ALTO Working Group Q. Wu
Internet-Draft Huawei
Intended status: Standards Track Y. Yang
Expires: December 29, 2014 Yale University
Y. Lee
D. Dhody
Huawei
S. Randriamasy
Alcatel-Lucent
June 27, 2014
ALTO Traffic Engineering Cost Metrics
draft-wu-alto-te-metrics-03
Abstract
Cost Metric is a basic concept in Application-Layer Traffic
Optimization (ALTO). It is used in both the Cost Map Service and the
Endpoint Cost Service. Future extensions to ALTO may also use Cost
Metric.
Different applications may benefit from different Cost Metrics. For
example, a Resource Consumer may prefer Resource Providers that have
low delay to the Resource Consumer. However the base ALTO protocol
[ALTO] has defined only a single cost metric, i.e., the generic
"routingcost" metric (Sec. 14.2 of ALTO base specification [ALTO]).
In this document, we define eleven Cost Metrics, derived from OSPF-TE
and ISIS-TE, to measure network delay, jitter, packet loss, hop
count, and bandwidth. The metrics defined in this document provide a
relatively comprehensive set of Cost Metrics for ALTO focusing on
traffic engineering (TE). Additional Cost Metrics such as financial
cost metrics may be defined in other documents.
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].
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
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working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on December 29, 2014.
Copyright Notice
Copyright (c) 2014 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
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
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to this document. Code Components extracted from this document must
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Data sources, computation of defined cost metrics . . . . . . 4
2.1. Data sources . . . . . . . . . . . . . . . . . . . . . . 4
2.2. Computation of metrics . . . . . . . . . . . . . . . . . 4
3. Metric: Delay . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Metric: Delay Jitter . . . . . . . . . . . . . . . . . . . . 6
5. Metric: Packet Loss . . . . . . . . . . . . . . . . . . . . . 8
6. Metric: Hop Count . . . . . . . . . . . . . . . . . . . . . . 10
7. Metric: Bandwidth . . . . . . . . . . . . . . . . . . . . . . 12
8. Metric: Maximum Bandwidth . . . . . . . . . . . . . . . . . . 13
9. Metric: Maximum Reserved Bandwdith . . . . . . . . . . . . . 14
10. Metric: Unavailable Reserved Bandwidth . . . . . . . . . . . 16
11. Metric: Residue Bandwidth . . . . . . . . . . . . . . . . . . 19
12. Metric: Available Bandwidth . . . . . . . . . . . . . . . . . 20
13. Metric: Utilized Bandwidth . . . . . . . . . . . . . . . . . 22
14. Security Considerations . . . . . . . . . . . . . . . . . . . 24
15. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25
16. References . . . . . . . . . . . . . . . . . . . . . . . . . 25
16.1. Normative References . . . . . . . . . . . . . . . . . . 25
16.2. Informative References . . . . . . . . . . . . . . . . . 26
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 26
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1. Introduction
Cost Metric is a basic concept in Application-Layer Traffic
Optimization (ALTO). It is used in both the Cost Map Service and the
Endpoint Cost Service. In particular, applications may benefit from
knowing network performance measured on several Cost Metrics. For
example, a more delay sensitive application may focus on latency, and
a more bandwidth-sensitive application may focus on available
bandwidth.
The objective of this document is to define eleven cost metrics,
listed in Table 1, to support the aforementioned applications.
Hence, this document extends the base ALTO protocol [ALTO], which
defines only a single cost metric, i.e., the generic "routingcost"
metric (Sec. 14.2 of ALTO base specification [ALTO]).
+-----------+--------------+------------------------+
| Namespace | Property | Reference |
+-----------+--------------+------------------------+
| | delay | [RFCxxxx], Section 3 |
| | jitter | [RFCxxxx], Section 4 |
| | pktloss | [RFCxxxx], Section 5 |
| | hopcount | [RFCxxxx], Section 6 |
| | bandwidth | [RFCxxxx], Section 7 |
| | maxbw | [RFCxxxx], Section 8 |
| | maxresbw | [RFCxxxx], Section 9 |
| | unresdbw | [RFCxxxx], Section 10 |
| | residbw | [RFCxxxx], Section 11 |
| | availbw | [RFCxxxx], Section 12 |
| | utilbw | [RFCxxxx], Section 13 |
+-----------+--------------+------------------------+
Table 1.
