Re: [PATCH v2] Re: WAN: new PPP code for generic HDLC

James Chapman
2008-04-21T19:31:24Z

Krzysztof Halasa wrote:
> David Miller <davem@davemloft.net> writes:
>
>> I'll fix it properly because I know you won't do the work.
>
> Great to read that.
>
> Just few friendly after all notes so that you don't waste your time
> learning that yourself:
> - my patch didn't give us a third PPP implementation, we already have
> three: generic PPP, syncppp and PPP for ISDN :-)
> - of those, both generic PPP and (I think) ISDN PPP are in a good
> shape
> - generic PPP is specialized for dial-up async devices and has the
> required features (in kernel and in userspace pppd) - auth,
> multi-line, compression etc. It's a "lets give /dev/ttyS* a network
> device" implementation.

Generic ppp isn't specialized at all, and it isn't limited to async
serial devices. PPPoE, PPPoATM and L2TP use it.

> - ISDN PPP does for ISDN cards basically the same as generic PPP does
> for terminals. They are completely different from syncppp as the
> needs are completely different. Fixed-line PPP must be small and
> fast, and self-contained.

<snip>

> That's why I came to an idea that leaving syncppp and the old drivers
> in their current bit-rotting state which nobody can really fix, and
> using another (fourth, and third when syncppp eventually dies) PPP
> implementation is the only way out of this situation.

Can you elaborate on why the code that uses syncppp can't use the
generic ppp code together with a userspace ppp control protocol
implementation like pppd?

--
James Chapman
Katalix Systems Ltd
http://www.katalix.com
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