> # CHAP Authentication

> Challenge Handshake Authentication Protocol (CHAP) is a challenge-response authentication protocol that uses the industry-standard Message Digest 5 (MD5) hashing scheme to encrypt the response. CHAP is used by various vendors of network access servers and clients. A server running routing and remote access supports CHAP so that remote access clients that require CHAP are authenticated. CHAP is supported as an authentication method in this release.

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