draft-ietf-alto-unified-props-new-00.txt   draft-ietf-alto-unified-props-new-01.txt 
ALTO WG W. Roome ALTO WG W. Roome
Internet-Draft Nokia Bell Labs Internet-Draft Nokia Bell Labs
Intended status: Standards Track R. Yang Intended status: Standards Track S. Chen
Expires: January 21, 2018 Yale University Expires: June 20, 2018 X. Wang
July 20, 2017 Tongji University
Y. Yang
Yale University
J. Zhang
Tongji University
December 17, 2017
Extensible Property Maps for the ALTO Protocol Extensible Property Maps for the ALTO Protocol
draft-ietf-alto-unified-props-new-00 draft-ietf-alto-unified-props-new-01
Abstract Abstract
This document extends the Application-Layer Traffic Optimization This document extends the Application-Layer Traffic Optimization
(ALTO) Protocol [RFC7285] by generalizing the concept of "endpoint (ALTO) Protocol [RFC7285] by generalizing the concept of "endpoint
properties" to other entity domains, and by presenting those properties" to other entity domains, and by presenting those
properties as maps, similar to the network and cost maps in ALTO. properties as maps, similar to the network and cost maps in ALTO.
Requirements Language Requirements Language
skipping to change at page 1, line 40 skipping to change at page 1, line 45
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
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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 January 21, 2018. This Internet-Draft will expire on June 20, 2018.
Copyright Notice Copyright Notice
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Definitions and Concepts . . . . . . . . . . . . . . . . . . 4 2. Definitions and Concepts . . . . . . . . . . . . . . . . . . 4
2.1. Entities . . . . . . . . . . . . . . . . . . . . . . . . 4 2.1. Entity . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2. Domains . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.2. Domain . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.3. Entity Addresses . . . . . . . . . . . . . . . . . . . . 4 2.3. Domain Name . . . . . . . . . . . . . . . . . . . . . . . 5
2.4. Domain Names . . . . . . . . . . . . . . . . . . . . . . 5 2.4. Entity Address . . . . . . . . . . . . . . . . . . . . . 5
2.5. Property Names . . . . . . . . . . . . . . . . . . . . . 5 2.5. Property Name . . . . . . . . . . . . . . . . . . . . . . 5
2.6. Relationship to Network Maps . . . . . . . . . . . . . . 6 2.6. Hierarchy and Inheritance . . . . . . . . . . . . . . . . 6
2.7. Relationship with Other ALTO Resources . . . . . . . . . 6
3. Entity Domains . . . . . . . . . . . . . . . . . . . . . . . 7 3. Entity Domains . . . . . . . . . . . . . . . . . . . . . . . 7
3.1. Internet Address Domains . . . . . . . . . . . . . . . . 7 3.1. Internet Address Domains . . . . . . . . . . . . . . . . 7
3.1.1. IPV4 Domain . . . . . . . . . . . . . . . . . . . . . 7 3.1.1. IPv4 Domain . . . . . . . . . . . . . . . . . . . . . 7
3.1.2. IPV6 Domain . . . . . . . . . . . . . . . . . . . . . 7 3.1.2. IPv6 Domain . . . . . . . . . . . . . . . . . . . . . 8
3.1.3. Heirarchy And Inheritance of ipv4/ipv6 Domains . . . 8 3.1.3. Hierarchy and Inheritance of ipv4/ipv6 Domains . . . 8
3.1.4. Relationship To Network Maps . . . . . . . . . . . . 9 3.1.4. Relationship to Network Maps . . . . . . . . . . . . 9
3.2. PID Domain . . . . . . . . . . . . . . . . . . . . . . . 9 3.2. PID Domain . . . . . . . . . . . . . . . . . . . . . . . 10
3.2.1. Domain Name . . . . . . . . . . . . . . . . . . . . . 9 3.2.1. Domain Name . . . . . . . . . . . . . . . . . . . . . 10
3.2.2. Domain-Specific Entity Addresses . . . . . . . . . . 9 3.2.2. Domain-Specific Entity Addresses . . . . . . . . . . 10
3.2.3. Heirarchy And Inheritance . . . . . . . . . . . . . . 9 3.2.3. Hierarchy and Inheritance . . . . . . . . . . . . . . 10
3.2.4. Relationship To Internet Addresses Domains . . . . . 9 3.2.4. Relationship To Internet Addresses Domains . . . . . 10
3.3. Internet Address Properties vs. PID Properties . . . . . 10 3.3. Internet Address Properties vs. PID Properties . . . . . 10
3.4. ANE Domain . . . . . . . . . . . . . . . . . . . . . . . 10 3.4. ANE Domain . . . . . . . . . . . . . . . . . . . . . . . 11
3.4.1. Domain Name . . . . . . . . . . . . . . . . . . . . . 10 3.4.1. Domain Name . . . . . . . . . . . . . . . . . . . . . 11
3.4.2. Domain-Specific Entity Addresses . . . . . . . . . . 10 3.4.2. Domain-Specific Entity Addresses . . . . . . . . . . 11
3.4.3. Heirarchy And Inheritance . . . . . . . . . . . . . . 10 3.4.3. Hierarchy and Inheritance . . . . . . . . . . . . . . 11
4. Property Map Resource . . . . . . . . . . . . . . . . . . . . 10 4. Property Map Resource . . . . . . . . . . . . . . . . . . . . 11
4.1. Media Type . . . . . . . . . . . . . . . . . . . . . . . 11 4.1. Media Type . . . . . . . . . . . . . . . . . . . . . . . 11
4.2. HTTP Method . . . . . . . . . . . . . . . . . . . . . . . 11 4.2. HTTP Method . . . . . . . . . . . . . . . . . . . . . . . 11
4.3. Accept Input Parameters . . . . . . . . . . . . . . . . . 11 4.3. Accept Input Parameters . . . . . . . . . . . . . . . . . 11
4.4. Capabilities . . . . . . . . . . . . . . . . . . . . . . 11 4.4. Capabilities . . . . . . . . . . . . . . . . . . . . . . 12
4.5. Uses . . . . . . . . . . . . . . . . . . . . . . . . . . 11 4.5. Uses . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.6. Response . . . . . . . . . . . . . . . . . . . . . . . . 12 4.6. Response . . . . . . . . . . . . . . . . . . . . . . . . 12
5. Filtered Property Map Resource . . . . . . . . . . . . . . . 13 5. Filtered Property Map Resource . . . . . . . . . . . . . . . 13
5.1. Media Type . . . . . . . . . . . . . . . . . . . . . . . 13 5.1. Media Type . . . . . . . . . . . . . . . . . . . . . . . 13
5.2. HTTP Method . . . . . . . . . . . . . . . . . . . . . . . 13 5.2. HTTP Method . . . . . . . . . . . . . . . . . . . . . . . 13
5.3. Accept Input Parameters . . . . . . . . . . . . . . . . . 13 5.3. Accept Input Parameters . . . . . . . . . . . . . . . . . 13
5.4. Capabilities . . . . . . . . . . . . . . . . . . . . . . 14 5.4. Capabilities . . . . . . . . . . . . . . . . . . . . . . 14
5.5. Uses . . . . . . . . . . . . . . . . . . . . . . . . . . 14 5.5. Uses . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.6. Response . . . . . . . . . . . . . . . . . . . . . . . . 14 5.6. Response . . . . . . . . . . . . . . . . . . . . . . . . 14
6. Impact On Legacy Servers And Clients . . . . . . . . . . . . 14 6. Impact on Legacy ALTO Servers and ALTO Clients . . . . . . . 14
6.1. Impact on Endpoint Property Service . . . . . . . . . . . 14 6.1. Impact on Endpoint Property Service . . . . . . . . . . . 14
6.2. Impact on Resource-Specific Properties . . . . . . . . . 14 6.2. Impact on Resource-Specific Properties . . . . . . . . . 15
6.3. Impact on the "pid" Property . . . . . . . . . . . . . . 15 6.3. Impact on the "pid" Property . . . . . . . . . . . . . . 15
6.4. Impact on Other Properties . . . . . . . . . . . . . . . 15 6.4. Impact on Other Properties . . . . . . . . . . . . . . . 16
7. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 15 7. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 16
