Configuring the PPPoE Client on CnPilot E-series devices

PPPoE is now a supported on CnPilot E-series devices.

Note: This feature is available from 3.1.1 r15 release build.

PPPoE Client Overview

PPPoE combines two widely accepted standards, Ethernet and PPP, to provide an authenticated method of assigning IP addresses to client systems. PPPoE clients are typically personal computers connected to an ISP over a remote broadband connection, such as DSL or cable service. ISPs deploy PPPoE because it supports high-speed broadband access using their existing remote access infrastructure and because it is easier for customers to use.

PPPoE provides a standard method of employing the authentication methods of the Point-to-Point Protocol (PPP) over an Ethernet network. When used by ISPs, PPPoE allows authenticated assignment of IP addresses. In this type of implementation, the PPPoE client and server are interconnected by Layer 2 bridging protocols running over a DSL or other broadband connection.

PPPoE is composed of two main phases:

  • Active Discovery Phase—In this phase, the PPPoE client locates a PPPoE server. During this phase, a Session ID is assigned and the PPPoE layer is established.
  • PPP Session Phase—In this phase, PPP options are negotiated and authentication is performed. Once the link setup is completed, PPPoE functions as a Layer 2 encapsulation method, allowing data to be transferred over the PPP link within PPPoE headers.

At system initialization, the PPPoE client establishes a session with the PPPoE server by exchanging a series of packets. Once the session is established, a PPP link is set up, which includes authentication using Password Authentication protocol (PAP). Once the PPP session is established, each packet is encapsulated in the PPPoE and PPP headers.

This mainly involves the following steps:

  1. Initiation - The client software sends a PPPoE Active Discovery Initiation (PADI) packet to the server to initiate the session.
  2. Offer - The server responds with a PPPoE Active Discovery Offer (PADO) packet.
  3. Request - Upon receipt of the PADO packet, the client responds by sending a PPPoE Active Discovery Request (PADR) packet to the server.
  4. Confirmation - Upon receipt of the PADR packet, the server responds by generating a unique ID for the PPP session and sends it in a PPPoE Active Discovery Session (PADS) confirmation packet to the client.

Configurating the PPPoE Client

1. Enable - To enable PPPoE client connection with PPPoE server.

2. VLAN - Interface on which client will run.

3. Auth - Username and Password to get authententication from PPPoE server.

4. MTU - Maximum Transmission Unit

5. TCP MSS-clamping - Enable or Disable MSS clamping.



Disable PPPoE client connection


Delete PPPoE client configuration



1. We can check the status of PPPoE client from Monitor page. We can also see whether it got IP address from PPPoE server.

PPPoE Running Status

2. PPPoE interface statictics, which shows the counters for packets received and sent by the PPPoE sessions

3. Default route details.