Network Working Group Gabor Feher, BUTE
INTERNET-DRAFT Istvan Cselenyi, TRAB
Expiration Date: January 2002 Andras Korn, BUTE
July 2001
Benchmarking Methodology for Routers Supporting Resource Reservation
<draft-ietf-bmwg-benchres-method-00.txt>
1. Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
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This memo provides information for the Internet community. This memo
does not specify an Internet standard of any kind. Distribution of
this memo is unlimited.
2. Table of contents
1. Status of this Memo.............................................1
2. Table of contents...............................................1
3. Abstract........................................................2
4. Introduction....................................................2
5. Existing definitions............................................2
6. Methodology.....................................................3
6.1 Evaluating the Results......................................3
6.2 Test Setup..................................................3
6.2.1 Testing Unicast Resource Reservation Sessions..........5
6.2.2 Testing Multicast Resource Reservation Sessions........5
6.2.3 Signaling Flow.........................................6
6.2.4 Signaling Message Verification.........................6
6.3 Scalability Tests...........................................6
6.3.1 Maximum Signaling Message Burst Size...................7
6.3.2 Maximum Signaling Load.................................8
6.3.3 Maximum Session Load...................................9
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6.4 Benchmarking Tests.........................................11
6.4.1 Performing the Benchmarking Measurements..............12
7. Acknowledgement................................................14
8. References.....................................................14
9. Authors' Addresses:............................................15
3. Abstract
The purpose of this document is to define benchmarking methodology
measuring performance metrics related to IP routers supporting
resource reservation signaling. Apart from the definition and
discussion of these tests, this document also specifies formats for
reporting the benchmarking results.
4. Introduction
The IntServ over DiffServ framework [1] outlines a heterogeneous
Quality of Service (QoS) architecture for multi domain Internet
services. Signaling based resource reservation (e.g. via RSVP [2]) is
an integral part of that model. While this significantly lightens the
load on most of the core routers, the performance of border routers
that handle the QoS signaling is still crucial. Therefore network
operators, who are planning to deploy this model, shall scrutinize
the scalability limitations in reservation capable routers and the
impact of signaling on the forwarding performance of the routers.
An objective way for quantifying the scalability constraints of QoS
signaling is to perform measurements on routers that are capable of
resource reservation. This document defines a specific set of tests
that vendors or network operators can use to measure and report the
signaling performance characteristics of router devices that support
resource reservation protocols. The results of these tests will
provide comparable data for different products supporting the
decision process before purchase. Moreover, these measurements
provide input characteristics for the dimensioning of a network in
which resources are provisioned dynamically by signaling. Finally,
these tests are applicable for characterizing the impact of control
plane signaling on the forwarding performance of routers.
This benchmarking methodology document is based on the knowledge
gained by examination of (and experimentation with) several very
different resource reservation protocols: RSVP [2], Boomerang [3],
YESSIR [4], ST2+ [5], SDP [6], Ticket [7] and Load Control [8].
Nevertheless, this document aspires to compose terms that are valid
in general and not restricted to these protocols.
5. Existing definitions
A previous document, "Benchmarking Terminology for Routers Supporting
Resource Reservation" [9] defines performance metrics and other terms
that are used in this document. To understand the test methodologies
defined here, that terminology document must be consulted first.
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6. Methodology
6.1 Evaluating the Results
RFC2544 [10] describes considerations regarding the implementation
and evaluation of benchmarking tests, which are certainly valid for
this test suite also. Namely, the authors intended to create a system
from commercially available measurement instruments and devices for
the sake of easy implementation of the described tests. Simple test
scripts and benchmarking utilities for Linux are publicly available
from the Boomerang homepage [11].
During the benchmarking tests, care should be taken for selecting the
proper set of tests for a specific router device, since not all of
the tests applicable to a particular Devices Under Test (DUT).
Finally, the selection of the relevant measurement results and their
evaluation requires experience and it must be done with an
understanding of generally accepted testing practices regarding
repeatability, variance and statistical significance of small numbers
of trials.
