Technical Reference for ZyXEL omni.net series
7-1
Chapter 7
Point-to-Point Protocol (PPP)
Introduction to PPP
Point-To-Point Protocol (PPP) is designed for simple links, which transport packets between two
peers. These links provide full-duplex simultaneous bi-directional operation, and are assumed to
deliver packets in order. PPP is intended to provide a common solution for easy connection for a
wide variety of hosts, bridges and routers.
In the process of configuring, maintaining and terminating the point-to-point link, PPP goes
through several distinct phases, as specified in the following simplified state diagram:
Figure 7. Point-to-Point Link Pathway
Up
Opened
S
u
cce
ss/
N
o
n
e
Fail
Closing
Down
Fail
Idle
Establish
Network
Terminate
Authentication
Point-to-Point Link Pathway
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