An ALTO server may provide a subset of the cost metrics defined in
this document. When an ALTO server supports a cost metric defined in
this document, the server SHOULD announce the metric in its IRD.
The definitions of a set of cost metrics can allow us to extend the
ALTO base protocol (e.g., allowing output and constraints use
different cost metrics), but such extensions are not in the scope of
this document.
One challenge in defining the metrics is that performance metrics
often depend on configuration parameters. For example, the value of
packet loss rate depends on the measurement interval and varies over
time. To handle this issue, ALTO server may collect data on time
periods covering the past, present or only collect data on present
time.
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Following the ALTO base protocol, this document uses JSON to specify
the value type of each defined metric. See [RFC4627] for JSON data
type specification.
2. Data sources, computation of defined cost metrics
The cost metrics defined in this document are similar, in that they
may use similar data sources and have similar issues in their
calculation. Hence, instead of specifying such issues for each
metric individually, we specify the common issue in this section.
2.1. Data sources
An ALTO server needs data sources to compute the cost metrics defined
in this document. This document does not define the exact data
sources. For example, the ALTO server may use log servers or the OAM
system as its data source [ALTO-DEPLOYMENT]. In particular, the cost
metrics defined in this document can be computed using routing
systems as the data sources. Mechanisms defined in [RFC3630],
[RFC3784], [OSPF-TE], [ISIS-TE], [BGP-LS] and [BGP-PM] that allow an
ALTO Server to retrieve and derive the necessary information to
compute the metrics that we define in this document.
2.2. Computation of metrics
An ALTO server process measurements from data sources to compute
exposed metrics. It may need performance data processing tasks such
as aggregating the results across multiple systems, removing
outliers, and creating additional statistics.
One specific challenge in defining the metrics in this document is
that these performance metrics depend on some configuration
parameters. For example, the value of packet loss rate depends on
the measurement interval and varies over time. If the ALTO server
uses aforementioned routing protocol based mechanisms as data
sources, then the measurement interval may be preconfigured by the
routing protocol. For example, Section 5 of [ISIS-TE] defines a
default measurement interval of 30 seconds. This document uses the
term Measurement Interval to refer to the measurement interval used
by the data sources. The Measurement Interval(s) of the data sources
can be different from the interval that this document defines the
metric. Hence, an ALTO server needs to resolve the mismatch, when it
happens. [TODO: Need more specification.]
Another issue of converting from data source measurements to ALTO
exposed metric values is that the measurement results that the ALTO
Server retrieves may be defined for only links, and hence, the server
will need to compose the link metrics to obtain path metrics used in
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services such as the Cost Map Service. In this definition, we define
the metrics to be independent of link or path, considering that
future ALTO extensions may define link-based services, and hence the
defined metrics should still be usable.
3. Metric: Delay
Cost Metric name:
Delay
Cost Metric string:
US-ASCII string 'delay'
Metric Description:
To specify spatial and temporal aggregated delay between the
specified source and destination or the time that the packet
spends to travel from source to destination. The spatial
aggregation unit is specified in the query context (e.g., PID to
PID, or endpoint to endpoint); and the temporal unit is specified
as the measurement interval in the query context.
Metric Unit:
The unit is microsecond.
Metric Value Type:
A single 'JSONNumber' type value containing a non-negative integer
component that may be followed by an exponent part.
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Example 1: Delay value on source-destination endpoint pairs
POST /endpointcost/lookup HTTP/1.1
Host: alto.example.com
Content-Length: TBA
Content-Type: application/alto-endpointcostparams+json
Accept: application/alto-endpointcost+json,application/alto-error+json
{
"cost-type": {"cost-mode" : "numerical",
"cost-metric" : "delay"},
"endpoints" : {
"srcs": [ "ipv4:192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv4:203.0.113.45"
]
}
}
HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta" :{
"cost-type": {"cost-mode" : "numerical",
"cost-metric" : "delay"
}
},
"endpoint-cost-map" : {
"ipv4:192.0.2.2": {
"ipv4:192.0.2.89" : 10,
"ipv4:198.51.100.34" : 20,
"ipv4:203.0.113.45" : 30,
}
}
}
4. Metric: Delay Jitter
Cost Metric name:
Delay jitter
Cost Metric string:
US-ASCII string 'jitter'
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Metric Description:
To specify spatial and temporal aggregated jitter (latency
variation) over the specified source and destination. The spatial
aggregation unit is specified in the query context (e.g., PID to
PID, or endpoint to endpoint); and the temporal unit is specified
as the measurement interval in the query context.