6.2 Test Setup
The ideal way to perform the measurements is to connect a passive
tester device (or, in short, passive tester) to all network
interfaces of the DUT, enabling the tester to capture all signaling
and data traffic that enters into or leaves from the DUT. Based on
the captured data packets and signaling messages along with the
proper time stamps the investigated performance metrics can be
computed. In addition to the passive tester there are signaling and
data traffic end-points that are responsible to generate and
terminate the required signaling and data flows going through the
DUT. These flows are used to generate router load in the DUT and the
measurements are also performed using them. This scenario is
illustrated in Figure 1.
Probably, the best solution is to connect the tester via network
traffic repeater devices (e.g. hubs) to the network interfaces of the
DUT. These repeaters cause very small delay in the ongoing packets,
and therefore their effect is insignificant in the measurements.
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+------------+
| |
+--->| Passive |<---+
| | tester | |
| +------------+ |
| |
+---------------+ | +------------+ | +---------------+
| Signaling and | | | | | | Signaling and |
| data traffic |----+--->| DUT |----+--->| data traffic |
| end-point | | | | end-point |
+---------------+ +------------+ +---------------+
Figure 1
Moreover, tester devices should not have to be passive during the
measurement, rather they can generate the signaling and data flows as
well. This way the signaling and data traffic end-point and the
traffic capturing device can be combined into a single tester device,
called active tester. In this case the signaling and traffic flow,
the initiator tester device is the driver of the input network
interfaces of the DUT, while the second one, the signaling and
traffic terminator tester device is connected to the output network
interfaces of the tested device and captures signaling messages and
data packets leaving the DUT. Figure 2 shows this scenario.
+---------------+ +-----------+ +---------------+
| | | | | |
| Active tester |----->| DUT |----->| Active tester |
| | | | | |
+---------------+ +-----------+ +---------------+
Figure 2
In this scenario, the performance metrics are calculated from the log
of initiated packets and their initiation time in the first active
tester device and the log of captured packets and their capture time
in the second active tester. Obviously, the measurements do worth
nothing if the two testers are not clock-synchronized, since the
difference of the packet initiation times and packet capture times is
biased by the clock skew of the testers. For this reason, the clock
of the testers must be synchronized before the measurements are
performed. Nevertheless, scalability tests do not depend on the clock
synchronization and therefore they can be performed without any
preparation on the testers.
It is also possible to use only one active tester, which is the
signaling and traffic flow initiator and terminator device in the
same time. Although, this way the clock synchronization problem can
be avoided, but the tester should be powerful enough to generate and
capture all the test flows required by the measurements.
During the benchmarking tests, if the clocks are properly
synchronized when it is necessary, each test configuration is
suitable for the measurements. For this reason, we have not defined
different test methodologies for each test scenarios. Instead, we use
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terms "initiator tester" and "terminator tester", which have their
equivalent appliances in each test configuration.
Initiator tester is the device that generates the signaling and data
flows, while terminator tester is the device that terminates the
signaling and data flow. In addition, the performance metrics
measurement is also performed by the tester(s). Evidently, in the
case of the configuration, where there is only one active tester, the
initiator tester and the terminator tester is the same appliance.
6.2.1 Testing Unicast Resource Reservation Sessions
Testing unicast resource reservation sessions requires that the
initial tester is connected to one of the network interfaces of the
DUT and the terminator tester is connected to a different network
interface of the tested device.
During the benchmarking tests, the initiator tester must use unicast
addresses for data traffic flows and the resource reservation
requests must refer to unicast resource reservation sessions. In
order to be able to compute the performance metrics, all data packets
and signaling messages transmitted by the DUT must be perceivable for
the tester.
6.2.2 Testing Multicast Resource Reservation Sessions
Testing multicast resource reservation sessions requires the initial
tester to be connected to more than one network interfaces of the
DUT, while the terminator tester is connected to more than one
network interfaces of the tested device whose interfaces are
different from the previous ones.
Furthermore, during the measurements, the data traffic flows
originated from the initiator tester must be sent to multicast
addresses and the reservation sessions must refer to one or more of
the multicast flows. Of course, just like in the case of unicast
resource reservation sessions, all data packets and signaling
messages transmitted by the DUT must be perceivable for the tester.
