Network Working Group S. Giacalone
Internet Draft Thomson Reuters
Intended status: Proposed Standard
Expires: December 2013 D. Ward
Cisco Systems
J. Drake
Juniper Networks
A. Atlas
Juniper Networks
S. Previdi
Cisco Systems
June 3, 2013
OSPF Traffic Engineering (TE) Metric Extensions
draft-ietf-ospf-te-metric-extensions-04.txt
Abstract
In certain networks, such as, but not limited to, financial
information networks (e.g. stock market data providers), network
performance criteria (e.g. latency) are becoming as critical to data
path selection as other metrics.
This document describes extensions to OSPF TE [RFC3630] such that
network performance information can be distributed and collected in a
scalable fashion. The information distributed using OSPF TE Metric
Extensions can then be used to make path selection decisions based on
network performance.
Note that this document only covers the mechanisms with which network
performance information is distributed. The mechanisms for measuring
network performance or acting on that information, once distributed,
are outside the scope of this document.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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Table of Contents
1. Introduction...................................................4
2. Conventions used in this document..............................5
3. TE Metric Extensions to OSPF TE................................5
4. Sub TLV Details................................................7
4.1. Unidirectional Link Delay Sub-TLV.........................7
4.1.1. Type.................................................7
4.1.2. Length...............................................7
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4.1.3. A bit................................................7
4.1.4. Reserved.............................................7
4.1.5. Delay Value..........................................7
4.2. Min/Max Unidirectional Link Delay Sub-TLV.................8
4.2.1. Type.................................................8
4.2.2. Length...............................................8
4.2.3. A bit................................................8
4.2.4. Reserved.............................................8
4.2.5. Low Delay............................................9
4.2.6. High Delay...........................................9
4.2.7. Reserved.............................................9
4.3. Unidirectional Delay Variation Sub-TLV....................9
4.3.1. Type................................................10
4.3.2. Length..............................................10
4.3.3. Reserved............................................10
4.3.4. Delay Variation.....................................10
4.4. Unidirectional Link Loss Sub-TLV.........................10
4.4.1. Type................................................11
4.4.2. Length..............................................11
4.4.3. A bit...............................................11
4.4.4. Reserved............................................11
4.4.5. Link Loss...........................................11
4.5. Unidirectional Residual Bandwidth Sub-TLV................11
4.5.1. Type................................................12
4.5.2. Length..............................................12
4.5.3. Residual Bandwidth..................................12
4.5. Unidirectional Available Bandwidth Sub-TLV...............13
4.5.4. Type................................................13
4.5.5. Length..............................................13
4.5.6. Available Bandwidth.................................13
5. Announcement Thresholds and Filters...........................13
6. Announcement Suppression......................................14
7. Network Stability and Announcement Periodicity................15
8. Enabling and Disabling Sub-TLVs...............................15
9. Static Metric Override........................................15
10. Compatibility................................................16
11. Security Considerations......................................16
12. IANA Considerations..........................................16
13. References...................................................16
13.1. Normative References....................................16
13.2. Informative References..................................16
14. Acknowledgments..............................................17
15. Author's Addresses...........................................17
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1. Introduction
In certain networks, such as, but not limited to, financial
information networks (e.g. stock market data providers), network
performance information (e.g. latency) is becoming as critical to
data path selection as other metrics.
In these networks, extremely large amounts of money rest on the
ability to access market data in "real time" and to predictably make
trades faster than the competition. Because of this, using metrics
such as hop count or cost as routing metrics is becoming only
tangentially important. Rather, it would be beneficial to be able to
make path selection decisions based on performance data (such as
latency) in a cost-effective and scalable way.
This document describes extensions to OSPF TE (hereafter called "OSPF
TE Metric Extensions"), that can be used to distribute network
performance information (such as link delay, delay variation, packet
loss, residual bandwidth, and available bandwidth).
The data distributed by OSPF TE Metric Extensions is meant to be used
as part of the operation of the routing protocol (e.g. by replacing
cost with latency or considering bandwidth as well as cost), by
enhancing CSPF, or for other uses such as supplementing the data used
by an Alto server [Alto]. With respect to CSPF, the data distributed
by OSPF TE Metric Extensions can be used to setup, fail over, and
fail back data paths using protocols such as RSVP-TE [RFC3209].
