Ppp O E Configuration; Introduction To Pppoe - 3Com MSR 50 Series Configuration Manual

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Introduction to PPPoE

PPP E C
O ONFIGURATION
When configuring PPPoE, go to these sections for information you are interested
in:
"Introduction to PPPoE" on page 393
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"Configuring PPPoE Server" on page 394
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"Configuring PPPoE Client" on page 395
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"Displaying and Maintaining PPPoE" on page 397
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"PPPoE Configuration Example" on page 397
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PPPoE
Point-to-point protocol over Ethernet (PPPoE) connects a network of hosts formed
by Ethernet to a remote access device to gain access to the Internet. It allows you
to perform access control and accounting on a per-host basis. As it is highly
cost-effective, PPPoE is widely adopted, for example, in network constructions for
residential areas.
PPPoE adopts the client/server model. It provides point-to-point connectivity over
Ethernet by encapsulating PPP packets in Ethernet frames.
PPPoE is divided into two distinct phases: discovery and PPP session.
Discovery phase
■
When a host wants to start a PPPoE process, it must first identify the MAC address
of the Ethernet on the access end and create the SESSION ID of PPPoE. This is the
very purpose of the discovery phase.
PPP session phase
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After entering the session phase of PPPoE, the system can encapsulate the PPP
packet as the payload of PPPoE frame into an Ethernet frame and then send the
Ethernet frame to the peer. In the frame, the SESSION ID must be the one
determined at the discovery phase, MAC address must be the address of the peer,
and the PPP packet section begins with the Protocol ID. In the Phase of Session,
either the host or the server may send PPPoE Active Discovery Terminate (PADT)
packets to notify the other to end this Session.
For more information about PPPoE, refer to RFC 2516.
PPPoE server
The device allows you to configure PPPoE server which provide the following
functions: