ALTO Working Group Q. Wu
Internet-Draft Huawei
Intended status: Standards Track Y. Yang
Expires: April 24, 2019 Yale University
Y. Lee
D. Dhody
Huawei
S. Randriamasy
Nokia Bell Labs
October 21, 2018
ALTO Performance Cost Metrics
draft-ietf-alto-performance-metrics-05
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.
Different applications may benefit from different Cost Metrics. For
example, a Resource Consumer may prefer Resource Providers that offer
a low delay delivery to the Resource Consumer. However the base ALTO
protocol [ALTO] has documented only one single cost metric, i.e., the
generic "routingcost" metric (Sec. 14.2 of ALTO base specification
[ALTO]).
This document, proposes a set of Cost Metrics, derived and aggregated
from routing protocols with different granularity and scope, such as
BGP-LS,OSPF-TE and ISIS-TE, or from end-to-end traffic management
tools. It currently documents Network Performance Cost Metrics
reporting on network delay, jitter, packet loss, hop count, and
bandwidth. These metrics may be exposed by an ALTO Server to allow
applications to determine "where" to connect based on network
performance criteria. Additional Cost Metrics involving ISP specific
considerations or other network technologies may be documented in
further versions of this draft.
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].
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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
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://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 April 24, 2019.
Copyright Notice
Copyright (c) 2018 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
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
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.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Challenges on data sources and computation of ALTO
performance metrics . . . . . . . . . . . . . . . . . . . . . 5
2.1. Data sources Challenge . . . . . . . . . . . . . . . . . 5
2.2. ALTO performance metrics Computation Challenges . . . . . 5
2.2.1. Configuration Parameters Challenge . . . . . . . . . 5
2.2.2. Availability of end to end path values Challenge . . 6
3. Cost Metric: OWDelay . . . . . . . . . . . . . . . . . . . . 6
4. Cost Metric: RTT . . . . . . . . . . . . . . . . . . . . . . 8
5. Cost Metric: PDV . . . . . . . . . . . . . . . . . . . . . . 10
6. Cost Metric: Hop Count . . . . . . . . . . . . . . . . . . . 12
7. Cost Metric: Packet Loss . . . . . . . . . . . . . . . . . . 14
8. Cost Metric: Throughput . . . . . . . . . . . . . . . . . . . 16
9. Traffic Engineering Performance Cost Metrics . . . . . . . . 18
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9.1. Cost Metric: Link Maximum Reservable Bandwidth . . . . . 19
9.2. Cost Metric: Link Residue Bandwidth . . . . . . . . . . . 20
10. Security Considerations . . . . . . . . . . . . . . . . . . . 22
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 23
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 23
12.1. Normative References . . . . . . . . . . . . . . . . . . 23
12.2. Informative References . . . . . . . . . . . . . . . . . 25
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 25
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.
This document introduces a set of new cost metrics, listed in
Table 1, to support the aforementioned applications and allow them to
determine "where" to connect based on network performance criteria.
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 |
+----------+--------------+----------------------------------------+
| | owdelay | See Section 3,[RFC2679] Section 3.6 |
| | rtt | See Section 4,[RFC2681] Section 2.6 |
| | pdv | See Section 5,[RFC3393] Section 2.6 |
| | hopcount | See Section 6,[RFC7285] |
| | pktloss | See Section 7,[RFC7680] Section 2.6 |
| | throughput | See Section x, [RFC6349] Section 3.3 |
| | maxresbw | See Section 8.1,[RFC5305] Section 3.5 |
| | residbw | See Section 8.2,[RFC7810] Section 4.5 |
+----------+--------------+----------------------------------------+
Table 1.
The purpose of this draft is to list the metrics likely to be exposed
to ALTO Clients, including those already specified in other
standardization groups and as such it does not claim novelty on all
the specified metrics. Some metrics may have values produced by
standard measurement methods such as those specified in 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 specifications.
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An ALTO server may provide a subset of the cost metrics described in
this document. These cost metrics can be retrieved and aggregated
from routing protocols or other traffic measurement management tools
(See Figure 1). Note that these cost metrics are optional and not
all them need to be exposed to applications. For example, those that
are subject to privacy concerns should not be provided to
unauthorized ALTO clients.
+--------+ +--------+ +--------+
| Client | | Client | | Client |
+----^---+ +---^----+ +---^----+
| | |
+-----------|-----------+
NBI |ALTO protocol
|
|
+--+-----+ retrieval +---------+
| ALTO |<----------------| Routing |
| Server | and aggregation| |
| |<-------------+ | Protocol|
+--------+ | +---------+
|
| +---------+
| |Management
---| |
| Tool |
+---------+
Figure 1.End-to-End Path Cost Metrics Exposing
When an ALTO server supports a cost metric defined in this document,
it MUST announce this metric in its IRD.
Additionally, future versions of this document may define network
metric values that stem from both measurements and provider policies
such as many metrics related to end-to-end path bandwidth.
As for the reliability and trust in the exposed metric values,
applications SHOULD rapidly give up using ALTO-based guidance if they
feel the exposed information does not preserve their performance
level or even degrades it.
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.
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2. Challenges on data sources and computation of ALTO performance
metrics
2.1. Data sources Challenge
An ALTO server needs data sources to compute the cost metrics
described 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
[RFC2681],[RFC3393],[RFC7679],[RFC7680],[RFC3630], [RFC3784],
[RFC7471], [RFC7810], [RFC7752] and [BGP-PM] that allow an ALTO
Server to retrieve and derive the necessary information to compute
the metrics that we describe in this document.
One challenge lies in the data sources originating the ALTO metric
values. The very important purpose of ALTO is to guide application
traffic with provider network centric information that may be exposed
to ALTO Clients in the form of network performance metric values.
Not all of these metrics have values produced by standardized
measurement methods or routing protocols. Some of them involve
provider-centric policy considerations. Some of them may describe
wireless or cellular networks. To reliably guide users and
applications while preserving provider privacy, ALTO performance
metric values may also add abstraction to measurements or provide
unitless performance scores.
2.2. ALTO performance metrics Computation Challenges
The metric values exposed by an ALTO server may result from
additional processing on measurements from data sources to compute
exposed metrics. This may involve data processing tasks such as
aggregating the results across multiple systems, removing outliers,
and creating additional statistics. There are two challenges on
computation of ALTO performance metrics.
2.2.1. Configuration Parameters Challenge
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, an ALTO server
may collect data on time periods covering the previous and current
time or only collect data on present time. The ALTO server may
further aggregate these data to provide an abstract and unified view
that can be more useful to applications. To make the ALTO client
better understand how to use these performance data, the ALTO server
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may provide the client with the validity period of the exposed metric
values.
2.2.2. Availability of end to end path values Challenge
Applications value information relating to bandwidth availability
where as bandwidth related metrics can often be only measured at the
link level. This document specifies a set of link-level bandwidth
related values that may be exposed as such by an ALTO server. The
server may also expose other metrics derived from their aggregation
and having different levels of endpoint granularity, e.g. link
endpoints or session endpoints. The metric specifications may also
expose the utilized aggregation laws.
3. Cost Metric: OWDelay
Metric name:
One Way Delay
Metric Description:
To specify spatial and temporal aggregated delay of a stream of
packets exchanged between the specified source and destination or
the time that the packet spends to travel from source to
destination. The spatial aggregation level is specified in the
query context (e.g., PID to PID, or endpoint to endpoint).
Method of Measurement or Calculation:
See section 8.3 of [I-D.ietf-ippm-initial-registry] for
Measurement Method.
Units of Measurement:
See section 8.4.3 of [I-D.ietf-ippm-initial-registry] for
Measurement Unit. The unit is expressed in milliseconds in this
document.
Measurement Point(s) with Potential Measurement Domain:
See section 2.1, Data sources.
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Measurement Timing:
See section 8.3.5 of [I-D.ietf-ippm-initial-registry] for
Measurement Timing.