Note that the mechanisms described in this document only disseminate
performance information. The methods for initially gathering that
performance information, such as [RFC6375], or acting on it once it
is distributed are outside the scope of this document. Example
mechanisms to measure latency, delay variation, and loss in an MPLS
network are given in [RFC6374]. While this document does not
specify how the performance information should be obtained, the
measurement of delay SHOULD NOT vary significantly based upon the
offered traffic load. Thus, queuing delays and/or loss SHOULD NOT
be included in any dynamic delay measurement. For links, such as
Forwarding Adjacencies, care must be taken that measurement of the
associated delay avoids significant queuing delay; that could be
accomplished in a variety of ways, including either by measuring
with a traffic class that experiences minimal queuing or by summing
the measured link delays of the components of the link's path.
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2. Conventions used in this document
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].
In this document, these words will appear with that interpretation
only when in ALL CAPS. Lower case uses of these words are not to be
interpreted as carrying RFC-2119 significance.
3. TE Metric Extensions to OSPF TE
This document proposes new OSPF TE sub-TLVs that can be announced in
OSPF TE LSAs to distribute network performance information. The
extensions in this document build on the ones provided in OSPF TE
[RFC3630] and GMPLS [RFC4203].
OSPF TE LSAs [RFC3630] are opaque LSAs [RFC5250] with area flooding
scope. Each TLV has one or more nested sub-TLVs which permit the TE
LSA to be readily extended. There are two main types of OSPF TE LSA;
the Router Address or Link TE LSA. Like the extensions in GMPLS
(RFC4203), this document proposes several additional sub-TLVs for
the Link TE LSA:
Type Length Value
TBD1 4 Unidirectional Link Delay
TBD2 8 Low/High Unidirectional Link Delay
TBD3 4 Unidirectional Delay Variation
TBD4 4 Unidirectional Packet Loss
TBD5 4 Unidirectional Residual Bandwidth
TBD6 4 Unidirectional Available Bandwidth
As can be seen in the list above, the sub-TLVs described in this
document carry different types of network performance information.
Many (but not all) of the sub-TLVs include a bit called the Anomalous
(or "A") bit. When the A bit is clear (or when the sub-TLV does not
include an A bit), the sub-TLV describes steady state link
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performance. This information could conceivably be used to construct
a steady state performance topology for initial tunnel path
computation, or to verify alternative failover paths.
When network performance violates configurable link-local thresholds
a sub-TLV with the A bit set is advertised. These sub-TLVs could be
used by the receiving node to determine whether to fail traffic to a
backup path, or whether to calculate an entirely new path. From an
MPLS perspective, the intent of the A bit is to permit LSP ingress
nodes to:
A) Determine whether the link referenced in the sub-TLV affects any
of the LSPs for which it is ingress. If there are, then:
B) The node determines whether those LSPs still meet end-to-end
performance objectives. If not, then:
C) The node could then conceivably move affected traffic to a pre-
established protection LSP or establish a new LSP and place the
traffic in it.
If link performance then improves beyond a configurable minimum
value (reuse threshold), that sub-TLV can be re-advertised with the
Anomalous bit cleared. In this case, a receiving node can
conceivably do whatever re-optimization (or failback) it wishes to
do (including nothing).
Note that when a sub-TLV does not include the A bit, that sub-TLV
cannot be used for failover purposes. The A bit was intentionally
omitted from some sub-TLVs to help mitigate oscillations. See section
7. 1. for more information.
Consistent with existing OSPF TE specifications (RFC3630), the
bandwidth advertisements defined in this draft MUST be encoded as
IEEE floating point values. The delay and delay variation
advertisements defined in this draft MUST be encoded as integer
values. Delay values MUST be quantified in units of microseconds,
packet loss MUST be quantified as a percentage of packets sent, and
bandwidth MUST be sent as bytes per second. All values (except
residual bandwidth) MUST be calculated as rolling averages where the
averaging period MUST be a configurable period of time. See section
5. for more information.
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4. Sub TLV Details
4.1. Unidirectional Link Delay Sub-TLV
This sub-TLV advertises the average link delay between two directly
connected OSPF neighbors. The delay advertised by this sub-TLV MUST
be the delay from the local neighbor to the remote one (i.e. the
forward path latency). The format of this sub-TLV is shown in the
following diagram:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TBD1 | 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|A| RESERVED | Delay |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.1.1. Type
This sub-TLV has a type of TBD1.
4.1.2. Length
The length is 4.
4.1.3. A bit
This field represents the Anomalous (A) bit. The A bit is set when
the measured value of this parameter exceeds its configured maximum
threshold. The A bit is cleared when the measured value falls below
its configured reuse threshold. If the A bit is clear, the sub-TLV
represents steady state link performance.