Metric Unit:
The unit is microsecond.
Metric Value Type:
A single 'JSONumber' type value containing an integer component
that may be followed by exponent part.
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Example 2: Delayjitter value on source-destination endpoint pairs
POST /endpointcost/lookup HTTP/1.1
Host: alto.example.com
Content-Length: TBA
Content-Type: application/alto-endpointcostparams+json
Accept: application/alto-endpointcost+json,application/alto-error+json
{
"cost-type": {"cost-mode" : "numerical",
"cost-metric" : "jitter"},
"endpoints" : {
"srcs": [ "ipv4:192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv4:203.0.113.45"
]
}
}
HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta": {
"cost type": {
"cost-mode": "numerical",
"cost-metric":"jitter"
}
},
"endpoint-cost-map": {
"ipv4:192.0.2.2": {
"ipv4:192.0.2.89" : 0
"ipv4:198.51.100.34" : 1
"ipv4:203.0.113.45" : 5
}
}
}
5. Metric: Packet Loss
Cost Metric name:
Packet loss
Cost Metric string:
US-ASCII string 'pktloss'
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Metric Description:
To specify spatial and temporal aggregated packet loss over the
specified source and destination. The spatial aggregation unit is
specified in the query context (e.g., PID to PID, or endpoint to
endpoint); and the temporal unit is specified as the measurement
interval in the query context.
Metric Unit:
The unit is percentile.
Metric Value Type:
A single number value containing an integer component that may be
followed by a fraction part and/or an exponent part.
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Example 3: pktloss value on source-destination endpoint pairs
POST /endpointcost/lookup HTTP/1.1
Host: alto.example.com
Content-Length: TBA
Content-Type: application/alto-endpointcostparams+json
Accept: application/alto-endpointcost+json,application/alto-error+json
{
"cost-type": {"cost-mode" : "numerical",
"cost-metric" : "pktloss"},
"endpoints" : {
"srcs": [ "ipv4:192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv4:203.0.113.45"
]
}
}
HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta": {
"cost type": {
"cost-mode": "numerical",
"cost-metric":"pktloss"}
}
},
"endpoint-cost-map": {
"ipv4:192.0.2.2": {
"ipv4:192.0.2.89" : 0,
"ipv4:198.51.100.34": 1,
"ipv4:203.0.113.45" : 2,
}
}
}
6. Metric: Hop Count
The metric hopcount is mentioned in [ALTO] as an example. This
section further clarifies its properties.
Cost Metric name:
Hop count
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Cost Metric string:
US-ASCII string 'hopcount'
Metric Description:
To specify the number of hops in the path between the source
endpoint and the destination endpoint.
[Editor Note: Need to specify which level (AS, IP perhaps),
details TBD for multiple-layer aspect.]
Metric Unit:
The unit is integer number.
Metric Value Type:
A single 'JSONNumber' type value containing an integer component.
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Example 4: hopcount value on source-destination endpoint pairs
POST /endpointcost/lookup HTTP/1.1
Host: alto.example.com
Content-Length: TBA
Content-Type: application/alto-endpointcostparams+json
Accept: application/alto-endpointcost+json,application/alto-error+json
{
"cost-type": {"cost-mode" : "numerical",
"cost-metric" : "hopcount"},
"endpoints" : {
"srcs": [ "ipv4:192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv4:203.0.113.45"
]
}
}
HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta": {
"cost type": {
"cost-mode": "numerical",
"cost-metric":"hopcount"}
}
},
"endpoint-cost-map": {
"ipv4:192.0.2.2": {
"ipv4:192.0.2.89" : 5,
"ipv4:198.51.100.34": 3,
"ipv4:203.0.113.45" : 2,
}
}
}
7. Metric: Bandwidth
Cost Metric name:
Bandwidth
Cost Metric string:
US-ASCII string 'bandwidth'
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Metric Description:
To specify spatial and temporal aggregated bandwidth over the
specified source and destination. The spatial aggregation unit is
specified in the query context (e.g., PID to PID, or endhost to
endhost); and the temporal unit is specified as the measurement
interval in the query context.