Since there are protocols supporting more than one resource
reservation schemes for multicast reservations (e.g. RSVP SE/FF/WF);
and in a view of the fact that the number of incoming and outgoing
network interface combinations of the DUT might be almost countless;
the benchmarking tests, described here, do not require measuring all
imaginable setup situation. Still, routers supporting multicast
resource reservations must be tested against the performance metrics
and scalability limits on at least one multicast scenario. Moreover,
there is a suggested multicast test configuration that consists of a
multicast group with four signaling end-points including one traffic
originator and three traffic destinations residing on different
network interfaces of the DUT.
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The benchmarking test reports taken on DUTs supporting multicast
resource reservation sessions always have to contain the proper
multicast scenario description.
6.2.3 Signaling Flow
This document often refers to signaling flows. A signaling flow is
sequence of signaling messages.
In the case of the measurements defined in this document there are
two types of signaling flows: First, there is a signaling flow that
is constructed from signaling primitives of the same type. Second,
there is a signaling flow that is constructed from signaling
primitive pairs. Signaling primitive pairs are needed in situations
where one of the signaling primitive alters the states of the DUT,
but the test demand constant DUT conditions during the test. In this
case, to avoid the effect of the state modification, the second
signaling primitive should restore the states modification in the
DUT. A typical example for the second type of signaling flow is a
flow of alternating reservation set-up and tear-down messages.
Moreover, the signaling messages should be equally spaced on the time
scale when they are forming a signaling flow. This is mandatory in
order to obtain measurements that can be repeated later. Since modern
resource reservation protocols are designed to avoid message
synchronization, thus, equally spaced signaling messages are not
unrealistic in the real life.
The signaling flow is characterized with the type of the signaling
primitive or the pair of signaling primitives along with the period
time of the signaling messages.
6.2.4 Signaling Message Verification
Although, the conformance testing of the resource reservation is
beyond the scope of this document, defective signaling message
processing can be expected in an overloaded router. Therefore, during
the benchmarking tests, when signaling messages are processed in the
DUT, the terminator device must validate the messages whether they
are fully conform to the message format of the resource reservation
protocol specification and whether they are the expected signaling
messages at the given situation. If any of the messages are against
the protocol specification then the benchmarking test report must
indicate the situation of the failure.
Verifying data traffic packets are not required, since the signaling
performance benchmarking of reservation capable routers should not
deal with data traffic. For this purpose there are other benchmarking
methodologies that verify data traffic during the measurements, like
the one described in RFC 2544.
6.3 Scalability Tests
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Scalability tests are defined to explore the scalability limits of a
reservation capable router. This investigation focuses on the
scalability limits related only to signaling message handling and
therefore examination of the data forwarding engine is out of the
scope of this document.
6.3.1 Maximum Signaling Message Burst Size
Objective:
Determine the maximum signaling burst size, which is the number of
the signaling messages in a signaling burst that the DUT is able to
handle without signaling loss.
Procedure:
1. Select a signaling primitive or a signaling primitive pair and
construct a signaling flow. The signaling messages should follow each
other back-to-back in the flow and after "n" number of messages the
flow should be terminated. In the first test sequence the number "n"
should be set to one.
Additionally, all the signaling messages in the signaling flow must
conform to the resource reservation protocol definition and must be
parameterized in a way to avoid signaling message processing errors
in the DUT.
2. Send the signaling flow to the DUT and count the signaling
messages received by the terminator tester.
3. When the number of sent signaling messages ("n") equals to the
number of received messages, then the number of messages forming the
signaling flow ("n") should be increased by one; and the test
sequence has to be repeated. However, if the receiver receives less
signaling messages than the number of sent messages, it indicates
that the DUT is beyond its scalability limit. The measured
scalability limit for the maximum signaling message burst size is the
length of the signaling flow in the previous test sequence ("n"-1).
