Internet DRAFT - draft-baillargeon-ippm-twamp-value-added-octets
draft-baillargeon-ippm-twamp-value-added-octets
Network Working Group S. Baillargeon
INTERNET-DRAFT C. Flinta
Intended Status: Informational A. Johnsson
Expires: July 24, 2012 S. Ekelin
Ericsson
January 24, 2012
TWAMP Value-Added Octets
draft-baillargeon-ippm-twamp-value-added-octets-03.txt
Status of This Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Abstract
This memo describes optional extensions to the TWAMP test protocol
for identifying and managing packet trains, which enables measuring
capacity metrics like the available path capacity, tight section
capacity and UDP delivery rate in the forward and reverse path
directions.
Status of this Memo
This Internet-Draft is submitted to IETF in full conformance with the
provisions of BCP 78 and BCP 79.
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Copyright and License Notice
Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
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include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
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Table of Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1 Requirements Language . . . . . . . . . . . . . . . . . . . 4
2 Purpose and scope . . . . . . . . . . . . . . . . . . . . . . . 4
3 Capacity Measurement Principles . . . . . . . . . . . . . . . . 5
4 TWAMP Control Extensions . . . . . . . . . . . . . . . . . . . . 6
5 Extended TWAMP Test . . . . . . . . . . . . . . . . . . . . . . 7
5.1 Sender Behavior . . . . . . . . . . . . . . . . . . . . . . 7
5.1.1 Packet Timings . . . . . . . . . . . . . . . . . . . . 7
5.1.2 Session-Sender Packet Format . . . . . . . . . . . . . 7
5.2 Reflector behavior . . . . . . . . . . . . . . . . . . . 12
5.2.1 Session-Reflector Packet Format . . . . . . . . . . 13
5.3 Additional Considerations . . . . . . . . . . . . . . . . 14
6 Security Considerations . . . . . . . . . . . . . . . . . . . 14
7 IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
8 References . . . . . . . . . . . . . . . . . . . . . . . . . . 15
8.1 Normative References . . . . . . . . . . . . . . . . . . 15
8.2 Informative References . . . . . . . . . . . . . . . . . 15
Author's Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
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1 Introduction
The notion of embedding a number of meaningful fields in the padding
octets has been established as a viable methodology for carrying
additional information within the TWAMP-Test protocol running between
a Session-Sender and a Session-Reflector [RFC5357] [RFC6038].
This memo describes an extension to the Two-Way Active Measurement
Protocol [RFC5357]. It is called the Value-Added Octets feature.
This feature enables the controller host to measure capacity metrics
like the IP-type-P available path capacity (APC) [RFC5136], IP-layer
tight section capacity (TSC) [Y1540] and UDP delivery rate (e.g. as
defined in [RFC1242]) on both forward and reverse paths using a
single TWAMP test session with symmetrical or asymmetrical test
packet sizes. The actual method to calculate the APC, TSC or the UDP
delivery rate from packet-level data performance data is not
discussed in this memo.
The Valued-Added Octets feature consists of new behaviors for the
Session-Sender and Session-Reflector, and a set of value-added octets
of information that are placed at the beginning of the Packet Padding
field [RFC5357] or at the beginning of the Packet Padding (to be
reflected) field [RFC6038] by the Session-Sender, and are reflected
or returned by the Session-Reflector. The length of the value-added
octets (version 1) is 14 octets.
1.1 Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
2 Purpose and scope
The purpose of this memo is to describe the Valued-Added Octets
feature for TWAMP [RFC5357].
The scope of the memo is limited to specifications of the following
enhancements:
o The definition of a structure for embedding a sequence of
value-added fields at the beginning of the Packet Padding field
[RFC5037] or Packet Padding (to be reflected) field [RFC6038]
in the TWAMP test packets and,
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o The definition of new Session-Sender and Session-Reflector
behaviors
The motivation for this feature is to enable the measurements of
capacity metrics on both the forward and reverse paths with
symmetrical or asymmetrical test packet sizes.
This memo does not extend the modes of operation through assignment
of a new value in the Modes field (see Section 3.1 of [RFC4656] for
the format of the Server Greeting message). However a new mode is
required to communicate feature capability and use in an
interoperable manner. For instance, when the Server and Control-
Client have agreed to use the Value-Added Octets Version 1 mode
during control connection setup, then the Control-Client, the Server,
the Session-Sender, and the Session-Reflector must all conform to the
requirements of that mode, as identified below.
