draft-ietf-alto-performance-metrics-01.txt   draft-ietf-alto-performance-metrics-02.txt 
ALTO Working Group Q. Wu ALTO Working Group Q. Wu
Internet-Draft Huawei Internet-Draft Huawei
Intended status: Standards Track Y. Yang Intended status: Standards Track Y. Yang
Expires: September 4, 2017 Yale University Expires: January 3, 2018 Yale University
Y. Lee Y. Lee
D. Dhody D. Dhody
Huawei Huawei
S. Randriamasy S. Randriamasy
Nokia Bell Labs Nokia Bell Labs
March 3, 2017 July 2, 2017
ALTO Performance Cost Metrics ALTO Performance Cost Metrics
draft-ietf-alto-performance-metrics-01 draft-ietf-alto-performance-metrics-02
Abstract Abstract
Cost Metric is a basic concept in Application-Layer Traffic Cost Metric is a basic concept in Application-Layer Traffic
Optimization (ALTO). It is used in both the Cost Map Service and the Optimization (ALTO). It is used in both the Cost Map Service and the
Endpoint Cost Service. Endpoint Cost Service.
Different applications may benefit from different Cost Metrics. For Different applications may benefit from different Cost Metrics. For
example, a Resource Consumer may prefer Resource Providers that example, a Resource Consumer may prefer Resource Providers that offer
offers a low delay delivery to the Resource Consumer. However the a low delay delivery to the Resource Consumer. However the base ALTO
base ALTO protocol [ALTO] has documented only one single cost metric, protocol [ALTO] has documented only one single cost metric, i.e., the
i.e., the generic "routingcost" metric (Sec. 14.2 of ALTO base generic "routingcost" metric (Sec. 14.2 of ALTO base specification
specification [ALTO]). [ALTO]).
This document, proposes a set of Cost Metrics, derived and aggregated This document, proposes a set of Cost Metrics, derived and aggregated
from routing protocols with different granularity and scope, such as from routing protocols with different granularity and scope, such as
BGP-LS,OSPF-TE and ISIS-TE, or from end to end traffic management BGP-LS,OSPF-TE and ISIS-TE, or from end-to-end traffic management
tools. It currently documents Network Performance Cost Metrics tools. It currently documents Network Performance Cost Metrics
reporting on network delay, jitter, packet loss, hop count, and reporting on network delay, jitter, packet loss, hop count, and
bandwidth. These metrics may be exposed by an ALTO Server to allow bandwidth. These metrics may be exposed by an ALTO Server to allow
applications to determine "where" to connect based on network applications to determine "where" to connect based on network
performance criteria. Additional Cost Metrics involving ISP specific performance criteria. Additional Cost Metrics involving ISP specific
considerations or other network technologies may be documented in considerations or other network technologies may be documented in
further versions of this draft. further versions of this draft.
Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", Requirements Language The key words "MUST", "MUST NOT", "REQUIRED",
"SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY",
skipping to change at page 2, line 20 skipping to change at page 2, line 20
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 4, 2017. This Internet-Draft will expire on January 3, 2018.
Copyright Notice Copyright Notice
Copyright (c) 2017 IETF Trust and the persons identified as the Copyright (c) 2017 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Challenges on data sources and computation of ALTO 2. Challenges on data sources and computation of ALTO
performance metrics . . . . . . . . . . . . . . . . . . . . . 5 performance metrics . . . . . . . . . . . . . . . . . . . . . 5
2.1. Data sources . . . . . . . . . . . . . . . . . . . . . . 5 2.1. Data sources . . . . . . . . . . . . . . . . . . . . . . 5
2.2. Computation of ALTO performance metrics . . . . . . . . . 5 2.2. Computation of ALTO performance metrics . . . . . . . . . 5
3. Cost Metric: POWDelay . . . . . . . . . . . . . . . . . . . . 6 3. Cost Metric: POWDelay . . . . . . . . . . . . . . . . . . . . 6
4. Cost Metric: RTT . . . . . . . . . . . . . . . . . . . . . . 8 4. Cost Metric: RTT . . . . . . . . . . . . . . . . . . . . . . 8
5. Cost Metric: PDV . . . . . . . . . . . . . . . . . . . . . . 9 5. Cost Metric: PDV . . . . . . . . . . . . . . . . . . . . . . 10