In order to avoid transient test failures, the whole test must be
repeated at least 30 times and the report should indicate the median
of the measured maximum signaling message burst size values as the
result of the test. Among the test runs, the DUT should be reset to
its initial state.
There are signaling primitives, such as signaling messages indicating
errors, which are not suitable for this kind of scalability tests.
However, each signaling primitive suitable for the test should be
investigated.
Reporting format:
The report should indicate the type of the signaling primitive or
signaling primitive pair and the determined maximum signaling message
burst size.
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Note:
In the case of routers supporting multicast resource reservation
sessions, the signaling burst can be also constructed by sending
signaling messages to multiple network interfaces of the DUT at the
same time.
6.3.2 Maximum Signaling Load
Objective:
Determine the maximum signaling load, which is the maximum number of
signaling messages within a time unit that the DUT is able to handle
without signaling loss.
Procedure:
1. Select a signaling primitive or a signaling primitive pair and
construct a signaling flow. The period of the signaling flow should
be adjusted in a way that exactly "s" signaling messages arrive
within one second. In the first test sequence the number "s" should
be set to one (i.e. 1 message per second).
Additionally, all the signaling messages in the signaling flow must
conform to the resource reservation protocol definition and must be
parameterized in a way to avoid signaling message processing errors
in the DUT.
2. Send the signaling flow to the DUT for at least one minute, and
count the signaling messages received by the terminator tester.
3. When the number of sent signaling messages ("s" times the duration
of the signaling flow) equals to the number of received messages, the
signaling flow period should be decreased in a way that one more
signaling message fits into a one second interval of the signaling
flow ("s" should be increased by one). But, if the receiver receives
less signaling messages than the number of sent messages, it
indicates that the DUT is beyond its scalability limit. The measured
scalability limit for the maximum signaling load is the number of
signaling messages fitting into one second of the signaling flow in
the previous test sequence ("s"-1).
In order to avoid transient test failures, the whole test must be
repeated at least 30 times and the report should indicate the median
of the measured maximum signaling load values as the result of the
test. Among the test runs, the DUT should be reset to its initial
state.
In the case of this test, there are also signaling primitives which
are not suitable for this kind of scalability tests. However, each
signaling primitive that is suitable for the test should be
investigated just like in the case of the maximum signaling burst
size test.
Reporting format:
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The report should indicate the type of the signaling primitive or
signaling primitive pair and the determined maximum signaling load
value.
6.3.3 Maximum Session Load
Objective:
Determine the maximum session load, which is the maximum number of
resource reservation sessions that can be maintained simultaneously
in a reservation capable router. The maximum number of session relies
on two architectural components of the DUT. First, the DUT should
have enough memory space to store the attributes of the different
resource reservation sessions. Second, the DUT has to be powerful
enough to maintain all the reservation sessions if they require
actions during the lifetime of the sessions.
In the case of hard-state protocols we cannot speak of reservation
session maintenance, therefore in this situation the available memory
space is the only limit for the session number. Moreover, there are
also resource reservation protocols that handle only the aggregates
of reservation sessions (e.g. Load Control [8]) and do not
distinguish the separate traffic flows referring to reserved
resources. Of course, in this situation there is no session
maintenance either, since there are no reservation sessions, plus the
memory allocation for the aggregates is limited. In this latter case,
the maximum session load is defined to be unlimited and the test can
be skipped.
According to the dual limits of the measurement, the benchmarking
procedure is separated into two tests. The first test investigates
the session number limit due to the memory space, while the second
test explores the reservation session maintenance capability of the
DUT.
The first test is applied to every resource reservation protocol,
which stores reservation sessions separately and not only an
aggregate of them. Resource reservation protocols that are capable
for session aggregation, but still have the capability to handle
separate sessions (e.g. Boomerang [3]) are still subject of this
test.
Procedure:
1. Set up a reservation session in the reservation capable router by
sending the appropriate signaling messages to the DUT.
2. Establish one more reservation session in the DUT using the
appropriate signaling messages. In the case of soft-state protocols,
all the reservation sessions existing in the DUT must be maintained
using refresh messages.
