On Wed, 02 Aug 2006 19:21:27 +0200 Rainer Baumann <[EMAIL PROTECTED]> wrote:
> Hi, > > We developed an extension to the network emulator netem, that provides > emulation of long term network properties such as long-range dependence > and self-similarity of cross-traffic. It is not possible to emulate > these properties with the statistical tables for the packet delay > values used by the original netem. > > We read the values for the packet delay, drop, loss and corruption from > a pre-generated trace file. This trace file is obtained by monitoring > network traffic and writing all actions to a trace file. During the > emulation the packets get processed according the values in such a trace > file. Detailed information are available on our > Webseitehttp://tcn.hypert.net > > A new option (trace) has been added to the netem command. If the trace > option is used, the values for packet delay etc. are read from a trace > file, afterwards the packets are processed by the normal netem functions. > The packet action values are readout from the trace file in user space > and sent to kernel space via procfs. > > The evaluation results show similar behavior for our enhancement and the > original netem with respect to packet delay precision and packet loss at > high load (e.g. 80'000 packets per second). > It is possible to add, change or delete multiple netem qdiscs on-the-fly > (original netem qdiscs and trace qdiscs mixed). > > We are looking forward for any comments, feedback and suggestions! > > Thanks, > Rainer I like the idea and want to get it incorporated. Major things that need fixing: * Don't extend size of tc_netem_qopt instead use a new netlink payload. + add type to TCA_NETEM_ enum + new structure containing the payload This allows for binary compatiablity. * Don't use proc for a interface to netem features. Use netlink. Either add a new command (or option) to the iproute2 commands to handle flow table, or add a new payload. Minor stuff: * the bzero macro in netem is a BSDism, just use memset * bad indentation and style issues. * minor whitespace damage in several places in patch - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