6. Cost Metric: Hop Count . . . . . . . . . . . . . . . . . . . 11 6. Cost Metric: Hop Count . . . . . . . . . . . . . . . . . . . 12
7. Cost Metric: Packet Loss . . . . . . . . . . . . . . . . . . 13 7. Cost Metric: Packet Loss . . . . . . . . . . . . . . . . . . 14
8. Traffic Engineering Performance Cost Metrics . . . . . . . . 15 8. Traffic Engineering Performance Cost Metrics . . . . . . . . 16
8.1. Cost Metric: Link Maximum Reservable Bandwidth . . . . . 16 8.1. Cost Metric: Link Maximum Reservable Bandwidth . . . . . 17
8.2. Cost Metric: Link Residue Bandwidth . . . . . . . . . . . 17 8.2. Cost Metric: Link Residue Bandwidth . . . . . . . . . . . 18
8.3. Cost Metric: Link Available Bandwidth . . . . . . . . . . 19 8.3. Cost Metric: Link Available Bandwidth . . . . . . . . . . 20
8.4. Cost Metric: Link Utilized Bandwidth . . . . . . . . . . 21 8.4. Cost Metric: Link Utilized Bandwidth . . . . . . . . . . 22
9. Security Considerations . . . . . . . . . . . . . . . . . . . 23 9. Security Considerations . . . . . . . . . . . . . . . . . . . 24
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 24 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 24 11. References . . . . . . . . . . . . . . . . . . . . . . . . . 25
11.1. Normative References . . . . . . . . . . . . . . . . . . 24 11.1. Normative References . . . . . . . . . . . . . . . . . . 25
11.2. Informative References . . . . . . . . . . . . . . . . . 26 11.2. Informative References . . . . . . . . . . . . . . . . . 27
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 26 Appendix A. Open Issue List . . . . . . . . . . . . . . . . . . 27
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 27
1. Introduction 1. Introduction
Cost Metric is a basic concept in Application-Layer Traffic Cost Metric is a basic concept in Application-Layer Traffic
Optimization (ALTO). It is used in both the Cost Map Service and the Optimization (ALTO). It is used in both the Cost Map Service and the
Endpoint Cost Service. In particular, applications may benefit from Endpoint Cost Service. In particular, applications may benefit from
knowing network performance measured on several Cost Metrics. For knowing network performance measured on several Cost Metrics. For
example, a more delay sensitive application may focus on latency, and example, a more delay-sensitive application may focus on latency, and
a more bandwidth-sensitive application may focus on available a more bandwidth-sensitive application may focus on available
bandwidth. bandwidth.
This document introduces a set new cost metrics, listed in Table 1, This document introduces a set of new cost metrics, listed in
to support the aforementioned applications and allow them to Table 1, to support the aforementioned applications and allow them to
determine "where" to connect based on network performance criteria. determine "where" to connect based on network performance criteria.
Hence, this document extends the base ALTO protocol [ALTO], which Hence, this document extends the base ALTO protocol [ALTO], which
defines only a single cost metric, i.e., the generic "routingcost" defines only a single cost metric, i.e., the generic "routingcost"
metric (Sec. 14.2 of ALTO base specification [ALTO]). metric (Sec. 14.2 of ALTO base specification [ALTO]).
+----------+--------------+---------------------------------------------+ +----------+--------------+---------------------------------------------+
|Namespace | Property | Reference | |Namespace | Property | Reference |
+----------+--------------+---------------------------------------------+ +----------+--------------+---------------------------------------------+
| | owdelay | See Section 3,[RFC2679] Section 3.6 | | | owdelay | See Section 3,[RFC2679] Section 3.6 |
| | rtt | See Section 4,[RFC2681] Section 2.6 | | | rtt | See Section 4,[RFC2681] Section 2.6 |
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| | residbw | See Section 8.2,[RFC7810] Section 4.5 | | | residbw | See Section 8.2,[RFC7810] Section 4.5 |
| | availbw | See Section 8.3,[RFC7810] Section 4.6 | | | availbw | See Section 8.3,[RFC7810] Section 4.6 |
| | utilbw | See Section 8.4,[RFC7810 Section 4.7 | | | utilbw | See Section 8.4,[RFC7810 Section 4.7 |
+----------+--------------+---------------------------------------------+ +----------+--------------+---------------------------------------------+
Table 1. Table 1.
