Airspan AS3010, Руководство по вводу в эксплуатацию

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D ef in ing PP P oE C o m m i ssi o n i n g M an u al
17.1. Overview
It is desirable to connect multiple hosts at a remote site through the same customer
premise access device. It is also a goal to provide access control and billing
functionality in a manner similar to dial-up services using Point-to-Point Protocol
(PPP). In many access technologies, the most cost-effective method to attach
multiple hosts to the customer premise access device is through Ethernet. In
addition, it is desirable to keep the cost of this device as low as possible while
requiring little or no configuration.
PPPoE provides the ability to connect a network of hosts over a simple bridging
access device to a remote Access Concentrator. With this model, each host utilizes
it’s own PPP stack and the user is presented with a familiar user interface. Access
control, billing and type of service can be done on a per-user, rather than a per-site
basis.
PPPoE has two distinct stages: a "discovery stage" and a "PPP session stage". When
a host wishes to initiate a PPPoE session, it must first perform discovery to identify
the Ethernet MAC address of the peer and establish a PPPoE session ID. While PPP
session stage defines a peer-to-peer relationship, discovery is inherently a client-
server relationship. In the discovery process, a host (the client) discovers an access
concentrator that the host can communicate with. The discovery stage allows the
host to discover all access concentrators and then select one. When discovery
completes successfully, both the host and the selected access concentrator have the
information they will use to build their point-to-point connection over Ethernet.
The discovery stage remains stateless until a PPP session is established. Once a PPP
session is established, both the host and the access concentrator MUST allocate the
resources for a PPP virtual interface.
The PPPoE method in ASWipLL is described below:
1.
2.
3.
4.
The Data Terminal Equipment (DTE) client requests PPPoE service with a
broadcast message to the SPR.
The SPR then sends the request to the BSR.
The BSR contains a MAC address table of all LAN side DTEs.
If valid, the BSR sets up a transparent PPPoE bridge to the server.
17-2 Airspan Networks Inc. 01040311-07