The packet padding octets are designed to retain backward
compatibility with the original TWAMP test protocol [RFC5357].
3 Capacity Measurement Principles
Most capacity estimation methods for APC [RRBNC][PDM][ENHJMMB][SBW]
and for UDP delivery rate need to send and receive packets in groups,
called packet trains or simply trains. Each train is sent at a
specific transmission rate in a given direction. These trains must be
identified within each bi-directional test session stream.
The first measurement principle is to send multiple trains within a
test session stream from one IP node to another IP node in order to
estimate the APC, TSC or UDP delivery rate in the forward direction.
Each train consists of a group of test packets which are separated
from each other by a packet interval, as shown in the picture below.
The packet interval is measured using either the first bit or the
last bit of two consecutive packets.
tt tt tt
|<---------->| |<---------->| |<---------->|
| | | | | |
+------------+ +------------+ +------------+
| Packet 1 | | Packet 2 | | Packet 3 |
+------------+ +------------+ +------------+
| | |
|<--------------------->|<--------------------->|
packet interval 1 packet interval 2
The test packet size and interval between consecutive packets for
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each train sent by the Session-Sender and reflected by the Session-
Reflector MUST be calculated and determined by the controller or an
application or entity communicating with the controller. The packet
size and interval MAY vary within a train, between trains and MAY
also be different depending on forward or reverse transmission
direction. Determination of the packet size and interval is
implementation-specific.
The transmission time tt to send one packet (i.e. determined by the
interface speed and the IP packet size) is also shown in the picture.
Observe that the packet interval MUST be larger than or equal to tt.
At the Session-Reflector, each received test packet within a forward
train is time stamped. This provides a second set of packet interval
values. Methods for measuring the APC, TSC and UDP delivery rate use
the packet intervals obtained from both end points in the estimation
process. The method to measuring the UDP delivery rate may also
require the packet loss at the receiving end. The estimation process
itself as well as any requirements on software or hardware is
implementation-specific.
The second measurement principle is referred to as self-induced
congestion. According to this principle, in order to measure APC, TSC
and UDP delivery rate, some trains MUST cause momentary congestion on
the network path. In essence this means that some trains MUST be sent
at a higher rate than what is available on the network path.
In order to fulfill the above measurement principles and to measure
the APC, TSC and UDP delivery rate in the reverse direction, the test
packets at the Session-Reflector MUST be re-grouped into trains and
then transmitted back to the Session-Sender with a provided packet
interval.
4 TWAMP Control Extensions
TWAMP-Control protocol [RFC5357] uses the Modes field to identify and
select specific communication capabilities, and this field is a
recognized extension mechanism.
TWAMP connection establishment follows the procedure defined in
Section 3.1 of [RFC4656] and Section 3.1 of [RFC5357]. For
interoperability, the Value-added octet feature require one new bit
position (and value) to identify the ability of the Server/Session-
Reflector to read and act upon the new fields in the value-added
octets. Such bit position (and value) is not defined in this memo.
Both the Reflect Octets mode and Symmetrical Size mode MAY be
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selected to ensure the reflection of the value-added padding octets
by the Session-Reflector and symmetrical size TWAMP-Test packets in
the forward and reverse directions of transmission.
5 Extended TWAMP Test
The forward and reverse APC, TSC and UDP delivery rate measurement
characteristics depend on the size and packet intervals of the test
packets. This memo allows variable packet sizes and packet intervals
between trains in different transmission directions, trains in the
same transmission direction and even between packets in the same
train. The functionality is described below.
The TWAMP-test protocol carrying the value-added padding octets is
identical to TWAMP [RFC5357] except for the definition of first 14
octets in Packet Padding that the Session-Sender expects to be
reflected. The new octets define fields for Value-Added Octets
Version, Flags, Last Sequence Number in Train, Desired Reverse Packet
Interval and Desired Reverse Padding Length. Each of these fields are
described in detail below.
The Session-Sender and Session-Reflector behaviors are also modified.
5.1 Sender Behavior
This section describes the extensions to the behavior of the TWAMP
Session-Sender.
5.1.1 Packet Timings
The Send Schedule is not utilized in TWAMP and this is unchanged in
this memo.
5.1.2 Session-Sender Packet Format
The Session-Sender packet format follows the same procedure and
guidelines as defined in TWAMP [RFC5357] and TWAMP Reflect Octets and
Symmetrical Size Features [RFC6038].