The purpose of this draft is to list the metrics likely to be exposed The purpose of this draft is to list the metrics likely to be exposed
to ALTO Clients, including those already specified in other to ALTO Clients, including those already specified in other
standardization groups and as such it does not claim novelty on all standardization groups and as such it does not claim novelty on all
the specified metrics. Some metrics may have values produced by the specified metrics. Some metrics may have values produced by
explicitely specified measurement methods such as those specified in explicitly specified measurement methods such as those specified in
IPPM, some may be ISP dependent such as those registered in ISIS or IPPM, some may be ISP dependent such as those registered in ISIS or
OSPF-TE. In this case, this document will refer to the relevant OSPF-TE. In this case, this document will refer to the relevant
specifications. specifications.
An ALTO server may provide a subset of the cost metrics described in An ALTO server may provide a subset of the cost metrics described in
this document. These cost metrics can be retrieved and aggregated this document. These cost metrics can be retrieved and aggregated
from routing protocols or other traffic measurement management tools from routing protocols or other traffic measurement management tools
(See Figure 1). Note that these cost metrics are optional and not (See Figure 1). Note that these cost metrics are optional and not
all them need to be exposed to applications. If some are subject to all them need to be exposed to applications. If some are subject to
privacy concerns, the ALTO server should not provide them to the privacy concerns, the ALTO server should not provide them to the
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| ALTO |<----------------| Routing | | ALTO |<----------------| Routing |
| Server | and aggregation| | | Server | and aggregation| |
| |<-------------+ | Protocol| | |<-------------+ | Protocol|
+--------+ | +---------+ +--------+ | +---------+
| |
| +---------+ | +---------+
| |Management | |Management
---| | ---| |
| Tool | | Tool |
+---------+ +---------+
Figure 1.End to End Path Cost Metrics Exposing Figure 1.End-to-End Path Cost Metrics Exposing
When an ALTO server supports a cost metric defined in this document, When an ALTO server supports a cost metric defined in this document,
it SHOULD announce this metric in its IRD. it SHOULD announce this metric in its IRD.
Additionally, further versions of this document may define network Additionally, further versions of this document may define network
metric values that stem from both measurements and provider policy as metric values that stem from both measurements and provider policies
for example, many end to end path bandwidth related ALTO metrics. as for example, many end-to-end path bandwidth related ALTO metrics.
ALTO may convey such information, not available via 3rd party ALTO may convey such information, not available via 3rd party
measurement tools. Besides, IPPM informational RFC 5136 points the measurement tools. Besides, IPPM informational RFC 5136 points the
difficulty to have a unified nomenclature for network capacity difficulty to have a unified nomenclature for network capacity
related measurements. related measurements.
As for the reliability and trust in the exposed metric values, As for the reliability and trust in the exposed metric values,
applications will rapidly give up using ALTO-based guidance if they applications will rapidly give up using ALTO-based guidance if they
feel the exposed information does not preserve their performance feel the exposed information does not preserve their performance
level or even degrades it. level or even degrades it.
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the cost metrics defined in this document can be computed using the cost metrics defined in this document can be computed using
routing systems as the data sources. Mechanisms defined in routing systems as the data sources. Mechanisms defined in
[RFC3630], [RFC3784], [OSPF-TE], [ISIS-TE], [BGP-LS] and [BGP-PM] [RFC3630], [RFC3784], [OSPF-TE], [ISIS-TE], [BGP-LS] and [BGP-PM]
that allow an ALTO Server to retrieve and derive the necessary that allow an ALTO Server to retrieve and derive the necessary
information to compute the metrics that we describe in this document. information to compute the metrics that we describe in this document.
One challenge lies in the data sources originating the ALTO metric One challenge lies in the data sources originating the ALTO metric
values. The very purpose of ALTO is to guide application traffic values. The very purpose of ALTO is to guide application traffic
with provider network centric information that may be exposed to ALTO with provider network centric information that may be exposed to ALTO
Clients in the form of network performance metric values. Not all of Clients in the form of network performance metric values. Not all of
them metrics have values produced by standardized measurement methods these metrics have values produced by standardized measurement
or routing protocols. Some of them involve provider-centric policy methods or routing protocols. Some of them involve provider-centric
considerations. Some of them may describe wireless or cellular policy considerations. Some of them may describe wireless or
networks. To reliably guide users and applications while preserving cellular networks. To reliably guide users and applications while
provider privacy, ALTO performance metric values may also add preserving provider privacy, ALTO performance metric values may also
abstraction to measurements or provide unitless performance scores. add abstraction to measurements or provide unitless performance
scores.
2.2. Computation of ALTO performance metrics 2.2. Computation of ALTO performance metrics
The metric values exposed by an ALTO server may result from The metric values exposed by an ALTO server may result from
additional processing on measurements from data sources to compute additional processing on measurements from data sources to compute
exposed metrics. This may invlove data processing tasks such as exposed metrics. This may involve data processing tasks such as
aggregating the results across multiple systems, removing outliers, aggregating the results across multiple systems, removing outliers,
and creating additional statistics. and creating additional statistics.
