Pppoe Configuration; Introduction To Pppoe - H3C SR6600 Configuration Manual

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PPPoE Configuration

This chapter includes these sections:

Introduction to PPPoE

Configuring a PPPoE Server
Displaying and Maintaining PPPoE
PPPoE Configuration Example
Introduction to PPPoE
PPPoE
Point-to-Point Protocol over Ethernet (PPPoE) can provide access to the Internet for the hosts in an
Ethernet through a remote access device and implement access control and accounting on a per-host
basis. Integrating the economy of Ethernet and scalability and management functions of PPP, PPPoE
has gained popularity in various application environments, such as residential networks.
PPPoE adopts the client/server model. It can establish point-to-point links in Ethernet. With PPPoE
employed, PPP packets are encapsulated in Ethernet frames.
PPPoE undergoes two phases: discovery and PPP session, as described below.
Discovery phase, where a PPPoE session is initiated. In this phase, the host obtains the MAC
address of the access end and generates the PPPoE session ID. When the discovery phase ends,
the PPPoE session ID between the host and the server is determined, and the PPP session phase
begins.
PPP session phase, where PPP packets are encapsulated in Ethernet frames before being sent to
the peer. In the frame, the session ID must be the one determined in the discovery phase, the MAC
address must be that of the peer, and the PPP packet section begins from the Protocol ID field. In
the session phase, either side of the link can terminate the session by sending PPPoE Active
Discovery Terminate (PADT) packets.
For more information about PPPoE, see RFC 2516.
PPPoE server
The router can operate as a PPPoE server to provide the following functions:
Dynamic IP address allocation.
Multiple authentication methods, such as local authentication and RADIUS/TACACS+. When
accompanied by the packet-filtering firewall or state firewall, a PPPoE server can provide security
for networks connecting the Internet through Ethernet, such as campus networks and residential
networks. This, however, requires installation of PPPoE client dial-up software on hosts.
PPPoE client
PPPoE is widely used in ADSL broadband access applications. Normally, to enable a host to access the
Internet through ADSL, PPPoE client dial-up software is required on the host. You can run PPPoE client
dial-up software on the router. In this case, the router operates as a PPPoE client and can thus provide
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