> 1) Can somebody tell me the exact difference between a > class and a qdisc? Martin Brown did try to explain to > me but, I couldn't understand! The qdisc is what actually does the job. Some qdiscs allw you to define classes in them, but the kernel doesn't care about that. The kernel delivers a packet to the qdisc and it up to it to decide what to do with it (classify the packet etc..) > 3) 'HTB is suited for fixed bandwidth' ... by "fixed" > what exactly is meant ... meaning can it be used where > bandwidth is shared but at almost always a certain > "fixed" bandwidth is available (even if available > bandwidth exceeds, it will be by only a few bytes, for > a short duration)? Since HTB takes bandwidth as parameters, to really have any effect you'll have to know how much bandwidth preciselly you have. Like if you have 128kbps ISDN, you must set HTB classes so that cumulative rates of the classes are not bigger that your real limit. If not the shapping will not be correct and precise. > 5) The lartc howto speaks about 'mpu' with reference > to TBF, and states "for ethernet, no packet uses less > than 64 bytes", can you please tell me whether 64 > bytes is the least possible; meaning adding 20 bytes > of IP and 28 bytes of TCP, I believed a TCP/IP packet > with no payload could exist of 48 bytes, is this > possible? and if a payload must be added, should it be > 16 bytes atleast, can I not have a 52 byte ethernet > packet? Kindly explain. Ethernet is not the same as TCP/IP! And TC can shape other protocols than IP. An ethernet packet (actually a frame) is: 8 bytes preamble 6 bytes src MAC address 6 bytes dst MAC address 2 bytes type DATA (46â1500) bytes 4 bytes Checksum = 72-1526 bytes, now the OS actually doesn't see the preamble so the minimal ethernet frame in the OS is 64bytes. -- Damjan Georgievski jabberID: damjan@xxxxxxxxxxxx _______________________________________________ LARTC mailing list / LARTC@xxxxxxxxxxxxxxx http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/