3. Repeat step 2 until the router signs that there is not enough
memory space to establish the new reservation session. In this case,
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the test is finished and the maximum memory capacity available to
store the sessions is reached.
Note:
Not all the resource reservation protocols support to signal the
overrun of the maximum memory capacity limit directly. However,
certain behavior of the router may also indicate the memory overrun.
The second test is applied to those resource reservation capable
routers only that run reservation session maintenance mechanisms to
refresh internal states belonging to reservation sessions. Here, we
investigate the DUT whether it is able to cope with the refresh
signaling message handling that shows also the capability to refresh
the internally stored reservation sessions.
Procedure:
1. Set up "n" number of reservation session in the reservation
capable router by sending the appropriate signaling messages to the
DUT. In the first test sequence the number "n" should be set to one.
Beside the reservation session generation, the initiator tester must
also take care of the reservation session refreshes.
2. Capture the refresh signaling messages leaving the DUT for a
specified amount of time ("T") while still maintaining the
established reservations with refresh signaling messages. Time "T"
must be at least as long as the protocol specifies as reservation
time out.
3. Check whether each reservation session is refreshed during the
refresh period that was examined in step 2. The proof of the session
refresh is a leaving refresh signaling message referring to the
corresponding reservation session. If all sessions that were set up
in step 1 are refreshed during step 2, then repeat the test sequence
by increasing the number of reservations by one ("n"+1). However,
when any of the reservations was dropped by the DUT, then the test
sequence should be cancelled and the determined maximum session load
is the number of resource reservation sessions maintained
successfully in the previous test sequence ("n"-1).
In order to avoid transient test failures, the whole test must be
repeated at least 30 times and the report should indicate the median
of the measured maximum signaling load values as the result of the
test. Among the test runs, the DUT should be reset to its initial
state.
Reporting format:
The report should indicate determined maximum session load value,
which is the lowest value between the two test results.
Note:
When the number of reserved sessions grows over a number that counts
to a very high value in the given technology conditions, then the
test can be canceled and the report can state that the resource
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reservation protocol implementation performs the maximum number of
reservation sessions over that limit (e.g. "Over 100.000 sessions").
Also note, that testing the DUT in the case of multicast and unicast
scenario, it may result different maximum session load values.
6.4 Benchmarking Tests
Benchmarking tests are defined to measure the QoS signaling related
performance metrics on the resource reservation capable router
device.
Since the objective of the benchmarking is to characterize routers
performing resource reservation in real-life situations, therefore
during the tests the DUT must not bump into its scalability limits
determined by the previous test.
Each performance metric is measured when the DUT is under different
router load conditions. The router load is generated and
characterized using combinations of independent load types:
a. Signaling load
b. Session load
c. Premium traffic load
d. Best-effort traffic load
The initiator tester device generates the signaling load on the DUT
by sending a signaling flow to the terminator tester. This signaling
flow is constructed from a specific signaling primitive or a
signaling primitive pair and has the appropriate period parameter.
The session load is generated by the signaling end-points setting up
resource reservation sessions in the DUT via signaling. In the case
of soft-state protocols, the initiator tester device must also
maintain the reservation sessions with refresh signaling messages
periodically.
The initiator tester device generates the premium traffic load by
sending a data traffic flow to the terminator tester across the DUT.
This traffic flow should have dedicated resourced in the DUT, set up
previously using signaling messages. The traffic must consist of
equally spaced and equally sized data packets. Although any transfer
protocol is suitable for traffic generation, it is highly recommended
to use UDP packets, since this data flow is totally controllable,
unlike TCP that uses congestion avoidance mechanism. The premium
traffic must be characterized by its traffic parameters: data packet
size in octets, the calculated bandwidth of the stream in kbps unit
and the transfer protocol type. The data packet size should include
both the payload and the header of the IP packet.
The initiator tester device generates the best-effort traffic load by
sending a data traffic flow (that refers to no resource reservation
sessions) to the terminator tester across the DUT. Any other
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attributes of the traffic flow must meet the conditions described
previously in the case of premium traffic load.