7.1. Network Map . . . . . . . . . . . . . . . . . . . . . . . 15 7.1. Network Map . . . . . . . . . . . . . . . . . . . . . . . 16
7.2. Property Definitions . . . . . . . . . . . . . . . . . . 16 7.2. Property Definitions . . . . . . . . . . . . . . . . . . 16
7.3. Information Resource Directory (IRD) . . . . . . . . . . 16 7.3. Information Resource Directory (IRD) . . . . . . . . . . 16
7.4. Property Map Example . . . . . . . . . . . . . . . . . . 18 7.4. Property Map Example . . . . . . . . . . . . . . . . . . 18
7.5. Filtered Property Map Example #1 . . . . . . . . . . . . 18 7.5. Filtered Property Map Example #1 . . . . . . . . . . . . 19
7.6. Filtered Property Map Example #2 . . . . . . . . . . . . 19 7.6. Filtered Property Map Example #2 . . . . . . . . . . . . 20
7.7. Filtered Property Map Example #3 . . . . . . . . . . . . 20 7.7. Filtered Property Map Example #3 . . . . . . . . . . . . 21
8. Security Considerations . . . . . . . . . . . . . . . . . . . 21 7.8. Filtered Property Map Example #4 . . . . . . . . . . . . 22
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 22 8. Security Considerations . . . . . . . . . . . . . . . . . . . 23
9.1. application/alto-* Media Types . . . . . . . . . . . . . 22 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 24
9.2. ALTO Entity Domain Registry . . . . . . . . . . . . . . . 23 9.1. application/alto-* Media Types . . . . . . . . . . . . . 24
9.3. ALTO Endpoint Property Type Registry . . . . . . . . . . 24 9.2. ALTO Entity Domain Registry . . . . . . . . . . . . . . . 25
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 25 9.3. ALTO Endpoint Property Type Registry . . . . . . . . . . 26
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 25 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 26
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 27
1. Introduction 1. Introduction
The ALTO protocol [RFC7285] introduced the concept of "properties" The ALTO protocol [RFC7285] introduced the concept of "properties"
attached to "endpoint addresses," and defined the Endpoint Property attached to "endpoint addresses", and defined the Endpoint Property
Service (EPS) to allow clients to retrieve those properties. While Service (EPS) to allow clients to retrieve those properties. While
useful, the EPS, as defined in RFC7285, has at least two limitations. useful, the EPS, as defined in RFC7285, has at least two limitations.
First, it only allows properties to be associated with a particular First, it only allows properties to be associated with a particular
domain of entities, namely individual IP addresses. It is reasonable domain of entities, namely individual IP addresses. It is reasonable
to think that collections of endpoints, as defined by CIDRs or PIDs, to think that collections of endpoints, as defined by CIDRs
may also have properties. Furthermore, recent proposals ([RFC4632]) or PIDs, may also have properties. Furthermore, a recent
([ID-draft-yang-alto-path-vector-04] and proposal ([I-D.ietf-alto-path-vector]) has suggested new classes of
[ID-draft-yang-alto-topology-06]) have suggested new classes of entities (ANE) with properties. The EPS cannot be extended to new
entities with properties. The EPS cannot be extended to new entity entity domains. Instead, new services, with new request and response
domains. Instead, new services, with new request and response
messages, would have to be defined for each new entity domain. messages, would have to be defined for each new entity domain.
Second, the EPS is only defined as a POST-mode service. Clients must Second, the EPS is only defined as a POST-mode service. Clients must
request the properties for an explicit set of addresses. By request the properties for an explicit set of addresses. By
contrast, [RFC7285] defines a GET-mode Cost Map resource which contrast, [RFC7285] defines a GET-mode Cost Map resource which
returns all available costs, so a client can get the full set of returns all available costs, so a client can get a full set of costs
costs once, and then lookup costs without querying the ALTO server. once, and then processes costs lookup without querying the ALTO
RFC7285 does not define an equivalent service for endpoint server. RFC7285 does not define an equivalent service for endpoint
properties. Granted, it is not be practical to enumerate the properties. And it is unlikely a property will be defined for every
properties for every possible Internet address. But it is unlikely a possible address. It is very likely that properties will only be
property will be defined for every possible address. It is very defined for a subset of addresses, and that subset would be small
likely that properties will only be defined for a subset of enough to enumerate. This is particularly true if blocks of
addresses, and that subset would be small enough to enumerate. This addresses with a common prefix (e.g., a CIDR) have the same value for
is particularly true if blocks of addresses with a common prefix a property. Furthermore, entities in other domains may very well be
(e.g., a CIDR) have the same value for a property. Furthermore, enumerable.
entities in other domains may very well be enumerable.
This document proposes a new approach to ALTO properties. This document proposes a new approach to retrieve ALTO properties.
Specifically, it defines two new resource types, namely Property Maps Specifically, it defines two new resource types, namely Property Maps
(see Section 4) and Filtered Property Maps (see Section 5). The (see Section 4) and Filtered Property Maps (see Section 5). The
former are GET-mode resources which return the property values for former are GET-mode resources which return the property values for
all entities in a domain, and are analogous the ALTO's Network Map all entities in a domain, and are analogous to the ALTO's Network
and Cost Map resources. The latter are POST-mode resources which Maps and Cost Maps. The latter are POST-mode resources which return
return the values for a set of properties and entities requested by the values for a set of properties and entities requested by the
the client, and are analogous to ALTO's Filtered Network Maps and client, and are analogous to the ALTO's Filtered Network Maps and
Filtered Cost Maps. Filtered Cost Maps.
Entity domains and property names are extensible, so that new domains Entity domains and property names are extensible. New domains can be
can be defined without revising the messages defined in this defined without revising the messages defined in this document, in
document, in the same way that new cost metrics and new endpoint the same way that new cost metrics and new endpoint properties can be
properties can be defined without revising the messages defined by defined without revising the messages defined by the ALTO protocol.
the ALTO protocol.
This proposal would subsume the Endpoint Property Service defined in This proposal would subsume the Endpoint Property Service defined in
RFC7285, although that service may be retained for legacy clients RFC7285, although that service may be retained for legacy clients
(see Section 6). (see Section 6).
