Panasonic UF-E1, Service Manual

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UF-E1
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5. PPP Link Processing (RFC 1661)
Figure 6.5.2.6 shows the outline of the transition of PPP states and Table 6.5.2.4 shows the details of
transition. After the system is booted, link is established by LCP. When this is done, the negotiation
(adjustment) for link setting option is conducted at the same time. This is not done on everything but
only for those that do not depend on network protocol. The options that are related to network protocol
are conducted by each NCP. After the link establishment phase comes authentication phase. If authen-
tication fails, then the phase will transfer to link termination phase.
The authentication phase can be omitted. After this phase, each NCP conducts setting for network pro-
tocols to be used. This makes it possible for IP and other network protocols to function. Below are
descriptions for different phases in Figure 6.5.2.6.
Figure 6.5.2.6 Transition chart of PPP (outline)
Key Point
5 phases
1
Link Dead phase
Physical-electrical stop
Option/default change
authorization use request
Link setting
request packet
Only LCP can be sued
Non-LCD packet ignore
LCP authorization protocol'
Quality monitoring packet usable
CP/NCP/Network Layer
protocols usable
Link closed/ CD-OFF/ Authorization failed/
Link quality failed/ Idle time out
Link Open Sate
NCP open state
Physical-electrical boot (CD-ON, etc.)
Link setting request packet
Send/Receive setting
authorization packet
Authorization
Authorization
failed
NCP Open/Close
End request packet
Notice to network layer
(End request transmission side) End acknowledge receive
or elapse of restart timer
(End request receive side) End acknowledge transmission
2
IP becomes open in the network layer protocol phase
1
Link Establishment phase
2
Authorization phase
3
Network layer Protocol phase
4
Link Termination phase
The signal of physical layer cutting
5