Use and Applications:
The Metric value Type is a single 'JSONNumber' type value
containing a non-negative integer component that may be followed
by an exponent part. The Cost Mode is encoded as a US-ASCII
string.
This metric could be used as a cost metric constraint attribute
used either together with cost metric attribute 'routingcost' or
on its own or as a returned cost metric in the response.
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" : "owdelay"},
"endpoints" : {
"srcs": [ "ipv4:192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv6:2000::1:2345:6789:abcd"
]
}
}
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HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta" :{
"cost-type": {"cost-mode" : "numerical",
"cost-metric" : "owdelay"
}
},
"endpoint-cost-map" : {
"ipv4:192.0.2.2": {
"ipv4:192.0.2.89" : 10,
"ipv4:198.51.100.34" : 20,
"ipv6:2000::1:2345:6789:abcd" : 30,
}
}
}
4. Cost Metric: RTT
Metric name:
Round Trip Delay
Metric Description:
To specify spatial and temporal aggregated round trip delay
between the specified source and destination or the time that the
packet spends to travel from source to destination and then from
destination to source. The spatial aggregation level is specified
in the query context (e.g., PID to PID, or endpoint to endpoint).
Method of Measurement or Calculation:
See section 4.3 of [I-D.ietf-ippm-initial-registry] for
Measurement Method.
Units of Measurement:
See section 4.4.3 of [I-D.ietf-ippm-initial-registry] for
Measurement Unit. The unit is expressed in milliseconds in this
document.
Measurement Point(s) with Potential Measurement Domain:
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See section 2.1, Data sources.
Measurement Timing:
See section 4.3.5 of [I-D.ietf-ippm-initial-registry] for
Measurement Timing.
Use and Applications:
See section 3 for use and application.
Example 2: Round Trip 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" : "rtt"},
"endpoints" : {
"srcs": [ "ipv4:192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv6:2000::1:2345:6789:abcd"
]
}
}
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HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta" :{
"cost-type": {"cost-mode" : "numerical",
"cost-metric" : "rtt"
}
},
"endpoint-cost-map" : {
"ipv4:192.0.2.2": {
"ipv4:192.0.2.89" : 4,
"ipv4:198.51.100.34" : 3,
"ipv6:2000::1:2345:6789:abcd" : 2,
}
}
}
5. Cost Metric: PDV
Metric name:
Packet Delay Variation
Metric Description:
To specify spatial and temporal aggregated jitter (packet delay
variation) with respect to the minimum delay observed on the
stream over the specified source and destination. The spatial
aggregation level is specified in the query context (e.g., PID to
PID, or endpoint to endpoint).
Method of Measurement or Calculation:
See section 5.3 of [I-D.ietf-ippm-initial-registry] for
Measurement Method.
Units of Measurement:
See section 5.4.4 of [I-D.ietf-ippm-initial-registry] for
Measurement Unit. The unit is expressed in milliseconds in this
document.
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Measurement Point(s) with Potential Measurement Domain:
See section 2.1, Data sources.
Measurement Timing:
See section 5.3.5 of [I-D.ietf-ippm-initial-registry] for
Measurement Timing.
Use and Applications:
See section 3 for use and application.
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Example 3: PDV 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" : "pdv"},
"endpoints" : {
"srcs": [ "ipv4:192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv6:2000::1:2345:6789:abcd"
]
}
}
HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta": {
"cost type": {
"cost-mode": "numerical",
"cost-metric":"delayjitter"
}
},
"endpoint-cost-map": {
"ipv4:192.0.2.2": {
"ipv4:192.0.2.89" : 0
"ipv4:198.51.100.34" : 1
"ipv6:2000::1:2345:6789:abcd" : 5
}
}
}
6. Cost Metric: Hop Count
The metric hopcount is mentioned in [ALTO] as an example. This
section further clarifies its properties.
Metric name:
Hop count
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Metric Description:
To specify the number of hops in the path between the source
endpoint and the destination endpoint. The hop count is a basic
measurement of distance in a network and can be exposed as Router
Hops, IP hops in direct relation to the routing protocols
originating this information. It might also result from the
aggregation of such information.