This feature allows the Session-Sender to set the first few octets in
the TWAMP-Test Packet Padding field with information to communicate
value-added padding version number, flag bits, sequence number of the
last packet in a train, desired reverse packet interval (or per-
packet waiting time) and desired reverse padding length for the
reverse path direction of transmission.
A version number and a sequence of flag bits are defined at the very
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beginning of the value-added padding octets. The version number
identifies the version of the value-added padding octets and meaning
of the flag bits and corresponding fields. Each flag bit indicates if
a specific field is used in the valued-added padding octets. The
version number and flag bits provide an effective method for
extracting information at Session-Reflector and Session-Sender. This
document defines version 1 with three flag bits: L, I and P.
The format of the test packet depends on the TWAMP mode and flag bits
being used. The Value-Added Octets Version 1 mode is intended to work
with any TWAMP modes.
The Session-Sender SHALL use the following TWAMP test packet format
when the Value-Added Octets Version 1 is selected in conjunction with
the unauthenticated mode:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Timestamp |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Error Estimate | Ver |L|I|P| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Last Seqno In Train |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Desired Reverse Packet Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Desired Reverse Padding Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-|
| Additional Packet Padding |
. .
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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The Session-Sender SHALL use the following TWAMP test packet format
when the Value-Added Octets Version 1 is selected in conjunction with
the unauthenticated mode, Symmetrical Size mode and Reflect Octets
mode:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Timestamp |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Error Estimate | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| |
| |
| MBZ (27 octets) |
| |
| |
| |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | Ver |L|I|P| Reserved | Last... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Seqno in Train | Desired... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reverse Packet Interval | Desired... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reverse Padding Length | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| Additional Packet Padding |
. .
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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The Session-Sender SHALL use the following TWAMP test packet format
when the Value-Added Octets Version 1 is selected in conjunction with
the unauthenticated mode, Symmetrical Size mode and Reflect Octets
mode with a non-zero value in the Server octets field:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Timestamp |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Error Estimate | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| |
| |
| MBZ (27 octets) |
| |
| |
| |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | Server octets | Ver |L|I|P| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | Last Seqno in Train |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | Desired Reverse Packet Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | Desired Reverse Padding Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | Additional Packet Padding |
+-+-+-+-+-+-+-+-+ |
| |
. .
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
In the mode using Reflect Octets illustrated above, the value-added
padding octets are embedded in the Packet Padding (to be reflected)
field.
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The Version (Ver) field MUST be encoded in the first 4 bits. It
identifies the version number of the value-added padding octets and
meaning of the flag bits and the corresponding fields. This memo
defines version 1. When the Value-Added Octets Version 1 mode is
selected, the Session-Sender MUST set the Ver field to 1.
The 3 bits after the Version field are used for flags: L, I and P.
The Last Seqno in Train bit (L) is the first flag. When the Value-
Added Octets Version 1 mode is selected, the Session-Sender MAY set
the Last Seqno in Train bit L to 1.
The Desired Reverse Packet Interval bit (I) is the second flag. When
the Value-Added Octets Version 1 mode is selected, the Session-Sender
MAY set the Desired Reverse Packet Interval bit I to 1.
The Desired Reverse Padding Length bit (P) is the third flag. When
the Value-Added Octets Version 1 mode is selected, the Session-Sender
MAY set the Desired Reverse Padding Length bit P to 1.
The Reserved field is reserved for future use. All 9 bits of the
Reserved field MUST be transmitted as zero by the Session-Sender.
If the Last Seqno in Train bit is set to 1, then the Last Seqno in
Train field MUST contain an unsigned 32 bit integer generated by the
Session-Sender. It MUST indicate the expected sequence number of the
last packet in the train. It SHOULD be used by the Session-Sender and
Session-reflector to identify the train a test packet belongs to. The
packets belonging to a train are determined by observing the test
packet sequence number in relation to the Last Seqno for a train. The
Last Seqno in Train MUST be higher or equal to the sequence number of
the packet. It must also be higher than the Last Seqno in Train for
the previous train. If the L bit is set to 0, the Session-Sender
shall set all the bits in the Last Seqno in Train field to zero.
If the Desired Reverse Packet Interval bit is set to 1, then the
Desired Reverse Packet Interval field MUST contain an unsigned 32 bit
integer generated by the Session-Sender. It MUST indicate the desired
packet interval (or the waiting time) that the Session-Reflector
SHOULD use when transmitting the reflected test packets towards the
Session-Sender. The value 0 means the The Session-Reflector SHOULD
return the test packet to the Session-Sender as quickly as possible.
