Patrick McHardy wrote: > This is currently all there is. If you have some specific questions, > just ask (but please CC lartc). If anyone wants to write some > documentation I'd be happy to help, but I don't have time for it > myself. I am not sure if the original poster has specific questions, but I sure do. I just recently got into this HFSC mess myself, so I'm a bit fuzzy in all the terms and differences in implementation. I read the paper (SIGCOM97) on HFSC and I think I understood most of it. But there are some things in the implementation that I couldn't really realize. I'll quote the usage here for reference: ,---- | Usage: ... hfsc [ rt SC ] [ ls SC ] [ ul SC ] | | SC := [ [ m1 BPS ] [ d SEC ] m2 BPS | | m1 : slope of first segment | d : x-coordinate of intersection | m2 : slope of second segment `---- Okay, the SC parameters I think I understand rather well - they are there to define the service curve itself. But the way hfsc takes three optional parameters of service curves puzzles me. I believe 'rt' referes to 'Real-Time Service Curve', 'ls' to 'Link Sharing Service Curve' and 'ul' to 'Upper Limit Service Curve'. If I understand correctly, the SIGCOM97 paper mentioned that the link sharing selection need not be the same as the real time selection, but in examples assumed for simplicity that they were. Also, from the source I conclude that 'Upper Limit Service Curve' cannot be specified without 'Link Sharing Service Curve'. So, this, all in all, baffles me :-) The possible combinations I can make here are: Real-Time Link-Sharing Real-Time, Link-Sharing Link-Sharing, Upper-Limit Real-Time, Link-Sharing, Upper-Limit How do these behave? If I specify *only* the real-time curve, what is used for the link-sharing part? Or does that mean that there is no sharing? Or if I only specify the link-sharing curve, does that mean that no specific deadlines are for packets, just that they are sent based on the link-sharing model? And what actually is the upper-limit service curve? I take it that it is some kind of a packet drop curve, but I don't know how it would behave - nor why it would require the link-sharing curve. So, any pointers on these would be helpful, or if you manage to get the time to explain it specifically. I will probably cook up atleast an example script using HFSC for normal QoS if I manage to understand how it works, perhaps even some documentation. -- Naked _______________________________________________ LARTC mailing list / LARTC@xxxxxxxxxxxxxxx http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/