Method of Measurement or Calculation:
The hop count can and calculated based on the number of routers
from the source endpoint through which data must pass to reach the
destination endpoint.
Units of Measurement:
The unit is integer number.
Measurement Point(s) with Potential Measurement Domain:
The hop count can be measured at the source endpoint by
traceroute.
Measurement Timing:
Upon need, the traceroute can use UDP probe message or other
implementations that use ICMP and TCP to discover the hop counts
along the path from source endpoint to destination endpoint.
Use and Applications:
See section 3 for use and application.
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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",
"ipv6:2000::1:2345:6789:abcd"
]
}
}
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,
"ipv6:2000::1:2345:6789:abcd" : 2,
}
}
}
7. Cost Metric: Packet Loss
Metric name:
Packet loss
Metric Description:
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To specify spatial and temporal aggregated packet loss over the
specified source and destination. The spatial aggregation level
is specified in the query context (e.g., PID to PID, or endpoint
to endpoint).
Method of Measurement or Calculation:
See section 2.6 of [RFC7680] for Measurement Method.
Units of Measurement:
The unit is percentile.
Measurement Point(s) with Potential Measurement Domain:
See section 2.1, Data sources.
Measurement Timing:
See section 2 and section3 of [RFC7680] for Measurement Timing.
Use and Applications:
See section 3 for use and application.
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Example 5: 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",
"ipv6:2000::1:2345:6789:abcd"
]
}
}
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": 0,
"ipv6:2000::1:2345:6789:abcd" : 0,
}
}
}
8. Cost Metric: Throughput
Metric name:
Throughput
Metric Description:
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To specify spatial and temporal throughput over the specified
source and destination. The spatial aggregation level is
specified in the query context (e.g., PID to PID, or endpoint to
endpoint).
Method of Measurement or Calculation:
See section 3.3 of [RFC6349] for Measurement Method.
Units of Measurement:
The unit is Mbps.
Measurement Point(s) with Potential Measurement Domain:
See section 2.1, Data sources.
Measurement Timing:
Similar to RTT,See section 4.3.5 of [I-D.ietf-ippm-initial-
registry] for Measurement Timing.
Use and Applications:
See section 3 for use and application.
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Example 5: throughtput 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" : "throughput"},
"endpoints" : {
"srcs": [ "ipv4:192.0.2.2" ],
"dsts": [
"ipv4:192.0.2.89",
"ipv4:198.51.100.34",
"ipv6:2000::1:2345:6789:abcd"
]
}
}
}
HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta": {
"cost type": {
"cost-mode": "numerical",
"cost-metric":"throughput"}
}
},
"endpoint-cost-map": {
"ipv4:192.0.2.2": {
"ipv4:192.0.2.89" : 25.6,
"ipv4:198.51.100.34": 12.8,
"ipv6:2000::1:2345:6789:abcd" : 42.8,
}
}
}
9. Traffic Engineering Performance Cost Metrics
This section introduces ALTO network performance metrics that may be
aggregated from network metrics measured on links and specified in
other documents. In particular, the bandwidth related metrics
specified in this section are only available through link level
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measurements. For some of these metrics, the ALTO Server may further
expose aggregated values while specifying the aggregation laws.
9.1. Cost Metric: Link Maximum Reservable Bandwidth
Metric name:
Maximum Reservable Bandwidth
Metric Description:
To specify spatial and temporal maximum reservable bandwidth over
the specified source and destination. The value is corresponding
to the maximum bandwidth that can be reserved (motivated from RFC
3630 Sec. 2.5.7.). The spatial aggregation unit is specified in
the query context (e.g., PID to PID, or endpoint to endpoint).
Method of Measurement or Calculation:
Maximum Reserveable Bandwidth is the bandwidth measured between
two directly connected IS-IS neighbors or OSPF neighbors, See
section 3.5 of [RFC5305] for Measurement Method.
Units of Measurement:
The unit of measurement is byte per seconds.
