Shulou(Shulou.com)05/31 Report--

Audio commentary

Hello, everyone. The meeting will answer your questions. Pppoe through what protocol for data encapsulation, pppoe discovery phase includes interactive messages that many people do not know, now let's take a look at it!

Answer:

1. In the discovery phase, the user host searches all connected access concentrators or switches in a broadcast-like manner, obtains their Ethernet MAC addresses, then selects the access concentrator to be accessed, and determines the unique identification number of the PPP session to be established; there are four steps in the discovery phase. When this phase is completed, both sides of the communication know the PPPoE session identity and the Ethernet address of the peer, and define the PPPoE session uniquely together.

2. The four steps in the development phase are as follows:

3. Host broadcast initiation packet (PADI). The destination address of the packet is the broadcast address of Ethernet 0 ffffffff, and the value of the CODE field is 00SESSION-ID. The Padi packet must contain at least one label of the service name type (the label type field value is 00101), and propose the required services to the access concentrator.

4. The access concentrator receives PADI packets within the service range and sends PPPoE valid discovery and provisioning packets (PADO packets) in response to the request; the value of the code field is 00. The session identification field is still 00000. The Pado packet must contain an access concentrator name type tag (label type field value is 00102), and one or more service name type tags indicating the type of service that can be provided to the host.

5. Select the appropriate PADO packet from the multiple PADO packets that the host may receive, and then send the PPPoE valid Discovery request packet (padr) to the selected access concentrator; where the CODE field is the 01SESSION_ID field value is still 00000 placePADR packet must contain a service name type tag to determine the type of service requested from the access hub (or switch) When the host does not receive the PADO within a specified period of time, it should resend its PADI packet and double the wait time. This process will be repeated many times as expected.

6. After receiving the PADR packet, the access concentrator is ready to start the PPP session and send the PPPoE effective discovery session confirmation PADS packet; where the code field value is the 06SESSION-ID field value is the unique PPPoE session identification number generated by the access concentrator; the PADS packet must also contain the access concentrator name tag to confirm the service provided to the host; when the host receives the PADS packet confirmation, both parties enter the PPP session phase.

This is the end of this article. I hope it will be helpful to all of you.

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