4.1.4. Reserved
This field is reserved for future use. It MUST be set to 0 when sent
and MUST be ignored when received.
4.1.5. Delay Value
This 24-bit field carries the average link delay over a configurable
interval in micro-seconds, encoded as an integer value. When set to
the maximum value 16,777,215 (16.777215 sec), then the delay is at
least that value and may be larger. If there is no value to send
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(unmeasured and not statically specified), then the sub-TLV should
not be sent or be withdrawn.
4.2. Min/Max Unidirectional Link Delay Sub-TLV
This sub-TLV advertises the minimum and maximum delay values between
two directly connected OSPF neighbors. The delay advertised by this
sub-TLV MUST be the delay from the local neighbor to the remote one
(i.e. the forward path latency). The format of this sub-TLV is shown
in the following diagram:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TBD2 | 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|A| RESERVED | Min Delay |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED | Max Delay |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.2.1. Type
This sub-TLV has a type of TBD2.
4.2.2. Length
The length is 8.
4.2.3. A bit
This field represents the Anomalous (A) bit. The A bit is set when
one or more measured values exceed a configured maximum threshold.
The A bit is cleared when the measured value falls below its
configured reuse threshold. If the A bit is clear, the sub-TLV
represents steady state link performance.
4.2.4. Reserved
This field is reserved for future use. It MUST be set to 0 when sent
and MUST be ignored when received.
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4.2.5. Low Delay
This 24-bit field carries minimum measured link delay value (in
microseconds) over a configurable interval, encoded as an integer
value.
Implementations MAY also permit the configuration of a static (non
dynamic) offset value (in microseconds) to be added to the measured
delay value, to facilitate the communication of operator specific
delay constraints.
When set to the maximum value 16,777,215 (16.777215 sec), then the
delay is at least that value and may be larger.
4.2.6. High Delay
This 24-bit field carries the maximum measured link delay value (in
microseconds) over a configurable interval, encoded as an integer
value.
Implementations MAY also permit the configuration of a static (non
dynamic) offset value (in microseconds) to be added to the measured
delay value, to facilitate the communication of operator specific
delay constraints.
It is possible for the high delay and low delay to be the same value.
When the delay value is set to maximum value 16,777,215 (16.777215
sec), then the delay is at least that value and may be larger.
4.2.7. Reserved
This field is reserved for future use. It MUST be set to 0 when sent
and MUST be ignored when received.
When only an average delay value is sent, this field is not present
in the TLV.
4.3. Unidirectional Delay Variation Sub-TLV
This sub-TLV advertises the average link delay variation between two
directly connected OSPF neighbors. The delay variation advertised by
this sub-TLV MUST be the delay from the local neighbor to the remote
one (i.e. the forward path latency). The format of this sub-TLV is
shown in the following diagram:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TBD3 | 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED | Delay Variation |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.3.1. Type
This sub-TLV has a type of TBD3.
4.3.2. Length
The length is 4.
4.3.3. Reserved
This field is reserved for future use. It MUST be set to 0 when sent
and MUST be ignored when received.
4.3.4. Delay Variation
This 24-bit field carries the average link delay variation over a
configurable interval in micro-seconds, encoded as an integer value.
When set to 0, it has not been measured. When set to the maximum
value 16,777,215 (16.777215 sec), then the delay is at least that
value and may be larger.
4.4. Unidirectional Link Loss Sub-TLV
This sub-TLV advertises the loss (as a packet percentage) between two
directly connected OSPF neighbors. The link loss advertised by this
sub-TLV MUST be the packet loss from the local neighbor to the remote
one (i.e. the forward path loss). The format of this sub-TLV is shown
in the following diagram:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TBD4 | 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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|A| RESERVED | Link Loss |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.4.1. Type
This sub-TLV has a type of TBD4
4.4.2. Length
The length is 4.
4.4.3. A bit
This field represents the Anomalous (A) bit. The A bit is set when
the measured value of this parameter exceeds its configured maximum
threshold. The A bit is cleared when the measured value falls below
its configured reuse threshold. If the A bit is clear, the sub-TLV
represents steady state link performance.
4.4.4. Reserved
This field is reserved for future use. It MUST be set to 0 when sent
and MUST be ignored when received.
