[openbeosnetteam] Re: PPP up/opened

> > My problem was that PPP can be in the started phase while the interface
> > is still down. This has no use. Why doesn't an up request start the
> > interface so that they can be combined into the same request?
>
> I'm not sure.
> Maybe for AutoDial support, the PPP protocol is started, but will
> up the interface behind him only on first packet sent thru him.
> Or because behind PPP protocol, it's not always directly a interface, it
can be
> a sub-protocol, like PPPoE or PPPoA, which both encapsulate PPP frames
before
> give them to ethernet or ATM interface, respectivly.

I think when you open the interface it is ready for an UP event that can be
caused by an incoming connection. This is only useful if you wait for an
incoming connection, i.e. you set up a PPP server.

The autodial support could be implemented with this, too. How does pppd in
BSD do that? How do we want to implement autodial?

Oh, I just found out that FreeBSD's user-land PPP implementation opens the
interface in "-auto" mode (autodial) and then waits for outgoing packets to
bring the interface up. So, you were right.

But how is a PPP server set up? Does an incoming connection result in UP and
Open events?

> > Why did they split that system into down&initial and down&started?
>
> Can I ask who are "they" here?

The inventors of PPP.

> > Maybe I will find out when I read everything two or three times?
>
> Reading TCP/IP Illustrated, I guess?

No, the PPP RFC. It is very hard to read. The text begins with the use of
terms like Restart Timer and Restart Counter, but explains them somewhere in
the end. This does not help you in the process of understanding PPP.
Many details in this RFC are not really clearly stated.
I had to read the RFC many times to understand that both ends send a
Conf-Req packet, not only the connector. Or is this wrong? :))

Waldemar

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