This is just a definition of a class of cost metric 'bandwidth'.
The use of this cost metric is always in conjunction with what it
represents, which could be Max Bandwidth (maxbw), Residual
Bandwidth (residuebw) etc.
Metric Unit:
The units are bytes per second.
Metric Value Type:
A single 'JSONNumber' type value containing an integer component ,
which may be followed by a fraction part and/or an exponent part.
8. Metric: Maximum Bandwidth
Cost Metric name:
Maximum Bandwidth
Cost Metric string:
US-ASCII string 'maxbw'
Metric Description:
To specify spatial and temporal maximum bandwidth over the
specified source and destination. The spatial aggregation unit is
specified in the query context (e.g., PID to PID, or endhost to
endhost); and the temporal unit is specified as the measurement
interval in the context interval.
Metric Unit and Metric Value Type:
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See definition for the Bandwidth Cost Metric.
Example 5: maxbw value on source-destination endpoint pairs
POST/ endpointcost/lookup HTTP/1.1
Host: alto.example.com
Content-Length: TBA
Content-Type: application/alto-endpointcostparams+json
Accept: application/alto-endpointcost+json,application/alto-error+json
{
"cost-type": { "cost-mode": "numerical",
"cost-metric": "maxbw"},
"endpoints": {
"srcs": [ "ipv4 : 192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv4:203.0.113.45"
]
}
}
HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta": {
"cost-type": {
"cost-mode": "numerical",
"cost-metric": "maxbw"
}
},
"endpoint-cost-map": {
"ipv4:192.0.2.2": {
"ipv4:192.0.2.89": 0,
"ipv4:198.51.100.34" : 2000,
"ipv4:203.0.113.45": 5000,
}
}
}
9. Metric: Maximum Reserved Bandwdith
Cost Metric name:
Maximum Reserved Bandwidth
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Cost Metric string:
US-ASCII string 'maxresbw'
Metric Description:
To specify spatial and temporal maximum reserved bandwidth over
the specified source and destination. The spatial aggregation
unit is specified in the query context (e.g., PID to PID, or
endpoint to endpoint); and the temporal unit is specified as the
measurement interval in the query context.
Metric Unit and Value Type:
See definition of the Bandwidth Cost Metric.
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Example 6: maxresbw value on source-destination endpoint pairs
POST/ endpointcost/lookup HTTP/1.1
Host: alto.example.com
Content-Length: TBA
Content-Type: application/alto-endpointcostparams+json
Accept: application/alto-endpointcost+json,application/alto-error+json
{
"cost-type" { "cost-mode": "numerical",
"cost-metric": "maxresbw"},
"endpoints": {
"srcs": [ "ipv4 : 192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv4:203.0.113.45"
]
}
}
HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta": {
"cost-type": {
"cost-mode": "numerical",
"cost-metric": "maxresbw"
}
},
" endpoint-cost-map": {
"ipv4:192.0.2.2" {
"ipv4:192.0.2.89" : 0,
"ipv4:198.51.100.34": 2000,
"ipv4:203.0.113.45": 5000,
}
}
}
10. Metric: Unavailable Reserved Bandwidth
Cost Metric name:
Unavailable Reserved Bandwidth
Cost Metric string:
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US-ASCII string 'unresbw'
Metric Description:
To specify spatial and temporal unavailable reserved bandwidth
over the specified source and destination. The values correspond
to the bandwidth that can be reserved with a setup priority of 0
through 7. Therefore this metric is endcoded as an array of 8
values. The spatial aggregation unit is specified in the query
context (e.g., PID to PID, or endpoint to endpoint); and the
temporal unit is specified as the measurement interval in the
query context.
Metric Unit and Value Type:
See definition for the bandwidth Cost Metric.
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Example 7: unresbw value on source-destination endpoint pairs
In this example, the Collection method specifies that the
'unresbw' values are defined as the 'unavailable bandwidth' specified
in section 2.5.8 of RFC3630: 8 unavailable bandwidth value are
reported in the same OSPF message using the same TLV. Each value
is corresponding to the bandwidth that can be reserved with a setup
priority of 0 through 7.
