Understanding SSH Authentication and Key Exchange

???? What Happens When an SSH Client Connects to a Server?

1️⃣ Key Exchange Phase (KEX)

Even if only password authentication is used, SSH still performs key exchange.

The server and client negotiate encryption keys using algorithms like Diffie-Hellman (DH).

2️⃣ User Authentication Phase

After encryption keys are exchanged, the user authenticates using a username and password.

Why is the Answer FALSE?

❌ Even with password authentication, SSH still performs key exchange to establish an encrypted session.

✅ The SSH session is always encrypted using cryptographic keys generated during KEX.

Real-World Application:

Secure Remote Access: Protects login credentials from MITM (Man-in-the-Middle) attacks.

Cloud & Datacenter Networks: Ensures secure SSH connections across remote infrastructure.

✅ Reference: Huawei HCIE-Datacom Guide – SSH Key Exchange and Authentication