2. Definitions and Concepts 2. Definitions and Concepts
2.1. Entities 2.1. Entity
An entity is an object with a (possibly empty) set of properties. An entity is an object with a (possibly empty) set of properties.
Every entity is in a domain, such as the IPv4 and IPv6 domains, and Every entity is in a domain, such as the IPv4 and IPv6 domains, and
has a unique address. has a unique address.
2.2. Domains 2.2. Domain
A domain is a family of entities. Two examples are the Internet A domain is a family of entities. Two examples are the Internet
address and PID domains (see Section 3.1 and Section 3.2) that this address and PID domain (see Section 3.1 and Section 3.2) that this
document will define. An additinoal example is the proposed domain document will define. An additional example is the proposed domain
of Abstract Network Elements associated with topology and routing, as of Abstract Network Elements associated with topology and routing, as
suggested by [ID-draft-yang-alto-path-vector-04]. suggested by [I-D.ietf-alto-path-vector].
2.3. Entity Addresses 2.3. Domain Name
Each domain has a unique name. A domain name MUST be no more than 32
characters, and MUST NOT contain characters other than US-ASCII
alphanumeric characters (U+0030-U+0039, U+0041-U+005A, and
U+0061-U+007A), hyphen ('-', U+002D), and low line ('_', U+005F).
For example, the names "ipv4" and "ipv6" identify objects in the
Internet address domain (Section 3.1).
The type DomainName is used in this document to denote a JSON string
with a domain name in this format.
Domain names MUST be registered with the IANA, and the format of the
entity addresses in that domain, as well as any hierarchical or
inheritance rules for those entities, MUST be specified at the same
time.
2.4. Entity Address
Each entity has a unique address of the format: Each entity has a unique address of the format:
domain-name : domain-specific-entity-address domain-name : domain-specific-entity-address
Examples from the IP domain include individual addresses such as Examples from the IP domain include individual addresses such as
"ipv4:192.0.2.14" and "ipv6:2001:db8::12", as well as address blocks "ipv4:192.0.2.14" and "ipv6:2001:db8::12", as well as address blocks
such as "ipv4:192.0.2.0/26" and "ipv6:2001:db8:1/48". such as "ipv4:192.0.2.0/26" and "ipv6:2001:db8::1/48".
The type EntityAddr denotes a JSON string with an entity address in The type EntityAddr is used in this document to denote a JSON string
this format. with an entity address in this format.
The format of the second part of an entity address depends on the The format of the second part of an entity address depends on the
domain, and must be specified when registering a new domain. domain, and MUST be specified when registering a new domain.
Addresses may be hierarchical, and properties may be inherited based Addresses MAY be hierarchical, and properties MAY be inherited based
on that hierarchy. Again, the rules defining any hierarchy or on that hierarchy. Again, the rules defining any hierarchy or
inheritance must be defined when the domain is registered. inheritance MUST be defined when the domain is registered.
Note that entity addresses may NOT have a unique textual Note that entity addresses MAY have different textual
representation, for a given domain. For example, the strings representations, for a given domain. For example, the strings
"ipv6:2001:db8::1" and "ipv6:2001:db8:0:0:0:0:0:1" refer to the same "ipv6:2001:db8::1" and "ipv6:2001:db8:0:0:0:0:0:1" refer to the same
entity. entity.
2.4. Domain Names 2.5. Property Name
Each domain has a unique name. A domain name MUST be no more than 32
characters, and MUST NOT contain characters other than US-ASCII
alphanumeric characters (U+0030-U+0039, U+0041-U+005A, and
U+0061-U+007A), hyphen ('-', U+002D), and low line ('_', U+005F).
For example, the names "ipv4" and "ipv6" identify objects in the
Internet address domain (Section 3.1).
The type DomainName denotes a JSON string with a domain name in this
format.
Domain names must be registered with the IANA, and the format of the
entity addresses in that domain, as well as any hierarchical or
inheritance rules for those entities, MUST be specified at the same
time.
2.5. Property Names
The space of property names associated with entities defined by this The space of property names associated with entities defined by this
document is the same as, and is shared with, the endpoint property document is the same as, and is shared with, the endpoint property
names defined by [RFC7285]. Thus entity property names are as names defined by [RFC7285]. Thus entity property names are as
defined in Section 10.8.2 of that document, and must be registered defined in Section 10.8.2 of that document, and must be registered
with the "ALTO Endpoint Property Type Registry" defined in with the "ALTO Endpoint Property Type Registry" defined in
Section 14.3 of that document. Section 9.3 of that document. The type PropertyName denotes a JSON
string with a property name in this format.
The type PropertyName denotes a JSON string with a property name in
this format.
This document defines uniform property names specified in a single This document defines uniform property names specified in a single
property name sapce rather than being scoped by a specific domain, property name sapce rather than being scoped by a specific domain,
although some properties may only be applicable for particular although some properties may only be applicable for particular
domains. This design decision is to enforce a design so that similar domains. This design decision is to enforce a design so that similar
properties are named similarly. The interpretation of the value of a properties are named similarly. The interpretation of the value of a
property, howerver, may depend on the domain. For example, suppose property, howerver, may depend on the domain. For example, suppose
the "geo-location" property is defined as the coordinates of a point, the "geo-location" property is defined as the coordinates of a point,
encoded as (say) "latitude longitude [altitude]." When applied to an encoded as (say) "latitude longitude [altitude]." When applied to an
entity that represents a specific host computer, such as an Internet entity that represents a specific host computer, such as an Internet
address, the property defines the host's location. When applied to address, the property defines the host's location. When applied to
an entity that represents a set of computers, such as a CIDR, the an entity that represents a set of computers, such as a CIDR, the
property would be the location of the center of that set. If it is property would be the location of the center of that set. If it is
necessary to represent the bounding box of a set of hosts, another necessary to represent the bounding box of a set of hosts, another
property, such as "geo-region", should be defined. property, such as "geo-region", should be defined.
2.6. Relationship to Network Maps 2.6. Hierarchy and Inheritance
[RFC7285] recognizes that some properties may be specific to an ALTO Entities in a given domain MAY form hierarchy based on entity
resource, such as a network map. Accordingly [RFC7285] defines the address. Each domain MUST define its own hierarchy and inheritance
concept of "resource-specific endpoint properties" (Section 10.8.1), rules when registered. The hierarchy and inheritance rule makes it
and indicates that dependency by prefixing the property name with the possible for an entity to inherit a property value from another
ID of the resource on which it depends. That document defines one entity in the same domain. If and only if the property of an entity
resource-specific property, namely the "pid" property, whose value is is undefined, the hierarchy and inheritance rules are applied.
the name of the PID containing that endpoint in the associated
network map. 2.7. Relationship with Other ALTO Resources
[RFC7285] recognizes that some properties MAY be specific to another
ALTO resource, such as a network map. Accordingly [RFC7285] defines
the concept of "resource-specific endpoint properties"
(Section 10.8.1), and indicates that dependency by prefixing the
property name with the ID of the resource on which it depends. That
document defines one resource-specific property, namely the "pid"
property, whose value is the name of the PID containing that endpoint
in the associated network map.