POST/ endpointcost/lookup HTTP/1.1
Host: alto.example.com
Content-Length: TBA
Content-Type: application/alto-endpointcostparams+json
Accept: application/alto-endpointcost+json,application/alto-error+json
{
"cost-type" { "cost-mode": "numerical",
"cost-metric": "unresbw[1,8]" },
"endpoints": {
"srcs": [ "ipv4:192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv4:203.0.113.45"
]
}
}
HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta": {
"cost-type": {
"cost-mode": "numerical",
"cost-metric": "unresbw[1,8]"
}
},
"endpoint-cost-map" {
"ipv4:192.0.2.2" {
"ipv4:192.0.2.89" : [0,0,0,0,0,0,0,0],
"ipv4:198.51.100.34": [0,0,0,0,0,0,0,2000],
"ipv4:203.0.113.45": [0,0,0,0,0,0,0,5000],
}
}
}
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11. Metric: Residue Bandwidth
Cost Metric name:
Residue Bandwidth
Cost Metric string:
US-ASCII string 'residbw'
Metric Description:
To specify spatial and temporal residual bandwidth over the
specified source and destination. The spatial aggregation unit is
specified in the query context (e.g., PID to PID, or endpoint to
endpoint); and the temporal unit is specified as the measurement
interval in the query context.
Metric Unit and Value Type:
See definition of the general Bandwidth.
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Example 8: residuebw value on source-destination endpoint pairs
POST/ endpointcost/lookup HTTP/1.1
Host: alto.example.com
Content-Length: TBA
Content-Type: application/alto-endpointcostparams+json
Accept: application/alto-endpointcost+json,application/alto-error+json
{
"cost-type": { "cost-mode": "numerical",
"cost-metric": "residubw"},
"endpoints": {
"srcs": [ "ipv4 : 192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv4:203.0.113.45"
]
}
}
HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta": {
"cost-type" {
"cost-mode": "numerical",
"cost-metric": "residubw"
}
},
"endpoint-cost-map" {
"ipv4:192.0.2.2" {
"ipv4:192.0.2.89" : 0,
"ipv4:198.51.100.34": 2000,
"ipv4:203.0.113.45": 5000,
}
}
}
12. Metric: Available Bandwidth
Cost Metric name:
Available Bandwidth
Cost Metric string:
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US-ASCII string 'availbw'
Metric Description:
To specify spatial and temporal availaible bandwidth over the
specified source and destination. The spatial aggregation unit is
specified in the query context (e.g., PID to PID, or endpoint to
endpoint); and the temporal unit is specified as the measurement
interval in the query context.
Metric Unit and Value Type:
See definition of the general Bandwidth.
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Example 9: availbw value on source-destination endpoint pairs
POST /endpointcost/lookup HTTP/1.1
Host: alto.example.com
Content-Length: TBA
Content-Type: application/alto-endpointcostparams+json
Accept: application/alto-endpointcost+json,application/alto-error+json
{
"cost-type": { "cost-mode": "numeric",
"cost-metric": "availbw"},
"endpoints": {
"srcs": [ "ipv4 : 192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv4:203.0.113.45"
]
}
}
HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta": {
"cost-type": {
"cost-mode": "numeric",
"cost-metric": "availbw"
}
},
"endpoint-cost-map": {
"ipv4:192.0.2.2" {
"ipv4:192.0.2.89" : [6,5,7,8,4,10,7,6],
"ipv4:198.51.100.34" : [7,4,6,8,5,9,6,7],
"ipv4:203.0.113.45" : [7,6,8,5,7,9,6,8],
}
}
}
13. Metric: Utilized Bandwidth
Cost Metric name:
Utilized Bandwidth
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Cost Metric string:
US-ASCII string 'utilbw'
Metric Description:
To specify spatial and temporal utilized bandwidth over the
specified source and destination. The spatial aggregation unit is
specified in the query context (e.g., PID to PID, or endpoint to
endpoint); and the temporal unit is specified as the measurement
interval in the query context.
Metric Unit and Value Type:
See definition of the general Bandwidth.
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Example 10: utilbw value on source-destination endpoint pairs
POST /endpointcost/lookup HTTP/1.1
Host: alto.example.com
Content-Length: TBA
Content-Type: application/alto-endpointcostparams+json
Accept: application/alto-endpointcost+json,application/alto-error+json
{
"cost-type": {"cost-mode" : "numerical",
"cost-metric" : "utilbw"},
"endpoints": {
"srcs" : [ "ipv4 : 192.0.2.2" ],
"dsts" : [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv4:203.0.113.45"
]
}
}
HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta": {
"cost type": {
"cost-mode": "numerical",
"cost-metric": "utilbw"
}
},
"endpoint-cost-map": {
"ipv4:192.0.2.2" {
"ipv4:192.0.2.89" : 0,
"ipv4:198.51.100.34" : 2000,
"ipv4:203.0.113.45" : 5000,
}
}
}
14. Security Considerations
The properties defined in this document present no security
considerations beyond those in Section 15 of the base ALTO
specification [ALTO].