Note, that these four load types have influence on each other from
their nature that may spoil the measurements. Therefore, in order to
have accurate results these cross-effects must be minimized during
the benchmarking tests. The signaling load can cause interference
with the session load, when certain signaling messages alter the
number of reservation session in the DUT. To cancel this influence
the signaling flow should contain signaling message pairs, where the
message pairs has opposite effect restoring the changes caused in the
DUT. On the other hand, in the case of soft-state protocols, sessions
must be refreshed by periodically sent signaling messages. Although
refresh messages are used to maintain the reservation sessions, still
they are counted as signaling messages. Furthermore, signaling
messages are realized as data packets. Such way signaling messages
must be taken into account in the traffic flow calculation as well.
6.4.1 Performing the Benchmarking Measurements
Objective:
The goal is to take measurements on the DUT running a resource
reservation protocol implementation in the case of different load
conditions. The load on the DUT is always the combination of the four
load components described before.
Procedure:
The procedure is to load the router with each load component at a
desired level and measure the investigated performance metrics. The
load condition on the DUT should not change during the test. Once,
the measurement is complete, repeat the test with different load
distributions.
During the test sequences, in order to avoid transient flow behavior
influencing the measurements, the measurements should begin after a
delay of at least "T" time and after the setup of the common load on
the DUT. The value of "T" depends on the parameters of the load
components and the resource reservation protocol implementations,
but, as a rule of thumb, it should be enough for at least 10 packets
from the traffic flows and 10 signaling messages from the signaling
flow to pass through the DUT and at least one refresh period to
expire in the case of soft-state protocols.
During the measurement of the performance metrics in a practical load
setup, not just one, but 100 measurement samples should be collected.
Normally, the empirical distribution function of the tests is similar
to the curve of a Gaussian distribution, and therefore the modus and
the median are in the same location. Such case, the result of the
test sequence is the median of the samples. In the case of different
shaped empirical distribution functions, the curve must be further
analyzed and the result should describe the curve well enough.
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In order to avoid transient test run failures that may cause invalid
results for the entire test, the whole test must be repeated at least
10 times and the report should indicate the median of the measured
values filtering out the extreme results. Moreover, after each test
run the DUT should be reset to its initial state.
In order to perform a complete benchmarking test, every performance
metrics must be measured using signaling flows made of every
applicable signaling primitives or primitive pairs.
Since the test methodology is the same for all the different
performance metric benchmarking procedure, it is also recommended to
perform the measurements for all performance metrics at the same time
in one test cycle.
At first sight, this procedure may look easy to carry out, but in
fact there are lots of difficulties to overcome. The following
guidelines may help in reducing the complexity of creating a
conforming measurement setup.
1. It is reasonable to define different amounts for each load
component (load levels) before benchmarking and then measure the
performance metrics with all possible combinations of these
individual load levels.
2. The number of different load combinations depends on the number of
different load levels defined for a load component. Working with too
much number of load levels is very time-consuming and therefore not
suggested. Instead, there are proposed levels and parameters for each
load component.
The data traffic parameters for the traffic load components have to
be selected from generally used traffic parameters. It is recommended
to choose a packet size of: 54, 64, 128, 256, 1024, 1518, 2048 and
4472 bytes (these are the same values that are used in RFC 2544 that
introduces methodology for benchmarking network interconnect
devices). Additionally, the size of the packets should always remain
below the MTU of the network segment. The packet rate is recommended
to be one of 0, 10, 500, 1000 or 5000 packets/s. Since the number of
combinations for these traffic parameters is still large, the highly
recommended values are 64, 128 and 1024 bytes for the packet size and
10 and 1000 packets/s packet rate. These values adequately represent
a wide range of traffic types common in today's Internet.
The number of session load levels should be at least 4 and it is
recommended to share them equally between 0 and the maximum session
load value.
The number of signaling load levels should be at least 4 as well, and
the actual value of the signaling load is also recommended to be
equally distributed between 0 and the maximum signaling load value.
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Zero load level means that the actual load component is not involved
in the router load.
