dummynet
- traffic shaper, bandwidth manager and delay emulator
DESCRIPTION
The
system facility permits the control of traffic
going through the various network interfaces, by applying bandwidth
and queue size limitations, implementing different scheduling and queue
management policies, and emulating delays and losses.
The user interface for
is implemented by the
ipfw(8)
utility, so please refer to the
ipfw(8)
manpage for a complete description of the
capabilities and how to use it.
Kernel Options
The following options in the kernel configuration file are related to
operation:
Additionally, one may want to increase the number
of mbuf clusters (used to store network packets) according to the
sum of the bandwidth-delay products and queue sizes of all configured
pipes.
The
facility
was initially implemented as a testing tool for
TCP
congestion control by
An Luigi Rizzo Aq luigi@iet.unipi.it ,
as described on ACM Computer Communication Review, Jan.97 issue.
Later it has been modified to work at the
IP
and bridging levels, integrated with the
ipfw(4)
packet filter, and extended to
support multiple queueing and scheduling policies.