Measurement Point(s) with Potential Measurement Domain:
See section 2.1, Data sources.
Measurement Timing:
See section 3.5 of [RFC5305] and section 5 of [RFC7810] for
Measurement Timing.
Use and Applications:
See section 3 for use and application.
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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",
"ipv6:2000::1:2345:6789:abcd"
]
}
}
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,
"ipv6:2000::1:2345:6789:abcd": 5000,
}
}
}
9.2. Cost Metric: Link Residue Bandwidth
Metric name:
Residue Bandwidth
Metric Description:
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To specify spatial and temporal residual bandwidth over the
specified source and destination. The value is calculated by
subtracting tunnel reservations from Maximum Bandwidth (motivated
from [RFC7810], Sec.4.5.). The spatial aggregation unit is
specified in the query context (e.g., PID to PID, or endpoint to
endpoint).
Method of Measurement or Calculation:
Residue Bandwidth is the Unidirectional Residue bandwidth measured
between two directly connected IS-IS neighbors or OSPF neighbors,
See section 4.5 of [RFC7810] for Measurement Method.
Units of Measurement:
The unit of measurement is byte per seconds.
Measurement Point(s) with Potential Measurement Domain:
See section 2.1, Data sources.
Measurement Timing:
See section 5 of [RFC7810] for Measurement Timing.
Use and Applications:
See section 3 for use and application.
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Example 7: residbw 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",
"ipv6:2000::1:2345:6789:abcd"
]
}
}
HTTP/1.1 200 OK
Content-Length: TBA
Content-Type: application/alto-endpointcost+json
{
"meta": {
"cost-type" {
"cost-mode": "numerical",
"cost-metric": "residbw"
}
},
"endpoint-cost-map" {
"ipv4:192.0.2.2" {
"ipv4:192.0.2.89" : 0,
"ipv4:198.51.100.34": 2000,
"ipv6:2000::1:2345:6789:abcd": 5000,
}
}
}
10. 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, therefore, 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.
On 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.
11. IANA Considerations
IANA has created and now maintains the "ALTO Cost Metric Registry",
listed in Section 14.2, Table 3 of [RFC7285]. This registry is
located at <http://www.iana.org/assignments/alto-protocol/alto-
protocol.xhtml#cost-metrics>. This document requests to add the
following entries to "ALTO Cost Meric Registry".
+----------+------------+----------------------------------------------+
|Namespace | Property | Reference |
+----------+------------+----------------------------------------------+
| | owdelay | [thisdraft] Section 3,[RFC2679] Section 3.6 |
| | rtt | [thisdraft] Section 4,[RFC2681],Section 2.6 |
| | pdv | [thisdraft] Section 5,[RFC3393],Section 2.6 |
| | hopcount | [thisdraft] Section 6,[RFC7285] |
| | pktloss | [thisdraft] Section 7,[RFC7680],Section 2.6 |
| | throughput | [thisdraft],[RFC6349],Section3.3 |
| | maxresbw | [thisdraft] Section 8.1,[RFC5305],Section 3.5|
| | residbw | [thisdraft] Section 8.2,[RFC7810],Section 4.5|
+----------+------------+----------------------------------------------+
12. References
12.1. Normative References
[I-D.ietf-idr-te-pm-bgp]
Ginsberg, L., Previdi, S., Wu, Q., Tantsura, J., and C.
Filsfils, "BGP-LS Advertisement of IGP Traffic Engineering
Performance Metric Extensions", draft-ietf-idr-te-pm-
bgp-14 (work in progress), October 2018.
[I-D.ietf-ippm-initial-registry]
Morton, A., Bagnulo, M., Eardley, P., and K. D'Souza,
"Initial Performance Metric Registry Entries", draft-ietf-
ippm-initial-registry-07 (work in progress), June 2018.
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[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", March 1997.
[RFC2679] Almes, G., Kalidindi, S., and M. Zekauskas, "A One-way
Delay Metric for IPPM", RFC 2679, DOI 10.17487/RFC2679,
September 1999, <https://www.rfc-editor.org/info/rfc2679>.
