<br>QUESTION NO: 69<br>Which of the following options can be negotiated using LCP during the PPP link establishment? (Choose<br>three)<br>A. callback<br>B. IPCP<br>C. CHAP<br>D. multilink<br>E. TCP<br>F. Q.931<br>Answer: B C D(怎么A不能选,IPCP不是NCP的内容)<br>Explanation:<br>? The NCP phase is used for establishing and configuring different network-layer protocols.<br>? The most common layer 3 protocol negotiated is IP. The routers exchange IP Control Protocol (IPCP)<br>messages negotiating options specific to the protocol.<br>? Point-to-Point Protocol (PPP) currently supports two authentication protocols: Password Authentication<br>Protocol (PAP) and Challenge Handshake Authentication Protocol (CHAP). Both are specified in RFC<br>1334 and are supported on synchronous and asynchronous interfaces.