This document takes a different approach. Instead of defining the This document takes a different approach. Instead of defining the
dependency by qualifying the property name, this document attaches dependency by qualifying the property name, this document attaches
the dependency to the property map as a whole. Thus all properties the dependency to the domains. Thus all properties of a specific
in a given property map depend on the same resource. Furthermore, domain depend on the same resource, the properties of another domain
entity addresses may depend on a network map (for example, the may depend on another resource. For example, entities in the PID
Abstract Network Elements suggested by domain depends on a network map, entities in the ANE domain depends
[ID-draft-yang-alto-path-vector-04]). Associating the dependency on a cost map or a endpoint cost map.
with the property map handles any entity address dependencies as
well.
The "uses" field in an IRD entry defines the dependencies of a The "uses" field in an IRD entry defines the dependencies of a
property map resource, and the "dependent-vtags" field in a property property map resource, and the "dependent-vtags" field in a property
map response defines the dependencies of that map. These fields are map response defines the dependencies of that map. These fields are
defined in Sections 9.1.5 and 11.1 of [RFC7285], respectively. defined in Sections 9.1.5 and 11.1 of [RFC7285], respectively.
This is similar to how RFC7285 handles dependencies between cost maps The "uses" field in an IRD entry MUST NOT include two dependent
and network maps. Recall that cost maps present the costs between resources with the same media type. This is similar to how RFC7285
PIDs, and PID names depend on a network map. If an ALTO server handles dependencies between cost maps and network maps. Recall that
provides the "routingcost" metric for the network maps "net1" and cost maps present the costs between PIDs, and PID names depend on a
"net2", then the server defines two separate cost maps, one for network map. If an ALTO server provides the "routingcost" metric for
"net1" and the other for "net2". the network maps "net1" and "net2", then the server defines two
separate cost maps, one for "net1" and the other for "net2".
According to [RFC7285], an ALTO server with two network maps, with According to [RFC7285], a legacy ALTO server with two network maps,
resource IDs "net1" and "net2", could offer a single Endpoint with resource IDs "net1" and "net2", could offer a single Endpoint
Property Service for the two properties "net1.pid" and "net2.pid". Property Service for the two properties "net1.pid" and "net2.pid".
An ALTO server which supports the extensions defined in this An ALTO server which supports the extensions defined in this
document, would, instead, offer two different property maps for the document, would, instead, offer two different Property Maps for the
"pid" property, one depending on "net1", the other on "net2". "pid" property, one depending on "net1", the other on "net2".
3. Entity Domains 3. Entity Domains
This document defines the following entity domains. For the This document defines the following entity domains. For the
definition of each domain, it includes the following template: domain definition of each domain, it includes the following template: domain
name, domain-specific addresses, and heirarchy and inheritance name, domain-specific addresses, and hierarchy and inheritance
semantics. semantics.
3.1. Internet Address Domains 3.1. Internet Address Domains
The document defines two domains (IPv4 and IPv6) for Internet The document defines two domains (IPv4 and IPv6) for Internet
addresses. Both domains include individual addresses and blocks of addresses. Both domains include individual addresses and blocks of
addresses. addresses.
3.1.1. IPV4 Domain 3.1.1. IPv4 Domain
3.1.1.1. Domain Name 3.1.1.1. Domain Name
ipv4 ipv4
3.1.1.2. Domain-Specific Entity Addresses 3.1.1.2. Domain-Specific Entity Addresses
Individual addresses are strings as specified by the IPv4Addresses Individual addresses are strings as specified by the IPv4Addresses
rule of Section 3.2.2 of [RFC3986]. Blocks of addresses are prefix- rule of Section 3.2.2 of [RFC3986]. Blocks of addresses are prefix-
match strings as specified in Section 3.1 of [RFC4632]. match strings as specified in Section 3.1 of [RFC4632]. For the
purpose of defining properties, an individual Internet address and
For the purpose of defining properties, an individual Internet the corresponding full-length prefix are considered aliases for the
address and the corresponding full-length prefix are considered same entity. Thus "ipv4:192.0.2.0" and "ipv4:192.0.2.0/32" are
aliases for the same entity. Thus "ipv4:192.0.2.0" and equivalent.
"ipv4:192.0.2.0/32" are equivalent.
3.1.2. IPV6 Domain 3.1.2. IPv6 Domain
3.1.2.1. Domain Name 3.1.2.1. Domain Name
ipv6 ipv6
3.1.2.2. Domain-Specific Entity Addresses 3.1.2.2. Domain-Specific Entity Addresses
Individual addresses are strings as specified by Section 4 of Individual addresses are strings as specified by Section 4 of
[RFC5952]. Blocks of addresses are prefix-match strings as specified [RFC5952]. Blocks of addresses are prefix-match strings as specified
in Section 7 of [RFC5952]. in Section 7 of [RFC5952]. For the purpose of defining properties,
an individual Internet address and the corresponding 128-bit prefix
For the purpose of defining properties, an individual Internet are considered aliases for the same entity. That is,
address and the corresponding 128-bit prefix are considered aliases "ipv6:2001:db8::1" and "ipv6:2001:db8::1/128" are equivalent, and
for the same entity. That is, "ipv6:2001:db8::1" and have the same set of properties.
"ipv6:2001:db8::1/128" are equivalent, and have the same set of
properties.
3.1.3. Heirarchy And Inheritance of ipv4/ipv6 Domains 3.1.3. Hierarchy and Inheritance of ipv4/ipv6 Domains
Both domains allow property values to be inherited. Specifically, if Both domains allow property values to be inherited. Specifically, if
a property P is not defined for a specific Internet address IP, but P a property P is not defined for a specific Internet address I, but P
is defined for some block C which prefix-matches IP, then the address is defined for some block C which prefix-matches I, then the address
IP inherits the value of P defined for block C. If more than one I inherits the value of P defined for block C. If more than one such
such block defines a value for P, IP inherits the value of P in the block defines a value for P, I inherits the value of P in the block
block with the longest prefix. It is important to notice that this with the longest prefix. It is important to notice that this longest
longest prefix rule will ensure no multiple inheritance, and hence no prefix rule will ensure no multiple inheritance, and hence no
ambiguity. ambiguity.
Address blocks can also inherit properties: if property P is not Address blocks can also inherit properties: if property P is not
defined for a block C, but is defined for some block C' prefix- defined for a block C, but is defined for some block C' prefix-
matches C, and C' has a shorter mask than C, then block C inherits matches C, and C' has a shorter mask than C, then block C inherits
the property from C'. If there are several such blocks C', C the property from C'. If there are several such blocks C', C
inherits from the block with the longest prefix. inherits from the block with the longest prefix.
As an example, suppose that a server defines the property P for the As an example, suppose that a server defines the property P for the
following entities: following entities:
ipv4:192.0.2.0/26: P=v1 ipv4:192.0.2.0/26: P=v1
ipv4:192.0.2.0/28: P=v2 ipv4:192.0.2.0/28: P=v2
ipv4:192.0.2.0/30: P=v3 ipv4:192.0.2.0/30: P=v3
ipv4:192.0.2.0: P=v4 ipv4:192.0.2.0: P=v4
Defined Property Values Figure 1: Defined Property Values.
