 clusters

A cluster is a group of Nortel SNAS 4050 devices that share the same configuration parameters. Nortel Secure Network Access Switch Software Release 1.0 supports two Nortel SNAS 4050 devices, or nodes, in a cluster. A Nortel SNA network can contain multiple clusters.

Clustering offers the following benefits:

•manageability — The cluster is a single, seamless unit that automatically pushes configuration changes to its members.

•scalability — The Nortel SNAS 4050 nodes in a cluster share the burden of resource-intensive operations. The cluster distributes control of the network access devices between the Nortel SNAS 4050 nodes and distributes handling of session logon. As a result, Nortel SNAS 4050 devices in a cluster can control more switches and handle more user sessions.

Nortel Secure Network Access Switch 4050 User Guide