4.4.5. Link Loss
This 24-bit field carries link packet loss as a percentage of the
total traffic sent over a configurable interval. The basic unit is
0.000003%, where (2^24 - 2) is 50.331642%. This value is the highest
packet loss percentage that can be expressed (the assumption being
that precision is more important on high speed links than the ability
to advertise loss rates greater than this, and that high speed links
with over 50% loss are unusable). Therefore, measured values that are
larger than the field maximum SHOULD be encoded as the maximum value.
When set to a value of all 1s (2^24 - 1), the link packet loss has
not been measured.
4.5. Unidirectional Residual Bandwidth Sub-TLV
This TLV advertises the residual bandwidth (defined in section 4.5.3.
between two directly connected OSPF neighbors. The residual bandwidth
advertised by this sub-TLV MUST be the residual bandwidth from the
system originating the LSA to its neighbor.
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The format of this sub-TLV is shown in the following diagram:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TBD5 | 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Residual Bandwidth |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.5.1. Type
This sub-TLV has a type of TBD5.
4.5.2. Length
The length is 4.
4.5.3. Residual Bandwidth
This field carries the residual bandwidth on a link, forwarding
adjacency [RFC4206], or bundled link in IEEE floating point format
with units of bytes per second. For a link or forwarding adjacency,
residual bandwidth is defined to be Maximum Bandwidth [RFC3630] minus
the bandwidth currently allocated to RSVP-TE LSPs. For a bundled
link, residual bandwidth is defined to be the sum of the component
link residual bandwidths.
The calculation of Residual Bandwidth is different than that of
Unreserved Bandwidth [RFC3630]. Residual Bandwidth subtracts tunnel
reservations from Maximum Bandwidth (i.e. the link capacity)
[RFC3630] and provides an aggregated remainder across QoS classes.
Unreserved Bandwidth [RFC3630], on the other hand, is subtracted from
the Maximum Reservable Bandwidth (the bandwidth that can
theoretically be reserved) [RFC3630] and provides per-QoS-class
remainders. Residual Bandwidth and Unreserved Bandwidth [RFC3630] can
be used concurrently, and each has a separate use case (e.g. the
former can be used for applications like Weighted ECMP while the
latter can be used for call admission control).
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4.5. Unidirectional Available Bandwidth Sub-TLV
This TLV advertises the available bandwidth (defined in section
4.5.6. ) between two directly connected OSPF neighbors. The available
bandwidth advertised by this sub-TLV MUST be the available bandwidth
from the system originating the LSA to its neighbor. The format of
this sub-TLV is shown in the following diagram:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TBD6 | 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Available Bandwidth |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.5.4. Type
This sub-TLV has a type of TBD6.
4.5.5. Length
The length is 4.
4.5.6. Available Bandwidth
This field carries the available bandwidth on a link, forwarding
adjacency, or bundled link in IEEE floating point format with units
of bytes per second. For a link or forwarding adjacency, available
bandwidth is defined to be residual bandwidth (see section 4.5. )
minus the measured bandwidth used for the actual forwarding of non-
RSVP-TE LSP packets. For a bundled link, available bandwidth is
defined to be the sum of the component link available bandwidths.
5. Announcement Thresholds and Filters
The values advertised in all sub-TLVs (except min/max delay and
residual bandwidth) MUST represent an average over a period or be
obtained by a filter that is reasonably representative of an
average. For example, a rolling average is one such filter.
Low or high delay MAY be the lowest and/or highest measured value
over a measurement interval or MAY make use of a filter, or other
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technique to obtain a reasonable representation of a low and high
value representative of the interval with compensation for outliers.
The measurement interval, any filter coefficients, and any
advertisement intervals MUST be configurable per sub-TLV.
In addition to the measurement intervals governing re-advertisement,
implementations SHOULD provide per sub-TLV configurable accelerated
advertisement thresholds, such that:
1. If the measured parameter falls outside a configured upper bound
for all but the min delay metric (or lower bound for min-delay
metric only) and the advertised sub-TLV is not already outside
that bound or,
2. If the difference between the last advertised value and current
measured value exceed a configured threshold then,
3. The advertisement is made immediately.
4. For sub-TLVs which include an A-bit (except low/high delay), an
additional threshold SHOULD be included corresponding to the
threshold for which the performance is considered anomalous (and
sub-TLVs with the A bit are sent). The A-bit is cleared when the
sub-TLV's performance has been below (or re-crosses) this
threshold for an advertisement interval(s) to permit fail back.
To prevent oscillations, only the high threshold or the low threshold
(but not both) may be used to trigger any given sub-TLV that supports
both.