Then the following entities have the indicated values: Then the following entities have the indicated values:
ipv4:192.0.2.0: P=v4 ipv4:192.0.2.0: P=v4
ipv4:192.0.2.1: P=v3 ipv4:192.0.2.1: P=v3
ipv4:192.0.2.16: P=v1 ipv4:192.0.2.16: P=v1
ipv4:192.0.2.32: P=v1 ipv4:192.0.2.32: P=v1
ipv4:192.0.2.64: (not defined) ipv4:192.0.2.64: (not defined)
ipv4:192.0.2.0/32: P=v4 ipv4:192.0.2.0/32: P=v4
ipv4:192.0.2.0/31: P=v3 ipv4:192.0.2.0/31: P=v3
ipv4:192.0.2.0/29: P=v2 ipv4:192.0.2.0/29: P=v2
ipv4:192.0.2.0/27: P=v1 ipv4:192.0.2.0/27: P=v1
ipv4:192.0.2.0/25: (not defined) ipv4:192.0.2.0/25: (not defined)
Inherited Property Values Figure 2: Inherited Property Values.
3.1.4. Relationship To Network Maps An ALTO Server MAY explicitly indicate a property as not having a
value for a particular entity. That is, a server MAY say that
property A of entity X is "defined to have no value", instead of
"undefined". To indicate "no value", a server MAY perform different
behaviours:
An Internet address domain may or may not be associated with an ALTO o If that entity would inherit a value for that property, then the
network map resource. Logically, there is a map of Internet address ALTO server MUST return a "null" value for that property. In this
entities to property values for each network map defined by the ALTO case, the ALTO client MUST recognize a "null" value as "no value"
server, plus an additional property map for Internet address entities and "do not apply the inheritance rules for this property."
which are not associated with a network map. So, if there is n
network maps, the server can provide n+1 maps of Internet address o If the entity would not inherit a value, then the ALTO server MAY
entities to property values.So, if there is n network maps, the return "null" or just omit the property. In this case, the ALTO
server may provide n+1 maps of Internet address entities to property client cannot infer the value for this property of this entity
values. These maps are separate from each other. The prefixes in from the Inheritance rules. So the client MUST interpret this
the property map do not have to correspond to the prefixes defining property has "no value".
the network map's PIDs. For example, the property map for a network
map may assign properties to "ipv4:192.0.2.0/24" even if that prefix If the ALTO Server does not define any properties for an entity, then
is not associated with any PID in the network map. the server MAY omit that entity from the response.
3.1.4. Relationship to Network Maps
An Internet address domain MAY be associated with an ALTO network map
resource. Logically, there is a map of Internet address entities to
property values for each network map defined by the ALTO server, plus
an additional property map for Internet address entities which are
not associated with a network map. So, if there is n network maps,
the server can provide n+1 maps of Internet address entities to
property values. These maps are separate from each other. The
prefixes in the property map do not have to correspond to the
prefixes defining the network map's PIDs. For example, the property
map for a network map MAY assign properties to "ipv4:192.0.2.0/24"
even if that prefix is not associated with any PID in the network
map.
3.2. PID Domain 3.2. PID Domain
The PID domain associates property values with the PIDs in a network The PID domain associates property values with the PIDs in a network
map. Accordingly, this domain always depends on a network map. map. Accordingly, this domain always depends on a network map.
3.2.1. Domain Name 3.2.1. Domain Name
pid pid
3.2.2. Domain-Specific Entity Addresses 3.2.2. Domain-Specific Entity Addresses
The entity addresses are the PID names of the associated network map. The entity addresses are the PID names of the associated network map.
3.2.3. Heirarchy And Inheritance 3.2.3. Hierarchy and Inheritance
There is no hierarchy or inheritance for properties associated with There is no hierarchy or inheritance for properties associated with
PIDs. PIDs.
3.2.4. Relationship To Internet Addresses Domains 3.2.4. Relationship To Internet Addresses Domains
The PID domain and the Internet address domains are completely The PID domain and the Internet address domains are completely
independent; the properties associated with a PID have no relation to independent; the properties associated with a PID have no relation to
the properties associated with the prefixes or endpoint addresses in the properties associated with the prefixes or endpoint addresses in
that PID. An ALTO server MAY choose to assign some or all properties that PID. An ALTO server MAY choose to assign some or all properties
of a PID to the prefixes in that PID, but is not required to do so. of a PID to the prefixes in that PID.
For example, suppose "PID1" consists of the prefix For example, suppose "PID1" consists of the prefix
"ipv4:192.0.2.0/24", and has the property "P" with value "v1". The "ipv4:192.0.2.0/24", and has the property "P" with value "v1". The
Internet address entities "ipv4:192.0.2.0" and "ipv4:192.0.2.0/24", Internet address entities "ipv4:192.0.2.0" and "ipv4:192.0.2.0/24",
in the IPv4 domain may or may not have a value for the property "P", in the IPv4 domain MAY have a value for the property "P", and if they
and if they do, it is not necessarily "v1". do, it is not necessarily "v1".
3.3. Internet Address Properties vs. PID Properties 3.3. Internet Address Properties vs. PID Properties
Because the Internet address and PID domains are completely separate, Because the Internet address and PID domains are completely separate,
the question may arise as to which domain is best for a property. In the question may arise as to which domain is best for a property. In
general, the Internet address domain is best for properties that are general, the Internet address domain is RECOMMENDED for properties
closely related to the Internet address, or are associated with, and that are closely related to the Internet address, or are associated
inherited through, blocks of addresses. with, and inherited through, blocks of addresses.
The PID domain is best for properties that arise from the definition The PID domain is RECOMMENDED for properties that arise from the
of the PID, rather than from the Internet address prefixes in that definition of the PID, rather than from the Internet address prefixes
PID. in that PID.
For example, because Internet addresses are allocated to service For example, because Internet addresses are allocated to service
providers by blocks of prefixes, an "ISP" property would be best providers by blocks of prefixes, an "ISP" property would be best
associated with the Internet address domain. On the other hand, a associated with the Internet address domain. On the other hand, a
property that explains why a PID was formed, or how it relates the a property that explains why a PID was formed, or how it relates the a
provider's network, would best be associated with the PID domain. provider's network, would best be associated with the PID domain.
3.4. ANE Domain 3.4. ANE Domain
3.4.1. Domain Name 3.4.1. Domain Name
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The entity address of ane domain is encoded as a JSON string. The The entity address of ane domain is encoded as a JSON string. The
string MUST be no more than 64 characters, and it MUST NOT contain string MUST be no more than 64 characters, and it MUST NOT contain
characters other than US-ASCII alphanumeric characters characters other than US-ASCII alphanumeric characters
(U+0030-U+0039, U+0041-U+005A, and U+0061-U+007A), the hyphen ('-', (U+0030-U+0039, U+0041-U+005A, and U+0061-U+007A), the hyphen ('-',
U+002D), the colon (':', U+003A), the at sign ('@', code point U+002D), the colon (':', U+003A), the at sign ('@', code point
U+0040), the low line ('_', U+005F), or the '.' separator (U+002E). U+0040), the low line ('_', U+005F), or the '.' separator (U+002E).
The '.' separator is reserved for future use and MUST NOT be used The '.' separator is reserved for future use and MUST NOT be used
unless specifically indicated in this document, or an extension unless specifically indicated in this document, or an extension
document. document.
