User's Manual

UTT Technologies Chapter 9 PPPoE Server
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Chapter 9 PPPoE Server
9.1 Introduction to PPPoE
The PPPoE stands for Point-to-Point Protocol over Ethernet, which uses client/server
model. The PPPoE provides the ability to connect the Ethernet hosts to a remote Access
Concentrator (AC) over a simple bridging access device. And it provides extensive access
control management and accounting benefits to ISPs and network administrators.
The PPPoE is a network protocol for encapsulating PPP frames in Ethernet frames to
provide point-to-point connection over an Ethernet network.
9.1.1 PPPoE Stages
As specified in RFC 2516, the PPPoE has two distinct stages: a discovery stage and a
PPP session stage. The following describes them respectively.
9.1.2 PPPoE Discovery Stage
In the PPPoE discovery stage, a PPPoE client will find a proper server, and then build the
connection. When a client initiates a PPPoE session, it should perform discovery to
indentify the PPPoE server¶s Ethernet MAC address, and establish a PPPoE session ID.
PPPoE Client
PPPoE Server
PADI
PADO
PADR
PADS
Figure 9-1 PPPoE Discovery Stage Flows
See Figure 9-1, the discovery stage includes the following four steps: