SSH Protocol (RFC 4251-4254)

1. Architecture

   Three-layer SSH architecture: transport, user authentication, connection.

2. Binary packet protocol

   Packet format, encryption and MAC.

3. Key exchange

   Algorithm negotiation and Diffie-Hellman key exchange.

4. Authentication protocol

   Authentication requests, methods and failures.

5. Public key authentication

   Public key signature authentication.

6. Connection protocol channels

   Channel mechanism, flow control and requests.

7. Session channels

   Interactive sessions, pty requests, exec and subsystems.

8. TCP/IP port forwarding

   Local and remote port forwarding requests.

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