3.4.3. Heirarchy And Inheritance 3.4.3. Hierarchy and Inheritance
There is no hierarchy or inheritance for properties associated with There is no hierarchy or inheritance for properties associated with
ANEs. ANEs.
4. Property Map Resource 4. Property Map Resource
A Property Map returns the properties defined for all entities in one A Property Map returns the properties defined for all entities in one
or more domains. or more domains.
Section 7.4 gives an example of a property map request and its Section 7.4 gives an example of a property map request and its
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The capabilities are defined by an object of type The capabilities are defined by an object of type
PropertyMapCapabilities: PropertyMapCapabilities:
object { object {
DomainName domain-types<1..*>; DomainName domain-types<1..*>;
PropertyName prop-types<1..*>; PropertyName prop-types<1..*>;
} PropertyMapCapabilities; } PropertyMapCapabilities;
where "domain-types" is an array with the domains of the entities in where "domain-types" is an array with the domains of the entities in
this property map, and "prop-types" is an array with the names of the this property map, and "prop-types" is an array with the names of the
properties returned for entities in those domains. TODO: discuss properties returned for entities in those domains.
semantics and requirements of multiple domains.
If the server declares multiple domain-types and multiple prop-types
in the capability, each prop-type MUST be supported in each domain in
the "capabilities" field. In other words, if a prop-type is NOT
supported in a particular domain, the property map MUST be divided
into several maps.
4.5. Uses 4.5. Uses
An array with the resource ID(s) of resource(s) with which the An array with the resource ID(s) of resource(s) with which the
domains in this map are associated. In most cases, this array will domains in this map are associated. In most cases, this array will
have at most one ID, for example, for a network map resource. TODO: have at most one ID, for example, for a network map resource.
discuss semantics and requirements of multiple resources. However, However, the "uses" field MUST NOT contain two resources of the same
the "uses" field MUST NOT contain two resources of the same resource resource type. For example, if a property map depends on network map
type. For example, if a property map depends on network map
resource, the "uses" field MUST include exactly one network map resource, the "uses" field MUST include exactly one network map
resource. resource.
4.6. Response 4.6. Response
If the domains in this property map depend on other resources, the If the domains in this property map depend on other resources, the
"dependent-vtags" field in the "meta" field of the response MUST be "dependent-vtags" field in the "meta" field of the response MUST be
an array that includes the version tags of those resources. an array that includes the version tags of those resources. The data
component of a Property Map response is named "property-map", which
The data component of a Property Map response is named "property- is a JSON object of type PropertyMapData, where:
map", which is a JSON object of type PropertyMapData, where:
object { object {
PropertyMapData property-map; PropertyMapData property-map;
} InfoResourceProperties : ResponseEntityBase; } InfoResourceProperties : ResponseEntityBase;
object-map { object-map {
EntityAddr -> EntityProps; EntityAddr -> EntityProps;
} PropertyMapData; } PropertyMapData;
object { object {
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implementation is using an extension to this document that indicates implementation is using an extension to this document that indicates
when and how property values of other data types are signaled. when and how property values of other data types are signaled.
For each entity in the Property Map, the ALTO Server returns the For each entity in the Property Map, the ALTO Server returns the
value defined for each of the properties specified in this resource's value defined for each of the properties specified in this resource's
"capabilities" list. For efficiency, the ALTO Server SHOULD omit "capabilities" list. For efficiency, the ALTO Server SHOULD omit
property values that are inherited rather than explicitly defined; if property values that are inherited rather than explicitly defined; if
a client needs inherited values, the client SHOULD use the domain's a client needs inherited values, the client SHOULD use the domain's
inheritance rules to deduce those values. inheritance rules to deduce those values.
An ALTO Server MAY explicitly define a property as not having a value
for a particular entity. That is, a server may say that a property
is "defined to have no value", as opposed to the property being
"undefined". If the property for an entity is defined to have no
value, the server MUST set the property value to be a JSON null
value.
If the ALTO Server does not define any properties for an entity, then
the server MAY omit that entity from the response.
5. Filtered Property Map Resource 5. Filtered Property Map Resource
A Filtered Property Map returns the values of a set of properties for A Filtered Property Map returns the values of a set of properties for
a set of entities selected by the client. a set of entities selected by the client.
Section 7.5, Section 7.6 and Section 7.7 give examples of filtered Section 7.5, Section 7.6 and Section 7.7 give examples of filtered
property map requests and responses. property map requests and responses.
5.1. Media Type 5.1. Media Type
The media type of an ALTO Property Map resource is "application/alto- The media type of an ALTO Property Map resource is "application/alto-
propmap+json". propmap+json".
5.2. HTTP Method 5.2. HTTP Method
An ALTO Property Map resource is requested using the HTTP POST An ALTO Filtered Property Map resource is requested using the HTTP
method. POST method.
5.3. Accept Input Parameters 5.3. Accept Input Parameters
The input parameters for a Filtered Property Map request are supplied The input parameters for a Filtered Property Map request are supplied
in the entity body of the POST request. This document specifies the in the entity body of the POST request. This document specifies the
input parameters with a data format indicated by the media type input parameters with a data format indicated by the media type
"application/alto-propmapparams+json", which is a JSON object of type "application/alto-propmapparams+json", which is a JSON object of type
ReqFilteredPropertyMap: ReqFilteredPropertyMap:
object { object {
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The response is the same as for the property map (Section 4.6), The response is the same as for the property map (Section 4.6),
except that it only includes the entities and properties requested by except that it only includes the entities and properties requested by
the client. the client.
Also, the Filtered Property Map response MUST include all inherited Also, the Filtered Property Map response MUST include all inherited
property values for the specified entities (unlike the Full Property property values for the specified entities (unlike the Full Property
Map, the Filtered Property Map response does not include enough Map, the Filtered Property Map response does not include enough
information for the client to calculate the inherited values). information for the client to calculate the inherited values).
6. Impact On Legacy Servers And Clients 6. Impact on Legacy ALTO Servers and ALTO Clients
6.1. Impact on Endpoint Property Service 6.1. Impact on Endpoint Property Service
The property maps defined in this document provide the same The Property Maps defined in this document provide the same
functionality as the Endpoint Property Service (EPS) defined in functionality as the Endpoint Property Service (EPS) defined in
Section 11.4 of [RFC7285]. Accordingly, it is RECOMMENDED that the Section 11.4 of [RFC7285]. Accordingly, it is RECOMMENDED that the
EPS be deprecated in favor of property maps. However, ALTO servers EPS be deprecated in favor of Property Maps. However, ALTO servers
MAY provide an EPS for the benefit of legacy clients. MAY provide an EPS for the benefit of legacy clients.
6.2. Impact on Resource-Specific Properties 6.2. Impact on Resource-Specific Properties
Section 10.8 of [RFC7285] defines two categories of endpoint Section 10.8 of [RFC7285] defines two categories of endpoint
properties: "resource-specific" and "global". Resource-specific properties: "resource-specific" and "global". Resource-specific
property names are prefixed with the ID of the resource they depended property names are prefixed with the ID of the resource they depend
upon, while global property names have no such prefix. The property upon, while global property names have no such prefix. The property
map resources defined in this document do not distinguish between map resources defined in this document do not distinguish between
those two types of properties. Instead, if there is a dependency, it those two types of properties. Instead, if there is a dependency, it
is indicated by the "uses" capability of a property map, and is is indicated by the "uses" capability of a property map, and is
shared by all properties and entity domains in that map. shared by all properties and entity domains in that map.
