Руководство Пользователя для Netopia 2e-w

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Cayman 2E-W User’s Guide
How Your Cayman 2E-W Works
November 2000
C-7
Once a network connection is made, each peer negotiates its side of 
the link's configuration by sending a Configure-Request message that 
lists its complete set of proposed configuration settings. When one 
peer sends a Configure-Request, the other peer responds in one of 
three ways:
Configure-Ack – If every configuration option in the 
Configure-Request packet is both recognizable and acceptable, 
the second peer returns a Configure-Ack message that lists the 
complete set of proposed settings and indicates that the peer 
accepts the settings. All configuration options are acknowledged 
simultaneously.
Configure-Nak – If every configuration option in the 
Configure-Request is recognizable but some values are not 
acceptable, then the second peer returns a Configure-Nak 
message that identifies the unacceptable option settings and 
proposes new settings acceptable to the second peer. A 
Configure-Nak message may also include proposed 
configuration settings for options that the second peer requires 
but that the first peer did not include in its Configure-Request.
Configure-Reject – If one or more of the configuration options in 
a Configure-Request are not recognizable or are not acceptable 
for negotiation, the second peer returns a Configure-Reject 
message that identifies the rejected options. The first peer can 
then send another Configure-Request that does not include any 
of the options listed in the Configure-Reject.
 The negotiation mechanism is conducted independently in each 
direction: a setting negotiated for one peer does not apply to the 
other peer until it negotiates that option for itself. For example, if 
Peer A negotiates that it has a maximum receive unit of 1492 bytes 
with Peer B but Peer B does not negotiate its own MRU (implying 
that it uses the default value of 1500), then Peer A can send frames 
up to 1500 bytes long to Peer B but Peer B can send frames up to 
1492 bytes long to Peer A.