>>>>> "jamal" == jamal <hadi@xxxxxxxxxx> writes:
jamal> On Tue, 8 Feb 2000, Michal Ostrowski wrote:
>> So if you want to do PPP/UDP:
>>
>>
>>
>> As the "type" suggests, you get PPP semantics.
>>
jamal> There is a catch with this: You now have to muck with the
jamal> UDP kernel code to add L2TP semantics; most other people
jamal> would probably only want to use UDP as it is.
If done by new parameters to the socket() call, I think the last (protocol)
parameter would be more appropriate. e.g.
socket(AF_INET,SOCK_DGRAM,IPPROTO_PPP_UDP);
That would allow for running ppp over any reasonable protocol in
the AF_INET family (just need to add a IPP_PROTO_* for every reasonnable
protocol).
On the other hand, I don't see what introducing new parameter values would
gain at all. An ioctl, which attaches the socket's data path to the ppp channel
would serve the same thing. It is even more flexible as it would allow
to delay connecting the ppp channel. After a succesful connect() or accept(),
the user space program could communicate some none-ppp related
data with the peer before it attaches the socket to the ppp channel.
This could be useful for different things, e.g.
- performing additional authentification
- negotiating some enryption for the channel
- if it is not known a-priori that the peer really wants to speak ppp,
some heuristic algorithm might be able to analyse the first data
received from the peer and switch to an alternative protocol when
detected so.
Henner
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