Reporting format:
As the whole report description requires a four-dimension table (four
load components plus the results), which is hard to visualize for a
human being, therefore the results are extracted into ordinary two-
dimensional tables. Each table has two fixed load component
quantities and the other two load component levels are the row and
column for the table. Such way, one set of such tables describe the
benchmarking results for one certain type of signaling flow used in
the generation of the signaling load. Naturally, each different
signaling flow requires separate tables.
Note:
Of course in the case of multicast resource reservation sessions, the
combination number of the different multicast scenarios multiplies
the number benchmarking tests also.
7. Acknowledgement
The authors would like to thank the following individuals for their
help in forming this document: Norbert Vegh and Anders Bergsten from
Telia Research AB, Sweden, Krisztian Nemeth, Peter Vary, Balazs Szabo
and Gabor Kovacs from High Speed Networks Laboratory of Budapest
University of Technology and Economics.
8. References
[1] Y. Bernet, et. al., "A Framework For Integrated Services
Operation Over Diffserv Networks", Internet Draft, work in
progress, May 2000, <draft-ietf-issll-diffserv-rsvp-05.txt>
[2] B. Braden, Ed., et. al., "Resource Reservation Protocol (RSVP) -
Version 1 Functional Specification", RFC 2205, September 1997.
[3] J. Bergkvist, I. Cselenyi, D. Ahlard, "Boomerang - A Simple
Resource Reservation Framework for IP", Internet Draft, work in
progress, November 2000, <draft-bergkvist-boomerang-framework-
00.txt>
[4] P. Pan, H. Schulzrinne, "YESSIR: A Simple Reservation Mechanism
for the Internet", Computer Communication Review, on-line
version, volume 29, number 2, April 1999
[5] L. Delgrossi, L. Berger, "Internet Stream Protocol Version 2
(ST2) Protocol Specification - Version ST2+", RFC 1819, August
1995
[6] P. White, J. Crowcroft, "A Case for Dynamic Sender-Initiated
Reservation in the Internet", Journal on High Speed Networks,
Special Issue on QoS Routing and Signaling, Vol 7 No 2, 1998
Feher, Cselenyi, Korn Expires January 2002 [Page 14]
INTERNET-DRAFT <draft-ietf-bmwg-benchres-method-00.txt> July 2001
[7] A. Eriksson, C. Gehrmann, "Robust and Secure Light-weight
Resource Reservation for Unicast IP Traffic", International WS
on QoS'98, IWQoS'98, May 18-20, 1998
[8] L. Westberg, Z. R. Turanyi, D. Partain, Load Control of Real-
Time Traffic, A Two-bit Resource Allocation Scheme, Internet
Draft, work in progress, April 2000, <draft-westberg-loadcntr-
03.txt>
[9] G. Feher, I. Cselenyi, A. Korn, "Benchmarking Terminology for
Routers Supporting Resource Reservation", Internet Draft, work
in progress, July 2001, <draft-ietf-bmwg-benchres-term-00.txt>
[10] S. Bradner, J. McQuaid, "Benchmarking Methodology for Network
Interconnect Devices", RFC 2544, March 1999
[11] Boomerang Team, "Boomerang homepage - Benchmarking Tools",
http://boomerang.ttt.bme.hu
9. Authors' Addresses:
Gabor Feher
Budapest University of Technology and Economics (BUTE)
Department of Telecommunications and Telematics
Pazmany Peter Setany 1/D, H-1117, Budapest,
Phone: +36 1 463-3110
Email: feher@ttt-atm.ttt.bme.hu
Istvan Cselenyi
Telia Research AB
Vitsandsgatan 9B
SE 12386, Farsta
SWEDEN,
Phone: +46 8 713-8173
Email: istvan.i.cselenyi@telia.se
Andras Korn
Budapest University of Technology and Economics (BUTE)
Institute of Mathematics, Department of Analysis
Egry Jozsef u. 2, H-1111 Budapest, Hungary
Phone: +36 1 463-2475
Email: korn@math.bme.hu
Feher, Cselenyi, Korn Expires January 2002 [Page 15]