[RFC2681] Almes, G., Kalidindi, S., and M. Zekauskas, "A Round-trip
Delay Metric for IPPM", RFC 2681, DOI 10.17487/RFC2681,
September 1999, <https://www.rfc-editor.org/info/rfc2681>.
[RFC3393] Demichelis, C. and P. Chimento, "IP Packet Delay Variation
Metric for IP Performance Metrics (IPPM)", RFC 3393,
DOI 10.17487/RFC3393, November 2002,
<https://www.rfc-editor.org/info/rfc3393>.
[RFC4627] Crockford, D., "The application/json Media Type for
JavaScript Object Notation (JSON)", RFC 4627,
DOI 10.17487/RFC4627, July 2006,
<https://www.rfc-editor.org/info/rfc4627>.
[RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", STD 68, RFC 5234,
DOI 10.17487/RFC5234, January 2008,
<https://www.rfc-editor.org/info/rfc5234>.
[RFC5305] Li, T. and H. Smit, "IS-IS Extensions for Traffic
Engineering", RFC 5305, DOI 10.17487/RFC5305, October
2008, <https://www.rfc-editor.org/info/rfc5305>.
[RFC6349] Constantine, B., Forget, G., Geib, R., and R. Schrage,
"Framework for TCP Throughput Testing", RFC 6349,
DOI 10.17487/RFC6349, August 2011,
<https://www.rfc-editor.org/info/rfc6349>.
[RFC7285] Alimi, R., Ed., Penno, R., Ed., Yang, Y., Ed., Kiesel, S.,
Previdi, S., Roome, W., Shalunov, S., and R. Woundy,
"Application-Layer Traffic Optimization (ALTO) Protocol",
RFC 7285, DOI 10.17487/RFC7285, September 2014,
<https://www.rfc-editor.org/info/rfc7285>.
[RFC7471] Giacalone, S., Ward, D., Drake, J., Atlas, A., and S.
Previdi, "OSPF Traffic Engineering (TE) Metric
Extensions", RFC 7471, DOI 10.17487/RFC7471, March 2015,
<https://www.rfc-editor.org/info/rfc7471>.
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[RFC7679] Almes, G., Kalidindi, S., Zekauskas, M., and A. Morton,
Ed., "A One-Way Delay Metric for IP Performance Metrics
(IPPM)", STD 81, RFC 7679, DOI 10.17487/RFC7679, January
2016, <https://www.rfc-editor.org/info/rfc7679>.
[RFC7680] Almes, G., Kalidindi, S., Zekauskas, M., and A. Morton,
Ed., "A One-Way Loss Metric for IP Performance Metrics
(IPPM)", STD 82, RFC 7680, DOI 10.17487/RFC7680, January
2016, <https://www.rfc-editor.org/info/rfc7680>.
[RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and
S. Ray, "North-Bound Distribution of Link-State and
Traffic Engineering (TE) Information Using BGP", RFC 7752,
DOI 10.17487/RFC7752, March 2016,
<https://www.rfc-editor.org/info/rfc7752>.
[RFC7810] Previdi, S., Ed., Giacalone, S., Ward, D., Drake, J., and
Q. Wu, "IS-IS Traffic Engineering (TE) Metric Extensions",
RFC 7810, DOI 10.17487/RFC7810, May 2016,
<https://www.rfc-editor.org/info/rfc7810>.
12.2. Informative References
[I-D.ietf-alto-deployments]
Stiemerling, M., Kiesel, S., Scharf, M., Seidel, H., and
S. Previdi, "ALTO Deployment Considerations", draft-ietf-
alto-deployments-16 (work in progress), July 2016.
[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: bill.wu@huawei.com
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Y. Richard Yang
Yale University
51 Prospect St
New Haven, CT 06520
USA
Email: yry@cs.yale.edu
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
Nokia Bell Labs
Route de Villejust
Nozay 91460
FRANCE
Email: sabine.randriamasy@nokia-bell-labs.com
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