One challenge in describing the metrics is that performance metrics One challenge in describing the metrics is that performance metrics
often depend on configuration parameters. For example, the value of often depend on configuration parameters. For example, the value of
packet loss rate depends on the measurement interval and varies over packet loss rate depends on the measurement interval and varies over
time. To handle this issue, an ALTO server may collect data on time time. To handle this issue, an ALTO server may collect data on time
periods covering the past and present or only collect data on present periods covering the previous and current time or only collect data
time. The ALTO server may further aggregate these data to provide an on present time. The ALTO server may further aggregate these data to
abstract and unified view that can be more useful to applications. provide an abstract and unified view that can be more useful to
To make the ALTO client better understand how to use these applications. To make the ALTO client better understand how to use
performance data, the ALTO server may provide the client with the these performance data, the ALTO server may provide the client with
validity period of the exposed metric values. the validity period of the exposed metric values.
Another challenge relates to the availability of end to end path Another challenge relates to the availability of end-to-end path
values for certain metrics. Applications value information relating values for certain metrics. Applications value information relating
to bandwidth availability where as bandwidth related metrics can to bandwidth availability where as bandwidth related metrics can
often be only measured at the link level. This document specifies a often be only measured at the link level. This document specifies a
set of link-level bandwidth related values that may be exposed as set of link-level bandwidth related values that may be exposed as
such by an ALTO server. The server may also expose other metrics such by an ALTO server. The server may also expose other metrics
derived from their aggregation and having different levels of derived from their aggregation and having different levels of
endpoint granularity, e.g. link endpoints or session endpoints. The endpoint granularity, e.g. link endpoints or session endpoints. The
metric specifications may also expose the utilised aggregation laws. metric specifications may also expose the utilised aggregation laws.
3. Cost Metric: POWDelay 3. Cost Metric: POWDelay
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To specify spatial and temporal maximum reservable bandwidth over To specify spatial and temporal maximum reservable bandwidth over
the specified source and destination. The value is corresponding the specified source and destination. The value is corresponding
to the maximum bandwidth that can be reserved (motivated from RFC to the maximum bandwidth that can be reserved (motivated from RFC
3630 Sec. 2.5.7.). The spatial aggregation unit is specified in 3630 Sec. 2.5.7.). The spatial aggregation unit is specified in
the query context (e.g., PID to PID, or endpoint to endpoint). the query context (e.g., PID to PID, or endpoint to endpoint).
Method of Measurement or Calculation: Method of Measurement or Calculation:
Maximum Reserveable Bandwidth is the bandwidth measured between Maximum Reserveable Bandwidth is the bandwidth measured between
two directly connected IS-IS neighbors or OSPF neighbor, See two directly connected IS-IS neighbors or OSPF neighbors, See
section 3.5 of [RFC5305] for Measurement Method. section 3.5 of [RFC5305] for Measurement Method.
Units of Measurement: Units of Measurement:
The unit of measurement is byte per seconds. The unit of measurement is byte per seconds.
Measurement Point(s) with Potential Measurement Domain: Measurement Point(s) with Potential Measurement Domain:
See section 2.1, Data sources. See section 2.1, Data sources.
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To specify spatial and temporal residual bandwidth over the To specify spatial and temporal residual bandwidth over the
specified source and destination. The value is calculated by specified source and destination. The value is calculated by
subtracting tunnel reservations from Maximum Bandwidth (motivated subtracting tunnel reservations from Maximum Bandwidth (motivated
from [RFC7810], Sec.4.5.). The spatial aggregation unit is from [RFC7810], Sec.4.5.). The spatial aggregation unit is
specified in the query context (e.g., PID to PID, or endpoint to specified in the query context (e.g., PID to PID, or endpoint to
endpoint). endpoint).
Method of Measurement or Calculation: Method of Measurement or Calculation:
Residue Bandwidth is the Unidirectional Residue bandwidth measured Residue Bandwidth is the Unidirectional Residue bandwidth measured
between two directly connected IS-IS neighbors or OSPF neighbor, between two directly connected IS-IS neighbors or OSPF neighbors,
See section 4.5 of [RFC7810] for Measurement Method. See section 4.5 of [RFC7810] for Measurement Method.
Units of Measurement: Units of Measurement:
The unit of measurement is byte per seconds. The unit of measurement is byte per seconds.
