Avaya ERS 8600 series, Руководство по настройке

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Figure 10: Overview of the SSH protocol
By using a combination of host, server, and session keys, the SSH protocol provides strong
authentication and secure communication over an unsecure network, offering protection from
the following security risks:
• IP spoofing
• IP source routing
• DNS spoofing
• man-in-the-middle and TCP hijacking attacks
• eavesdropping and password sniffing
Even if network security is compromised, traffic cannot be played back or decrypted, and the
connection cannot be hijacked.
The secure channel of communication provided by SSH does not provide protection against
break-in attempts or denial-of-service (DoS) attacks.
The SSH protocol supports the following security features:
• Authentication: identifies the SSH client. During logon, the SSH client is queried for a
digital proof of identity.
Supported authentications are RSA (SSH-1), DSA (SSH-2), and passwords (both SSH-1
and SSH-2).
• Encryption: scrambles data rendering it unintelligible except to the receiver.
Supported encryptions are AES and 3DES.
• Integrity: guarantees that the data is transmitted from the sender to the receiver without
alteration. If any third party captures and modifies the traffic, the SSH server detects this
alteration.
Secure Shell
Configuration — IPv6 Routing November 2010 55