However concerns addressed in Sections "15.1 Authenticity and
Integrity of ALTO Information", "15.2 Potential Undesirable Guidance
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from Authenticated ALTO Information" and "15.3 Confidentiality of
ALTO Information" remain of utmost importance. Indeed, TE
performance is a highly sensitive ISP information and sharing TE
metric values in numerical mode requires full mutual confidence
between the entities managing the ALTO Server and Client. Numerical
TE performance information will most likely be distributed by ALTO
Servers to Clients under strict and formal mutual trust agreements.
One the other hand, ALTO Clients must be cognizant on the risks
attached to such information that they would have acquired outside
formal conditions of mutual trust.
15. IANA Considerations
IANA has added the following entries to the ALTO cost map Properties
registry, defined in Section 3 of [RFCXXX].
+-----------+--------------+------------------------+
| Namespace | Property | Reference |
+-----------+--------------+------------------------+
| | delay | [RFCxxxx], Section 3 |
| | jitter | [RFCxxxx], Section 4 |
| | pktloss | [RFCxxxx], Section 5 |
| | hopcount | [RFCxxxx], Section 6 |
| | bandwidth | [RFCxxxx], Section 7 |
| | maxbw | [RFCxxxx], Section 8 |
| | maxresbw | [RFCxxxx] Section 9 |
| | unresdbw | [RFCxxxx], Section 10 |
| | residbw | [RFCxxxx], Section 11 |
| | availbw | [RFCxxxx], Section 12 |
| | utilbw | [RFCxxxx], Section 13 |
+-----------+--------------+------------------------+
16. References
16.1. Normative References
[ALTO] Alimi, R., "ALTO Protocol", ID draft-ietf-alto-protocol-
16, May 2013.
[BGP-LS] Gredler, H., "North-Bound Distribution of Link-State and
TE Information using BGP", ID draft-ietf-idr-ls-
distribution-03, May 2013.
[BGP-PM] Wu, Q., "BGP attribute for North-Bound Distribution of
Traffic Engineering (TE) performance Metrics", ID draft-
wu-idr-te-pm-bgp-02, October 2013.
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[ISIS-TE] Giacalone, S., "ISIS Traffic Engineering (TE) Metric
Extensions", ID draft-ietf-isis-te-metric-extensions-01,
October 2013.
[OSPF-TE] Giacalone, S., "OSPF Traffic Engineering (TE) Metric
Extensions", ID draft-ietf-ospf-te-metric-extensions-04,
June 2013.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", March 1997.
[RFC4627] Crockford, D., "The application/json Media Type for
JavaScript Object Notation (JSON)", RFC 4627, July 2006.
[RFC5234] Crocker, D., "Augmented BNF for Syntax Specifications:
ABNF", RFC 5234, January 2008.
16.2. Informative References
[ALTO-DEPLOYMENT]
Stiemerling, M., Kiesel, S., Previdi, S., and M. Scharf,
"ALTO Deployment Considerations", ID draft-ietf-alto-
deployments-08, October 2013.
[RFC6390] Clark, A. and B. Claise, "Framework for Performance Metric
Development", RFC 6390, July 2011.
Authors' Addresses
Qin Wu
Huawei
101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012
China
Email: sunseawq@huawei.com
Y. Richard Yang
Yale University
51 Prospect St
New Haven, CT 06520
USA
Email: yry@cs.yale.edu
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Young Lee
Huawei
1700 Alma Drive, Suite 500
Plano, TX 75075
USA
Email: leeyoung@huawei.com
Dhruv Dhody
Huawei
Leela Palace
Bangalore, Karnataka 560008
INDIA
Email: dhruv.ietf@gmail.com
Sabine Randriamasy
Alcatel-Lucent
Route de Villejust
Nozay 91460
FRANCE
Email: Sabine.Randriamasy@alcatel-lucent.com
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