Re: PPP state machine

[James Carlson <carlsonj@carlson.workingcode.com>]

Bhaskar-ROCSYS writes:
 > Hi
 > First of all thanks for the response.
 > 
 > To answer to big question of "Why?", farsync card that I am using has 4
 > interfaces.  And the application in which i am working on may need all
 > the 4 interfaces to be up.
 > If I have to use the existing code, then I need to run 4 different
 > instances of pppd.

Right.  Is having four daemons a problem?  It makes the links easy to
administer and configure.  What's the problem being solved?

 >  And if I want to use the same code, then I need to
 > go for a design similar to pppoe.  For such design i need to write code
 > both in kernel space and user space.

Since you're talking about sync PPP, I don't understand the reference
to PPPoE.  PPPoE is a bit of an ugly hack that involves (on Linux)
multiple trips in and out of the kernel for the data path.  I don't
know why you'd want to do that.

The user space daemon already supports running on sync ports, and the
implementation is efficient -- it doesn't involve the pty tricks as
done for PPPoE.  The data path is all in the kernel.

As far as I can tell, you don't need to change anything in user space.
You just need a sync driver for your card.

 > I decide to stick to kernel space and implement the complete state
 > machine in kernel space.  I am only interested in state machine.  Once
 > this is done I will initiate the state machine from the sync ppp code.
 > 
 > I think for implementing the state machine is independent of the mode.

In that case, best of luck.