TSWTCLMT(7IPP)TSWTCLMT(7IPP)NAMEtswtclmt - Time Sliding Window Three Conformance Level Meter
DESCRIPTION
The Time Sliding Window Three Conformance level meter (tswtcl) meters a
traffic stream and determines the conformance level of its packets.
Packets are deemed to belong to one of the three levels, Red, Yellow or
Green, depending on the committed and peak rate.
The meter provides an estimate of the running average bandwidth. It
takes into account burstiness and smoothes out its estimate to approx‐
imate the longer-term measured sending rate of the traffic stream.
The estimated bandwidth approximates the running average bandwidth of
the traffic stream over a specific window (time interval). tswtcl esti‐
mates the average bandwidth using a time-based estimator. When a packet
arrives for a class, tswtcl re-computes the average rate by using the
rate in the last window (time interval) and the size of the arriving
packet. The window is then slid to start at the current time (the
packet arrival time). If the computed rate is less than the committed
configuration parameter, the packet is deemed Green; else if the rate
is less than the peak rate, it is Yellow; else Red. To avoid dropping
multiple packets within a TCP window, tswtcl probabilistically assigns
one of the three conformance level to the packet.
STATISTICS
The tswtcl module exports global and per-class statistics through
kstat:
Global statistics:
module: tswtclmt instance: <action id>
name: tswtclmt statistics class <action name>
green_bits <number of bit in green>
green_packets <number of packets in green>
red_bits <number of bits in red>
red_packets <number of packets in red>
yellow_bits <number of bits in yellow>
yellow_packets <number of packets in yellow>
FILES
/kernel/ipp/sparcv9/tswtclmt
64-bit module (SPARC only.)
SEE ALSOipqosconf(1M), dlcosmk(7ipp), dscpmk(7ipp), flowacct(7ipp),
ipqos(7ipp), ipgpc(7ipp), tokenmt(7ipp)
RFC 2859, A Time Sliding Window Three Colour Marker (TSWTCM) W. Fang,
N. Seddigh, B. Nandy — The Internet Society, 2000
Sep 29, 2004 TSWTCLMT(7IPP)
