Nortel Networks 8683POS User Manual

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Chapter 2 Using the Passport 8683POS Module
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Using the Passport 8683POS Module
  
Single-mode fiber (SMF) 
Multimode fiber (MMF).
Point-to-Point Protocol
The PPP family of protocols is divided into three categories:
Control protocols control operation and maintenance of the PPP link.
Network protocols describe the encapsulation methods needed to move 
multiprotocol network traffic over the PPP interface.
Network control protocols are used to configure, manage, and control the 
operation of the network protocols. The Passport 8683POS Module uses the 
Link Control Protocol (LCP) and the Link Quality Report to monitor the link.
PPP goes through the following basic initialization phases when bringing up links:
Link establishment
Network layer protocol
Establishing the PPP link
The Link Control Protocol (LCP) of the PPP helps establish a link. LCP generates 
three types of packets:
Link configuration packets, including configure-request, configure-ACK, 
configure-NAK, and configure-reject packets
Link termination packets, including terminate-request and terminate-ACK 
packets
Link maintenance packets, including code-reject, protocol-reject, 
echo-request, and echo-reply packets
When two devices initialize a PPP dialog, each sends a configure-request packet 
to the other. Each configure-request packet contains a list of LCP options and 
corresponding values that the sending device uses to define its end of the link.
Note: 
The estimated maximum transmission distance for OC-3c SMF is 
20 kilometers (km); for OC-3c MMF is 2 km; for OC-12c SMF is 15 km; 
for OC-12c MMF is 500 m.