Additionally, once outside of the bounds of the threshold, any
readvertisement of a measurement within the bounds would remain
governed solely by the measurement interval for that sub-TLV.
6. Announcement Suppression
When link performance values change by small amounts that fall under
thresholds that would cause the announcement of a sub-TLV,
implementations SHOULD suppress sub-TLV readvertisement and/or
lengthen the period within which they are refreshed.
Only the accelerated advertisement threshold mechanism described in
section 6 may shorten the re-advertisement interval.
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All suppression and re-advertisement interval backoff timer features
SHOULD be configurable.
7. Network Stability and Announcement Periodicity
Sections 6 and 7 provide configurable mechanisms to bound the number
of re-advertisements. Instability might occur in very large networks
if measurement intervals are set low enough to overwhelm the
processing of flooded information at some of the routers in the
topology. Therefore care SHOULD be taken in setting these values.
Additionally, the default measurement interval for all sub-TLVs
SHOULD be 30 seconds.
Announcements MUST also be able to be throttled using configurable
inter-update throttle timers. The minimum announcement periodicity is
1 announcement per second. The default value SHOULD be set to 120
seconds.
Implementations SHOULD NOT permit the inter-update timer to be lower
than the measurement interval.
Furthermore, it is RECOMMENDED that any underlying performance
measurement mechanisms not include any significant buffer delay, any
significant buffer induced delay variation, or any significant
loss due to buffer overflow or due to active queue management.
8. Enabling and Disabling Sub-TLVs
Implementations MUST make it possible to individually enable or
disable each sub-TLV based on configuration.
9. Static Metric Override
Implementations SHOULD permit the static configuration and/or manual
override of dynamic measurements data on a per sub-TLV, per metric
basis in order to simplify migrations and to mitigate scenarios where
measurements are not possible across an entire network.
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10. Compatibility
As per (RFC3630), unrecognized TLVs should be silently ignored
11. Security Considerations
This document does not introduce security issues beyond those
discussed in [RFC3630] and [RFC5329].
12. IANA Considerations
IANA maintains the registry for the sub-TLVs. OSPF TE Metric
Extensions will require one new type code per sub-TLV defined in this
document.
13. References
13.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3630] Katz, D., Kompella, K., Yeung, D., "Traffic
Engineering (TE) Extensions to OSPF Version 2", RFC 3630,
September 2003.
[RFC6374] Frost, D. and S. Bryant, "Packet Loss and Delay
Measurement for MPLS Networks", RFC 6374, September 2011.
13.2. Informative References
[RFC2328] Moy, J, "OSPF Version 2", RFC 2328, April 1998
[RFC3031] Rosen, E., Viswanathan, A., Callon, R., "Multiprotocol
Label Switching Architecture", January 2001
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[RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan,
V., and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
Tunnels", RFC 3209, December 2001.
[RFC5250] Berger, L., Bryskin I., Zinin, A., Coltun, R., "The OSPF
Opaque LSA Option", RFC 5250, July 2008.
[RFC6375] Frost, D. and S. Bryant, "A Packet Loss and Delay
Measurement Profile for MPLS-Based Transport Networks",
RFC 6375, September 2011.
[Alto] R. Alimi R. Penno Y. Yang, "ALTO Protocol"
14. Acknowledgments
The authors would like to recognize Ayman Soliman, Nabil Bitar, David
McDysan, Edward Crabbe, and Don Fedyk for their contributions.
The authors also recognize Curtis Villamizar for significant comments
and direct content collaboration.
This document was prepared using 2-Word-v2.0.template.dot.
15. Author's Addresses
Spencer Giacalone
Thomson Reuters
195 Broadway
New York, NY 10007, USA
Email: Spencer.giacalone@thomsonreuters.com
Dave Ward
Cisco Systems
170 West Tasman Dr.
San Jose, CA 95134, USA
Email: dward@cisco.com
Giacalone, et al Expires December 3, 2013 [Page 17]
Internet-Draft OSPF TE Metric Extensions June 2013
John Drake
Juniper Networks
1194 N. Mathilda Ave.
Sunnyvale, CA 94089, USA
Email: jdrake@juniper.net
Alia Atlas
Juniper Networks
1194 N. Mathilda Ave.
Sunnyvale, CA 94089, USA
Email: akatlas@juniper.net
Stefano Previdi
Cisco Systems
Via Del Serafico 200
00142 Rome
Italy
Email: sprevidi@cisco.com
Giacalone, et al Expires December 3, 2013 [Page 18]
