1tswtclmt(7ipp) IP Quality of Service Modules tswtclmt(7ipp)
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6 tswtclmt - Time Sliding Window Three Conformance Level Meter
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9 The Time Sliding Window Three Conformance level meter (tswtcl) meters a
10 traffic stream and determines the conformance level of its packets.
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13 Packets are deemed to belong to one of the three levels, Red, Yellow or
14 Green, depending on the committed and peak rate.
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17 The meter provides an estimate of the running average bandwidth. It
18 takes into account burstiness and smoothes out its estimate to approx‐
19 imate the longer-term measured sending rate of the traffic stream.
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22 The estimated bandwidth approximates the running average bandwidth of
23 the traffic stream over a specific window (time interval). tswtcl esti‐
24 mates the average bandwidth using a time-based estimator. When a packet
25 arrives for a class, tswtcl re-computes the average rate by using the
26 rate in the last window (time interval) and the size of the arriving
27 packet. The window is then slid to start at the current time (the
28 packet arrival time). If the computed rate is less than the committed
29 configuration parameter, the packet is deemed Green; else if the rate
30 is less than the peak rate, it is Yellow; else Red. To avoid dropping
31 multiple packets within a TCP window, tswtcl probabilistically assigns
32 one of the three conformance level to the packet.
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35 The tswtcl module exports global and per-class statistics through
36 kstat:
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39 Global statistics:
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41 module: tswtclmt instance: <action id>
42 name: tswtclmt statistics class <action name>
43 green_bits <number of bit in green>
44 green_packets <number of packets in green>
45 red_bits <number of bits in red>
46 red_packets <number of packets in red>
47 yellow_bits <number of bits in yellow>
48 yellow_packets <number of packets in yellow>
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52 /kernel/ipp/sparcv9/tswtclmt
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54 64-bit module (SPARC only.)
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58 See attributes(5) for descriptions of the following attributes:
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63 ┌─────────────────────────────┬─────────────────────────────┐
64 │ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
65 ├─────────────────────────────┼─────────────────────────────┤
66 │Availability │SUNWqos │
67 └─────────────────────────────┴─────────────────────────────┘
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70 ipqosconf(1M), dlcosmk(7ipp), dscpmk(7ipp), flowacct(7ipp),
71 ipqos(7ipp), ipgpc(7ipp), tokenmt(7ipp)
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74 RFC 2859, A Time Sliding Window Three Colour Marker (TSWTCM) W. Fang,
75 N. Seddigh, B. Nandy — The Internet Society, 2000
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79SunOS 5.11 29 Sep 2004 tswtclmt(7ipp)