Yes, I do understand the LARTC and wondershaper. As for ADSL-qos I didn't, but I did read all the TCP rfcs regarding packet lose and throughput negotiation, ect. --- Ed Wildgoose <lists@xxxxxxxxxxxxxx> wrote: > > >Yes, SwFC is lame. Howerver it would be a good band-aid, to have > router > >and modem syncronisation take place. > > > > > > You have got to consider that some devices are asynchronous and some are > > synchronous > I don't follow you? The router would never tell the modem to stop the downward, exept for the rare cases where you need HW_FLOWCONTROL. As for upward that has the most problems where moving to a slower bandwith. > >The router(PC) has no idea of the buffer fullness, this is the > underlying > >problem! The cable modem needs to triger a "pause" when it's buffer > >reaches %80 full, regardless of any other rate limiting. Linux kernel > can > >do this with some cards, under heavy CPU strain(htb). > > > >CONFIG_NET_HW_FLOWCONTROL: net/Kconfig > > > > > > Possibly, but this doesn't help you that much. If your http download is > > whacking out packets then your SSH session will still effectively get > crowded out. > > You want something to queue for a bit and prioritise this extra traffic. > > ....you have read the LARTC Howto haven't you? > This is where tos comes into play. Most users won't need much more then pfifo_fast with a 3 second fifo buffer in the modem. Keep in mind we only use the modem's fifo buffer for overflow(%20 to %80). > >>You need something which works at IP level or above. TCP (level > higher) > >> > >> > >No, the DEVICE is not > layer 3. It's simply a bridge, with a > stoplight > >on one end. The idea is to not make any cars crash, that has nothing > todo > >with the ball game a car might want to get too. > > > > > ?? The DEVICE is a modem, like a serial v.34, ect. It's a bit of hardware and some modulation protocol. So there's no need for it to work with the upper layers. It's sufficent for the device to use it's ?ethernet/USB? line to signal a pause when it's gettting congested. This means that any router attached to it is responsible for carrying out the upper layers flow control(ECN). > > > >Yes, ECN will/should be used for routers attached to bridges. > > > > > > Not as far as I am aware? (today) This was my next question, dose htb or tbf effect linuxes ECN? Directly or indirectly? > > > >>broadly unsupported. ICMP stuff is frequently dropped by > >>routers/firewalls making it problematic (look at how difficult it is > >>just to do MTU discovery!) > >> > >> > >> > >ECN makes this a non-issue. > > > > > > ??? Eh? ECN like IPv6 fixes some of the short commings in current technology. For non-ECN connections droping one packet will signal a leveling of bandwith(TC-SFQ). If a TCP conection loses 3 packets, regardless of what router droped each, it's bandwith is cut in half. It would be nice to add a droped packet monitor to linux's connection tracking and feed this into sfq. > > >>What's your question though? Read the LARTC howto and the ADSL QOS > >>howto. They are both excellent docs. Also read up on some basic TCP > >>notes. There is nothing really clever that you can do - it's all in > the > >> > >>docs you just have to work around the limitations of the protocols > >> > >> > >> > >I would like to know is maby a ?$6000.00? Cisco cable mobem will not > only > >use HwFC but ECN as well? Thought i'd like to find a $150.00 modem > that > >will just do HwFC, maby an internal one? > > > > > > No it won't. Well, even if it did, I don't think it would help. Unless > > the rest of the world understands your protocol then you will still have > > problems with incoming connections. > It's only a hardware flow control for a directly connected modem? There is no software protocol, exept ECN and TCP. That's what I'm saying is that the rest of the world FAILED to read about the ethernet standered and implement it correctly. Even thought it's clearly documented in the linux kernel how to implement. > You can get a £250 cisco adsl modem which looks rather powerful. Try > that if you want to experiment. > I have looked at cisco cable modems. I would hope that thay would not only have proper flow control, including ECN, but also have a big buffer with lots of TC. However they are out of my price range. > Please, please read the LARTC-Howto and ADSL-qos howto. I think it has > everything that you need. > > > > > > >>Ed W > >> > >> > >> __________________________________ Do you Yahoo!? Yahoo! Mail Address AutoComplete - You start. We finish. http://promotions.yahoo.com/new_mail _______________________________________________ LARTC mailing list / LARTC@xxxxxxxxxxxxxxx http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/
