ppp状态转移（PPP state transition）.docVIP

ppp状态转移（PPP state transition） Yesterday chat, we should structure on the PPP frame has a basic understanding, which in the frame structure, we will see a protocol field, respectively C02100218021 three code, in fact, this different code represents the current frame in the PPP state, we have the following 5 states PPP chat chat the. First, please look at the PPP status transition diagram in the attachment First, the two sides are in the link is not available, then there will be a proposed link request, if you want to establish point-to-point communication through PPP protocol, no matter which side of the equipment are required to send LCP data packets to configure the link, once the LCP configuration parameter option negotiations after the two sides would pass the letter according to the LCP configuration request authentication configuration parameter option in the negotiation message to determine link equipment using authentication method. The two sides is not the default protocol for authentication, and direct access to the NCP configuration option agreement, several configuration process experienced until completion, both to point to begin transmitting data packets through the network layer has an established link, the link will be available. Only when any end receives LCP or NCP link close message (in general agreement is not required on the road capacity of NCP closed, so normally closed data link message is issued in LCP negotiation phase or application session stage); the physical layer can not be detected by the carrier or the management of the link the closing operation, the link will disconnect, thereby terminating the PPP session. The following is a status transition diagram of the PPP protocol that needs to be experienced throughout the link process: PPP needs to go through the following phases during the configuration, maintenance, and termination of the point to point link: Link unavailability phase. Sometimes referred to as the physical layer unavailab