Am Donnerstag, 16. November 2006 17:37 schrieb Larry Brigman: > On 11/15/06, Daniel Musketa <Daniel@xxxxxxxxxx> wrote: > > I can watch traffic coming in on ppp0 with `iftop` and it never exeeds > > 900kbit. Why could a 2000kbit headroom be not enough for clean receiving > > of 80kbit VoIP data? > > Because [...] what comes first, goes out first. Also if the download > side can send at a higher rate than you line can handle, there > will be a queue of packets at the router handling the bandwidth > limititation. `iftop` shows me a rate of 800kbit for packets going out to the LAN on eth1. This is the ceil value for egress shaping from router to LAN. But I also can watch the download rate of packets coming in from ppp0. And it's never more than 900kbit, so TCP's mechanism of lowering TX speed after delayed/missing ACKs seems to work. To me it looks as if there wasn't a filled queue on the ISP's side of the line. `tc -s ...` shows me a backlog of about 20p in the "download class". I still can't understand why more than 2 Mbit free bandwith and an empty queue can cause drop outs ... mmh ... Daniel _______________________________________________ LARTC mailing list LARTC@xxxxxxxxxxxxxxx http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc
