How BRAS actually work in detail (Root level information)

B-RAS & Radius Server interaction can work in a number of ways. The example below is a typical example

1. User (CPE or User PC can do this) initiates PPP authentication to the B-RAS

2. B-RAS prompts for username and password (if Password Authentication Protocol [PAP]) or challenge (if Challenge Handshake Authentication Protocol [CHAP]).

3.User replies.

4. Once the user is authenmticated by the B-RAS it sends the username and encrypted password to the RADIUS server. (Access Request)

5. RADIUS checks this against its database and responds with Accept, Reject, or Challenge.

5a. If the user exists and the password is correct the the server sends "Access-Accept"

5b. If the user does not exist or password is incorrect then the server sends "Access-Reject"

5c The server can send "Access-Challenge" (random number) to the B-RAS The B-RAS must respond correctly for authentication to be complete. This is optional and dependant on the authentication model required.

6. The B-RAS acts upon services (i.e supplies require IP from a pool or relases static IP) and services parameters (i.e. QoS) as bundled with Accept or Reject.


I hope this helps.

R

Hi there,

Just wondering if someone could confirm some B-RAS synonyms for me: RAN (remote access node) and ERX (edge router ...?) - are these one and the same or are they different pieces of equipment serving different functions in a broadband network?

thanks!

Hi Unlight,

Welcome to firewall!

With regards to your question:

RAN - Remote Access Node (or if Mobile broadband Radio Access Network)

ERX - Not a synonym but a product name/ ERX was (is?) a B-RAS sold by siemens/juniper

Hope that helps

R

Hiya, thanks for the info and welcome (: I was trying to clarify a diagram I got of my countries DSL network.