Measurement Point(s) with Potential Measurement Domain: Measurement Point(s) with Potential Measurement Domain:
See section 2.1, Data sources. See section 2.1, Data sources.
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specified source and destination. The value is calculated by specified source and destination. The value is calculated by
subtracting the measured bandwidth used for the actual forwarding subtracting the measured bandwidth used for the actual forwarding
of best effort traffic from Residue Bandwidth (motivated from of best effort traffic from Residue Bandwidth (motivated from
[RFC7810], Sec.4.6.). The spatial aggregation level is specified [RFC7810], Sec.4.6.). The spatial aggregation level is specified
in the query context (e.g., PID to PID, or endpoint to endpoint). in the query context (e.g., PID to PID, or endpoint to endpoint).
Method of Measurement or Calculation: Method of Measurement or Calculation:
Available bandwidth is the Unidirectional Available bandwidth Available bandwidth is the Unidirectional Available bandwidth
measured between two directly connected IS-IS neighbors or OSPF measured between two directly connected IS-IS neighbors or OSPF
neighbor, See section 4.6 of [RFC7810] for Measurement Method. neighbors, See section 4.6 of [RFC7810] for Measurement Method.
Units of Measurement: Units of Measurement:
The unit of measurement is byte per seconds. The unit of measurement is byte per seconds.
Measurement Point(s) with Potential Measurement Domain: Measurement Point(s) with Potential Measurement Domain:
See section 2.1, Data sources. See section 2.1, Data sources.
Measurement Timing: Measurement Timing:
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To specify spatial and temporal utilized bandwidth over the To specify spatial and temporal utilized bandwidth over the
specified source and destination. The value is corresponding to specified source and destination. The value is corresponding to
the actual measured bandwidth used for all traffic (motivated from the actual measured bandwidth used for all traffic (motivated from
[RFC7810], Sec.4.7.). The spatial aggregation level is specified [RFC7810], Sec.4.7.). The spatial aggregation level is specified
in the query context (e.g., PID to PID, or endpoint to endpoint). in the query context (e.g., PID to PID, or endpoint to endpoint).
Method of Measurement or Calculation: Method of Measurement or Calculation:
Link Utilizated bandwidth is Unidirectional utilization bandwidth Link Utilizated bandwidth is Unidirectional utilization bandwidth
measured between two directly connected IS-IS neighbors or OSPF measured between two directly connected IS-IS neighbors or OSPF
neighbor, See section 4.7 of [RFC7810] for Measurement Method. neighbors, See section 4.7 of [RFC7810] for Measurement Method.
Units of Measurement: Units of Measurement:
The unit of measurement is byte per seconds. The unit of measurement is byte per seconds.
Measurement Point(s) with Potential Measurement Domain: Measurement Point(s) with Potential Measurement Domain:
See section 2.1, Data sources. See section 2.1, Data sources.
Measurement Timing: Measurement Timing:
Link Utilized bandwidth is Unidirectional utilization bandwidth Link Utilized bandwidth is Unidirectional utilization bandwidth
measured between two directly connected IS-IS neighbors or OSPF measured between two directly connected IS-IS neighbors or OSPF
neighbor, See section 5 of [RFC7810] for Measurement Timing. neighbors, See section 5 of [RFC7810] for Measurement Timing.
Use and Applications: Use and Applications:
See section 3 for use and application. See section 3 for use and application.
Example 10: utilbw value on source-destination endpoint pairs Example 10: utilbw value on source-destination endpoint pairs
POST /endpointcost/lookup HTTP/1.1 POST /endpointcost/lookup HTTP/1.1
Host: alto.example.com Host: alto.example.com
Content-Length: TBA Content-Length: TBA
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9. Security Considerations 9. Security Considerations
The properties defined in this document present no security The properties defined in this document present no security
considerations beyond those in Section 15 of the base ALTO considerations beyond those in Section 15 of the base ALTO
specification [ALTO]. specification [ALTO].