Accordingly, it is RECOMMENDED that resource-specific endpoint Accordingly, it is RECOMMENDED that resource-specific endpoint
properties be deprecated, and no new resource-specific endpoint properties be deprecated, and no new resource-specific endpoint
properties be defined. properties be defined.
6.3. Impact on the "pid" Property 6.3. Impact on the "pid" Property
Section 7.1.1 of [RFC7285] defines the resource-specific endpoint Section 7.1.1 of [RFC7285] defines the resource-specific endpoint
property "pid", whose value is the name of the PID containing that property "pid", whose value is the name of the PID containing that
endpoint. For compatibility with legacy clients, an ALTO server endpoint. For compatibility with legacy clients, an ALTO server
which provides the "pid" property via the Endpoint Property Service which provides the "pid" property via the Endpoint Property Service
MUST use that definition, and that syntax, in the EPS resource. MUST use that definition, and that syntax, in the EPS resource.
However, when used with property maps, this document amends the However, when used with Property Maps, this document amends the
definition of the "pid" property as follows. definition of the "pid" property as follows.
First, the name of the property is simply "pid"; the name is not First, the name of the property is simply "pid"; the name is not
prefixed with the resource ID of a network map. The "uses" prefixed with the resource ID of a network map. The "uses"
capability of the property map resource indicates the associated capability of the property map resource indicates the associated
network map. This implies that a property map can only return the network map. This implies that a property map can only return the
"pid" property for one network map; if an ALTO server provides "pid" property for one network map; if an ALTO server provides
several network maps, it must provide a property map resource for several network maps, it MUST provide a property map resource for
each one. each one.
Second, a client MAY request the "pid" property for a block of Second, a client MAY request the "pid" property for a block of
addresses. An ALTO server determines the value of "pid" for an addresses. An ALTO server determines the value of "pid" for an
address block C as follows. Let CS be the set of all address blocks address block C as follows. Let CS be the set of all address blocks
in the network map. If C is in CS, then the value of "pid" is the in the network map. If C is in CS, then the value of "pid" is the
name of the PID associated with C. Otherwise, find the longest block name of the PID associated with C. Otherwise, find the longest block
C' in CS such that C' prefix-matches C, but is shorter than C. If C' in CS such that C' prefix-matches C, but is shorter than C. If
there is such a block C', the value of "pid" is the name of the PID there is such a block C', the value of "pid" is the name of the PID
associated with C'. If not, then "pid" has no value for block C. associated with C'. If not, then "pid" has no value for block C.
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defined properties. The only consideration is that properties can defined properties. The only consideration is that properties can
now be defined on blocks of addresses, rather than just individual now be defined on blocks of addresses, rather than just individual
addresses, which might change the semantics of a property. addresses, which might change the semantics of a property.
7. Examples 7. Examples
7.1. Network Map 7.1. Network Map
The examples in this section use a very simple default network map: The examples in this section use a very simple default network map:
defaultpid: ipv4:0.0.0.0/0 ipv6:::0/0 defaultpid: ipv4:0.0.0.0/0 ipv6:::0/0
pid1: ipv4:192.0.2.0/25 pid1: ipv4:192.0.2.0/25
pid2: ipv4:192.0.2.0/28 ipv4:192.0.2.16/28 pid2: ipv4:192.0.2.0/28 ipv4:192.0.2.16/28
Figure 1: Example Network Map Figure 3: Example Network Map
7.2. Property Definitions 7.2. Property Definitions
The examples in this section use four additional properties, "ISP", The examples in this section use four additional properties, "ISP",
"ASN", "country" and "state", with the following values: "ASN", "country" and "state", with the following values:
ISP ASN country state ISP ASN country state
ipv4:192.0.2.0/24: BitsRus - us - ipv4:192.0.2.0/24: BitsRus - us -
ipv4:192.0.2.0/28: - 12345 - NJ ipv4:192.0.2.0/28: - 12345 - NJ
ipv4:192.0.2.16/28: - 12345 - CT ipv4:192.0.2.16/28: - 12345 - CT
ipv4:192.0.2.0: - - - PA ipv4:192.0.2.0: - - - PA
Figure 2: Example Property Values Figure 4: Example Property Values
7.3. Information Resource Directory (IRD) 7.3. Information Resource Directory (IRD)
The following IRD defines the relevant resources of the ALTO server. The following IRD defines the relevant resources of the ALTO server.
It provides two Property Map resources, one for the "ISP" and "ASN" It provides two Property Map resources, one for the "ISP" and "ASN"
properties, and another for the "country" and "state" properties. properties, and another for the "country" and "state" properties.
The server could have provided a Property Map resource for all four The server could have provided a Property Map resource for all four
properties, but did not, presumably because the organization that properties, but did not, presumably because the organization that
runs the ALTO server believes any given client is not interested in runs the ALTO server believes any given client is not interested in
all four properties. all four properties.
The server provides two Filtered Property Maps. The first returns The server provides two Filtered Property Maps. The first returns
all four properties, and the second just returns the "pid" property all four properties, and the second just returns the "pid" property
for the default network map. for the default network map.
The Property Maps for the "ISP", "ASN", "country" and "state" The Filtered Property Maps for the "ISP", "ASN", "country" and
properties do not depend on the default network map (they do not have "state" properties do not depend on the default network map (it does
a "uses" capability), because the definitions of those properties do not have a "uses" capability), because the definitions of those
not depend on the default network map. The Filtered Property Map for properties do not depend on the default network map. The Filtered
the "pid" property does have a "uses" capability for the default Property Map for the "pid" property does have a "uses" capability for
network map, because that defines the values of the "pid" property. the default network map, because that defines the values of the "pid"
property.
Note that for legacy clients, the ALTO server provides an Endpoint Note that for legacy clients, the ALTO server provides an Endpoint
Property Service for the "pid" property for the default network map. Property Service for the "pid" property for the default network map.
"meta": { ... }, "meta": { ... },
"resources" : { "resources" : {
"default-network-map" : { "default-network-map" : {
"uri" : "http://alto.example.com/networkmap", "uri" : "http://alto.example.com/networkmap",
"media-type" : "application/alto-networkmap+json" "media-type" : "application/alto-networkmap+json"
},
.... property map resources ....
