advancing metrics on the standards track
DESCRIPTION
Advancing Metrics on the Standards Track. Lab Testing Results draft-morton-ippm-advance-metrics-01 Al Morton July 2010 ACK: Len Ciavattone for NetProbe. Outline. Definition-centric metric advancement Possible Report Template Supports the Protocol Action Request - PowerPoint PPT PresentationTRANSCRIPT
1
Advancing Metrics on the Standards
TrackLab Testing Results
draft-morton-ippm-advance-metrics-01
Al Morton July 2010ACK: Len Ciavattone for NetProbe
2
Outline Definition-centric metric advancement Possible Report Template
Supports the Protocol Action Request Examples of the Definition-centric
approach: Revised Lab test methods Results for one implementation
Open call for participation in Lab tests
3
Definition-Centric Process (revised) ,---. / \ ( Start ) \ / Implementations `-+-' +-------+ | /| 1 `. +---+----+ / +-------+ `.-----------+ ,-------. | RFC | / |Check for | ,' was RFC `. YES | | / |Equivalence..... clause x -------+ | |/ +-------+ |under | `. clear? ,' | | Metric \.....| 2 ....relevant | `---+---' +----+---+ | Metric |\ +-------+ |identical | No | |Report | | Metric | \ |network | +--+----+ |results+| | ... | \ |conditions | |Modify | |Advance | | | \ +-------+ | | |Spec +----+RFC | +--------+ \| n |.'+-----------+ +-------+ |request | +-------+ +--------+
4
Key Points (the sub-points) Start with an RFC
Focus on a specific clause Run test(s) with Implementations
Test plan is customized to a specific clause Evaluate Measurements & Compare
Expected measurement results are Clear Obvious place to take action if text is found to be
ambiguous Final state is Report Dev. for Protocol Action Req.
5
Test Set-up (more details in I-D)
Network Emulator
NetProbe MS-1
NetProbe MS-2
NetProbe MS-3
NetProbe MS-4
eth2 10.201.0.254
eth3 10.202.0.254
eth4 10.203.0.254
eth5 10.204.0.254
negotiated 100baseTx-FD
10.201.0.1
10.202.0.1
10.203.0.1
10.204.0.1
ManagementLAN
Test LANs
6
NetProbe 5.8.5 Runs on Solaris (and Linux, occasionally) Pre-dates *WAMP, functionally similar Software-based packet generator Provides performance measurements
including Loss, Delay, PDV, Reordering, Duplication, burst loss, etc. in post-processing on stored packet records
7
Report Template – Loss Threshold 3.1. One-way Delay, Loss threshold, RFC
2679 (procedure) 3.1.1. NetProbe Lab results for Loss Threshold 3.1.2. XXX Lab Results for Loss Threshold
<your compliant implementation here> 3.1.3. Conclusions on Lab Results for Loss
Threshold
8
Section 3.1 – Loss Threshold See Section 3.5 of [RFC2679], 3rd bullet point and also
Section 3.8.2 of [RFC2679]. 1. configure a path with 1 sec one-way constant delay 2. measure (average) one-way delay with 2 or more
implementations, using identical waiting time thresholds for loss set at 2 seconds
3. configure the path with 3 sec one-way delay (or change the delay while test is in progress, measurements in step 2)
4. repeat measurements 5. observe that the increase measured in step 4 caused all
packets to be declared lost, and that all packets that arrive successfully in step 2 are assigned a valid one-way delay.
Results: 22 of 38 packets were declared lost (post-process).
9
Section 3.2: First-bit to Last-bitSee Section 3.7.2 of [RFC2679], and Section 10.2 of [RFC2330].
1. configure a path with 1000 ms one-way constant delay, and ideally including a low-speed link (10-baseT, FD)
2. measure (average) one-way delay with 2 or more implementations, using identical options and equal size small packets (e.g., 32 octet IP payload)
3. maintain the same path with 1000 ms one-way delay 4. measure (average) one-way delay with 2 or more implementations,
using identical options and equal size large packets (e.g., 1400 octet IP payload)
5. observe that the increase measured in steps 2 and 4 is equivalent to the increase in ms expected due to the larger serialization time for each implementation. Most of the measurement errors in each system should cancel, if they are stationary.
10
3.2: First-bit to Last-bit, NetProbe
1400 byte payload 32 byte payload Delay for each mode (one mode) Delay Diff Expected Diff microseconds microseconds microseconds microseconds
1001621 1000356 1265 1094.4 1002735 1000356 2379 1094.4
TxDelay(us)
1000500
1001000
1001500
1002000
1002500
1003000
1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58
11
3.2: First-bit to Last-bit, NetProbe
Bi-modal delay behavior in the Network Emulator for UDP payload 96 octets & up Same for Poisson, Periodic, 1 sec, 10ms spacing Not evident in tests on the Management LAN
Delay increased with larger payload, but more than expected (170 us for low mode)
Suggestions to investigate further are welcomeTests on Management LAN, 100baseTx-FD 1400 byte payload 32 byte payload Ave Delay Ave Delay Diff Expected Diff microseconds microseconds microseconds microseconds
443.37 143.57 299.8 109.44 (190.36)
12
Other Examples One-way Delay, RFC 2679
This test is intended to evaluate measurements in sections 3 and 4 of [RFC2679].
Average delays before/after 2 second increase
Average pre-increase delay, microseconds 1000276.6 Average post 2s additional, microseconds 3000282.6 Difference (should be ~= Y = 2s) 2000006
Error Calibration, RFC 2679 This is a simple check to determine if an implementation reports the error
calibration as required in Section 4.8 of [RFC2679].
13
Summary Key clauses of RFC 2679 evaluated in Lab One Implementation: NetProbe Other volunteers? Comments on approach to reporting?
draft-morton-ippm-advance-metrics-01
What other RFCs should we target first?