However concerns addressed in Sections "15.1 Authenticity and However concerns addressed in Sections "15.1 Authenticity and
Integrity of ALTO Information", "15.2 Potential Undesirable Guidance Integrity of ALTO Information", "15.2 Potential Undesirable Guidance
from Authenticated ALTO Information" and "15.3 Confidentiality of from Authenticated ALTO Information" and "15.3 Confidentiality of
ALTO Information" remain of utmost importance. Indeed, TE ALTO Information" remain of utmost importance. Indeed, TE
performance is a highly sensitive ISP information and sharing TE performance is a highly sensitive ISP information, therefore, sharing
metric values in numerical mode requires full mutual confidence TE metric values in numerical mode requires full mutual confidence
between the entities managing the ALTO Server and Client. Numerical between the entities managing the ALTO Server and Client. Numerical
TE performance information will most likely be distributed by ALTO TE performance information will most likely be distributed by ALTO
Servers to Clients under strict and formal mutual trust agreements. Servers to Clients under strict and formal mutual trust agreements.
On the other hand, ALTO Clients must be cognizant on the risks On the other hand, ALTO Clients must be cognizant on the risks
attached to such information that they would have acquired outside attached to such information that they would have acquired outside
formal conditions of mutual trust. formal conditions of mutual trust.
10. IANA Considerations 10. IANA Considerations
IANA has created and now maintains the "ALTO Cost Metric Registry", IANA has created and now maintains the "ALTO Cost Metric Registry",
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11. References 11. References
11.1. Normative References 11.1. Normative References
[I-D.ietf-idr-te-pm-bgp] [I-D.ietf-idr-te-pm-bgp]
Previdi, S., Wu, Q., Gredler, H., Ray, S., Previdi, S., Wu, Q., Gredler, H., Ray, S.,
jefftant@gmail.com, j., Filsfils, C., and L. Ginsberg, jefftant@gmail.com, j., Filsfils, C., and L. Ginsberg,
"BGP-LS Advertisement of IGP Traffic Engineering "BGP-LS Advertisement of IGP Traffic Engineering
Performance Metric Extensions", draft-ietf-idr-te-pm- Performance Metric Extensions", draft-ietf-idr-te-pm-
bgp-04 (work in progress), October 2016. bgp-06 (work in progress), June 2017.
[I-D.ietf-ippm-initial-registry] [I-D.ietf-ippm-initial-registry]
Morton, A., Bagnulo, M., Eardley, P., and K. D'Souza, Morton, A., Bagnulo, M., Eardley, P., and K. D'Souza,
"Initial Performance Metric Registry Entries", draft-ietf- "Initial Performance Metric Registry Entries", draft-ietf-
ippm-initial-registry-02 (work in progress), October 2016. ippm-initial-registry-04 (work in progress), June 2017.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", March 1997. Requirement Levels", March 1997.
[RFC2679] Almes, G., Kalidindi, S., and M. Zekauskas, "A One-way [RFC2679] Almes, G., Kalidindi, S., and M. Zekauskas, "A One-way
Delay Metric for IPPM", RFC 2679, DOI 10.17487/RFC2679, Delay Metric for IPPM", RFC 2679, DOI 10.17487/RFC2679,
September 1999, <http://www.rfc-editor.org/info/rfc2679>. September 1999, <http://www.rfc-editor.org/info/rfc2679>.
[RFC2681] Almes, G., Kalidindi, S., and M. Zekauskas, "A Round-trip [RFC2681] Almes, G., Kalidindi, S., and M. Zekauskas, "A Round-trip
Delay Metric for IPPM", RFC 2681, DOI 10.17487/RFC2681, Delay Metric for IPPM", RFC 2681, DOI 10.17487/RFC2681,
skipping to change at page 26, line 26 skipping to change at page 27, line 26
11.2. Informative References 11.2. Informative References
[I-D.ietf-alto-deployments] [I-D.ietf-alto-deployments]
Stiemerling, M., Kiesel, S., Scharf, M., Seidel, H., and Stiemerling, M., Kiesel, S., Scharf, M., Seidel, H., and
S. Previdi, "ALTO Deployment Considerations", draft-ietf- S. Previdi, "ALTO Deployment Considerations", draft-ietf-
alto-deployments-16 (work in progress), July 2016. alto-deployments-16 (work in progress), July 2016.
[RFC6390] Clark, A. and B. Claise, "Framework for Performance Metric [RFC6390] Clark, A. and B. Claise, "Framework for Performance Metric
Development", RFC 6390, July 2011. Development", RFC 6390, July 2011.
Appendix A. Open Issue List
We need to consider to add Cellular endpoint format support in the
example, the Cellular endpoint format is specified in draft-
randriamasy-alto-cellular-adresses.
Authors' Addresses Authors' Addresses
Qin Wu Qin Wu
Huawei Huawei
101 Software Avenue, Yuhua District 101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012 Nanjing, Jiangsu 210012
China China
Email: bill.wu@huawei.com Email: bill.wu@huawei.com
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