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RFC1661 - часть 16

Since this is not the meaning of the Open event, it is

suggested that when an Open user command is executed in the

Opened, Closing, Stopping, or Stopped states, the

implementation issue a Down event, immediately followed by an

Up event. Care must be taken that an intervening Down event

cannot occur from another source.

The Down followed by an Up will cause an orderly renegotiation

of the link, by progressing through the Starting to the

Request-Sent state. This will cause the renegotiation of the

link, without any harmful side effects.


This event indicates that the link is not available for traffic;

Simpson [Page 17]

RFC 1661 Point-to-Point Protocol July 1994

that is, the network administrator (human or program) has

indicated that the link is not allowed to be Opened. When this

event occurs, and the link is not in the Closed state, the

automaton attempts to terminate the connection. Futher attempts

to re-configure the link are denied until a new Open event occurs.

Implementation Note:

When authentication fails, the link SHOULD be terminated, to

prevent attack by repetition and denial of service to other

users. Since the link is administratively available (by

definition), this can be accomplished by simulating a Close

event to the LCP, immediately followed by an Open event. Care

must be taken that an intervening Close event cannot occur from

another source.

The Close followed by an Open will cause an orderly termination

of the link, by progressing through the Closing to the Stopping

state, and the This-Layer-Finished action can disconnect the

link. The automaton waits in the Stopped or Starting states

for the next connection attempt.

Timeout (TO+,TO-)

This event indicates the expiration of the Restart timer. The

Restart timer is used to time responses to Configure-Request and

Terminate-Request packets.

The TO+ event indicates that the Restart counter continues to be

greater than zero, which triggers the corresponding Configure-

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