The format of this field MUST be a fractional part of a second as
defined in OWAMP [RFC4656]. If I bit is set to 0, the Session-Sender
shall set all the bits in the Desired Reverse Packet Interval field
to zero.
If the Desired Reverse Padding Length bit is set to 1, then the
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Desired Reverse Padding Length field MUST contain an unsigned 32 bit
integer generated by the Session-Sender. It MUST specify the number
of padding octets that the Session-Reflector will append to the
TWAMP-Test packet to be reflected. The Desired Reverse Padding Length
includes the Value-added octets. If P bit is set to 0, the Session-
Sender shall set all the bits in the Desired Reverse Padding Length
field to zero.
The values of the above fields are usually provided by a measurement
method, tool or algorithm. This measurement algorithm is outside the
scope of this specification.
5.2 Reflector behavior
The TWAMP Session-Reflector follows the procedures and guidelines in
Section 4.2 of [RFC5357], with some changes and additional functions.
When the Value-Added Octets Version 1 is selected, the behavior of
the Session-Reflector SHALL be as follows:
o The Session-Reflector MUST read the Version field. If Ver = 1,
the Session-Reflector MUST read the L, I and P flag bits.
o If L=1 and I=1, the Session-Reflector MUST read and extract the
information from the Last Seqno in Train field and the Desired
Reverse Packet Interval field in the value-added padding
octets.
- The Last Seqno in Train field MUST be compared to Sequence
number in the same packet in order to determine when a
complete train has been collected. The Session-Reflector
SHOULD buffer the packets belonging to the current train (or
store the packet-level performance data). After the last
packet of the train has been received, the Session-Reflector
SHOULD transmit the packets belonging to a reverse train
with a waiting time (packet interval) for each packet
indicated in the Desired Reverse Packet Interval field. If
the Desired Reverse Packet Interval field is set to zero,
then the Session-Reflector SHOULD transmit the packets as
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quickly as possible. The last packet within a train has
Sender Sequence Number = Last Seqno in Train.
- The Last Seqno in Train of a packet MUST also be compared to
the Last Seqno in Train of the previous packet in order to
determine if a new train needs to be collected. In case of
packet loss, the Session-Reflector MUST transmit the
incomplete train when it receives a packet with a Last SeqNo
in Train belonging to the another train (e.g. next train) of
the test session, or after a timeout. The timeout MAY be the
REFWAIT timer specified in section 4.2 of [RFC5357].
- Packets arriving out-of-order within a train MUST be
buffered at the Session-Reflector if the train is not yet
transmitted to the Session-Sender. If the train is already
transmitted, the test packet SHOULD be returned to the
Session-Sender as quickly as possible. The Session-Reflector
MUST not reorder the test packets if they happen to arrive
out-of-sequence.
- Duplicate packets within a train MUST be buffered at the
Session-Reflector if the train is not yet transmitted to the
Session-Sender. If the train is already transmitted, the
duplicate test packet SHOULD be returned to the Session-
Sender as quickly as possible. The Session-Reflector MUST
not discard duplicate test packets.
o If P=1, the Session-Reflector MUST read and extract the
information from the Desired Reverse Padding Length field in
the value-added padding octets.
- The Session-Reflector SHOULD transmit the packet with the
Desired Reverse Padding Length. If Symmetrical-Size mode is
used the Desired Reverse Padding Length must be ignored by
the Session-Reflector. The actual reflected packet size MUST
be large enough to contain all data required to be reflected
according to selected modes. If the Desired Reverse Padding
Length is larger than the Session-Reflector MTU, the MTU
MUST be used.
The Session-Reflector MUST implement the changes described above when
the Value-Added Octets Version 1 mode is selected.
5.2.1 Session-Reflector Packet Format
The Session-Reflector packet format follows the same procedure and
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guidelines as defined in TWAMP [RFC5357] and TWAMP Reflect Octets and
Symmetrical Size Features [RFC6038], with the following changes:
o The Session-Reflector MUST re-use (reflect) the value-added
padding octets (14 octets) provided in the Sender's Packet
Padding.
o The Session-Reflector MAY re-use the rest of the padding octets
in the Sender's Packet Padding.
The truncation process [RFC5357] is recommended when the Desired
Reverse Padding Length (P) bit is 0 and the Symmetrical mode is not
used. The Session-Reflector MUST truncate exactly 27 octets of
padding in Unauthenticated mode,and exactly 56 octets in
Authenticated and Encrypted modes.
5.3 Additional Considerations
Capacity measurements introduce an additional consideration when the
test sessions operate in TWAMP Light. When the Session-Reflector does
not have knowledge of the session state, the measurement system will
only be capable to estimate or calculate the capacity metrics in the
forward path direction of transmission. Capacity measurements in the
reverse path direction requires the Session-Reflector to have
knowledge of the session state and be capable to identify the test
packets belonging to a specific test session. The method for creating
a session state from the initial test packets on the TWAMP Light
Session-Reflector is outside the scope of this specification.
6 Security Considerations
The value-added padding octets permit DoS attacks on the responder
host communicating with core TWAMP [RFC5357]. The responder host MUST
provide a mechanism to protect or limit the use of its local memory,
buffer space or maximum transmission time for a train.
The security considerations that apply to any active measurement of
live networks are relevant here as well. See [RFC4656] and [RFC5357].
7 IANA Considerations
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IANA has created a TWAMP-Modes registry (as requested in [RFC5618]).
TWAMP-Modes are specified in TWAMP Server Greeting messages and Setup
Response messages, as described in Section 3.1 of [RFC5357],
consistent with Section 3.1 of [RFC4656]. Modes are indicated by
setting bits in the 32-bit Modes field that correspond to values in
the Modes registry. For the TWAMP-Modes registry, new features are
usually assigned increasing registry values that correspond to single
bit positions.
This memo does not define a new TWAMP mode. Therefore it is not a
recognized extension mechanism for TWAMP. A new mode is required to
communicate feature capability and use in an interoperable manner.
This is outside the scope of this memo.
8 References
8.1 Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4656] Shalunov, S., Teitelbaum, B., Karp, A., Boote, J., and M.
Zekauskas, "A One-way Active Measurement
Protocol(OWAMP)", RFC 4656, September 2006.
[RFC5136] Chimento, P. and Ishac,J., "Defining Network Capacity",
RFC 5136, February 2008.
[RFC5357] Hedayat, K., Krzanowski, R., Morton, A., Yum, K., and J.
Babiarz, "A Two-Way Active Measurement Protocol (TWAMP)",
RFC 5357, October 2008.
[RFC6038] Morton, A., Ciavattone, L., TWAMP Reflect Octets and
Symmetrical Size Features, RFC6038 , October 2010.
8.2 Informative References
[RRBNC] Ribeiro, V., Riedi, R., Baraniuk, R., Navratil, J.,
Cottrel, L., Pathchirp: Efficient available bandwidth
estimation for network paths, Passive and Active
Measurement Workshop, 2003.
[PDM] Dovrolis, C., Ramanathan, P., and Moore D., Packet
Dispersion Techniques and a Capacity Estimation
Methodology, IEEE/ACM Transactions on Networking,
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December 2004.
[ENHJMMB] Ekelin, S., Nilsson, M., Hartikainen, E., Johnsson, A.,
Mangs, J., Melander, B., Bjorkman, M., Real-time
measurement of end-to-end available bandwidth using
kalman filtering, Proceedings to the IEEE IFIP Network
Operations and Management Symposium, 2006.
[SBW] Sommers, J., Barford, P., Willinger, W., Laboratory-based
calibration of available bandwidth estimation tools,
Microprocess Microsyst., 2007.
[Y1540] ITU-T Y.1540, Internet protocol data communication service
- IP packet transfer and availability performance
parameters, 2011.
[MRM] Morton, A., Ramachandran, G., Maguluri, G., Reporting
Metrics Different Points of View, draft-ietf-ippm-
reporting-metrics-03, June 2010.
Author's Addresses
Steve Baillargeon
Ericsson
3500 Carling Avenue
Ottawa, Ontario K2H 8E9
Canada
EMail: steve.baillargeon@ericsson.com
Christofer Flinta
Ericsson
Farogatan 6
Stockholm, 164 80
Sweden
EMail: christofer.flinta@ericsson.com
Andreas Johnsson
Ericsson
Farogatan 6
Stockholm, 164 80
Sweden
EMail: andreas.a.johnsson@ericsson.com
Svante Ekelin
Baillargeon, et al. Expires March 11, 2012 [Page 16]
INTERNET DRAFT Value-Added TWAMP Octets September 8, 2011
Ericsson
Farogatan 6
Stockholm, 164 80
Sweden
EMail: svante.ekelin@ericsson.com
Baillargeon, et al. Expires March 11, 2012 [Page 17]