"country-state-property-map" : {
"uri" : "http://alto.example.com/propmap/full/inet-cs",
"media-type" : "application/alto-propmap+json",
"capabilities" : {
"domain-types": [ "ipv4", "ipv6" ],
"prop-types" : [ "country", "state" ]
}
},
"isp-asn-property-map" : {
"uri" : "http://alto.example.com/propmap/full/inet-ia",
"media-type" : "application/alto-propmap+json",
"capabilities" : {
"domain-types": [ "ipv4", "ipv6" ],
"prop-types" : [ "ISP", "ASN" ]
}
},
"iacs-property-map" : {
"uri" : "http://alto.example.com/propmap/lookup/inet-iacs",
"media-type" : "application/alto-propmap+json",
"accepts" : "application/alto-propmapparams+json",
"capabilities" : {
"domain-types": [ "ipv4", "ipv6" ],
"prop-types" : [ "ISP", "ASN", "country", "state" ]
}
},
"pid-property-map" : {
"uri" : "http://alto.example.com/propmap/lookup/pid",
"media-type" : "application/alto-propmap+json",
"accepts" : "application/alto-propmapparams+json",
"uses" : [ "default-network-map" ]
"capabilities" : {
"domain-types" : [ "ipv4", "ipv6" ],
"prop-types" : [ "pid" ]
}
},
"availbw-property-map" : {
"uri" : "http://alto.example.com/propmap/lookup/availbw",
"media-type" : "application/alto-propmap+json",
"accepts" : "application/alto-propmapparams+json",
"capabilities" : {
"domain-types" : [ "ane" ],
"prop-types" : [ "availbw", "delay" ]
}
},
"legacy-pid-property-map" : {
"uri" : "http://alto.example.com/legacy/eps-pid",
"media-type" : "application/alto-endpointprop+json",
"accepts" : "application/alto-endpointpropparams+json",
"capabilities" : {
"prop-types" : [ "default-network-map.pid" ]
}
}
}
}, Figure 5: Example IRD
.... property map resources ....
"country-state-property-map" : {
"uri" : "http://alto.example.com/propmap/full/inet-cs",
"media-type" : "application/alto-propmap+json",
"capabilities" : {
"domain-types": [ "ipv4", "ipv6" ],
"prop-types" : [ "country", "state" ]
}
},
"isp-asn-property-map" : {
"uri" : "http://alto.example.com/propmap/full/inet-ia",
"media-type" : "application/alto-propmap+json",
"capabilities" : {
"domain-types": [ "ipv4", "ipv6" ],
"prop-types" : [ "ISP", "ASN" ]
}
},
"iacs-property-map" : {
"uri" : "http://alto.example.com/propmap/lookup/inet-iacs",
"media-type" : "application/alto-propmap+json",
"accepts" : "application/alto-propmapparams+json",
"capabilities" : {
"domain-types": [ "ipv4", "ipv6" ],
"prop-types" : [ "ISP", "ASN", "country", "state" ]
}
},
"pid-property-map" : {
"uri" : "http://alto.example.com/propmap/lookup/pid",
"media-type" : "application/alto-propmap+json",
"accepts" : "application/alto-propmapparams+json",
"uses" : [ "default-network-map" ]
"capabilities" : {
"domain-types": [ "ipv4", "ipv6" ],
"prop-types" : [ "pid" ]
}
},
"legacy-pid-property" : {
"uri" : "http://alto.example.com/legacy/eps-pid",
"media-type" : "application/alto-endpointprop+json",
"accepts" : "application/alto-endpointpropparams+json",
"capabilities" : {
"prop-types" : [ "default-network-map.pid" ]
}
}
}
Example IRD
7.4. Property Map Example 7.4. Property Map Example
The following example uses the properties and IRD defined above to The following example uses the properties and IRD defined above to
retrieve a property map for entities with the "ISP" and "ASN" retrieve a property map for entities with the "ISP" and "ASN"
properties. Note that the response does not include the entity properties. Note that the response does not include the entity
"ipv4:192.0.2.0", because it does not have a value for either of "ipv4:192.0.2.0", because it does not have a value for either of
those properties. Also note that the entities "ipv4:192.0.2.0/28" those properties. Also note that the entities "ipv4:192.0.2.0/28"
and "ipv4:192.0.2.16/28" are refinements of "ipv4:192.0.2.0/24", and and "ipv4:192.0.2.16/28" are refinements of "ipv4:192.0.2.0/24", and
hence inherit its value for "ISP" property. But because that value hence inherit its value for "ISP" property. But because that value
skipping to change at page 19, line 36 skipping to change at page 20, line 37
{"ISP": "BitsRus", "ASN": "12345", "state": "NJ"}, {"ISP": "BitsRus", "ASN": "12345", "state": "NJ"},
"ipv4:192.0.2.17": "ipv4:192.0.2.17":
{"ISP": "BitsRus", "ASN": "12345", "state": "CT"} {"ISP": "BitsRus", "ASN": "12345", "state": "CT"}
} }
} }
7.6. Filtered Property Map Example #2 7.6. Filtered Property Map Example #2
The following example uses the Filtered Property Map resource to The following example uses the Filtered Property Map resource to
request the "ASN", "country" and "state" properties for several IPv4 request the "ASN", "country" and "state" properties for several IPv4
prefixes. Note that none of the returned property values were prefixes. Note that none of the returned property values is
explicitly defined; all values are derived by the inheritance rules explicitly defined; all values are derived by the inheritance rules
for Internet address entities. for Internet address entities.
Also note the "ASN" property has the value "12345" for both the Also note the "ASN" property has the value "12345" for both the
blocks "ipv4:192.0.2.0/28" and "ipv4:192.0.2.16/28", so every address blocks "ipv4:192.0.2.0/28" and "ipv4:192.0.2.16/28", so every address
in the block "ipv4:192.0.2.0/27" has that property value. However in the block "ipv4:192.0.2.0/27" has that property value. However
the block "ipv4:192.0.2.0/27" itself does not have a value for "ASN": the block "ipv4:192.0.2.0/27" itself does not have a value for "ASN":
address blocks cannot inherit properties from blocks with longer address blocks cannot inherit properties from blocks with longer
prefixes, even if every such block has the same value. prefixes, even if every such block has the same value.
skipping to change at page 20, line 38 skipping to change at page 21, line 39
} }
} }
7.7. Filtered Property Map Example #3 7.7. Filtered Property Map Example #3
The following example uses the Filtered Property Map resource to The following example uses the Filtered Property Map resource to
request the "pid" property for several IPv4 addresses and prefixes. request the "pid" property for several IPv4 addresses and prefixes.
Note that the value of "pid" for the prefix "ipv4:192.0.2.0/26" is Note that the value of "pid" for the prefix "ipv4:192.0.2.0/26" is
"pid1", even though all addresses in that block are in "pid2", "pid1", even though all addresses in that block are in "pid2",
because "ipv4:192.0.2.0/8" is the longest prefix in the network map because "ipv4:192.0.2.0/25" is the longest prefix in the network map
which prefix-matches "ipv4:192.0.2.0/26", and that prefix is in which prefix-matches "ipv4:192.0.2.0/26", and that prefix is in
"pid1". "pid1".
POST /propmap/lookup/pid HTTP/1.1 POST /propmap/lookup/pid HTTP/1.1
Host: alto.example.com Host: alto.example.com
Accept: application/alto-propmap+json,application/alto-error+json Accept: application/alto-propmap+json,application/alto-error+json
Content-Length: ### Content-Length: ###
Content-Type: application/alto-propmapparams+json Content-Type: application/alto-propmapparams+json
{ {
skipping to change at page 21, line 42 skipping to change at page 22, line 43
"property-map": { "property-map": {
"ipv4:192.0.2.0": {"pid": "pid2"}, "ipv4:192.0.2.0": {"pid": "pid2"},
"ipv4:192.0.2.16": {"pid": "pid2"}, "ipv4:192.0.2.16": {"pid": "pid2"},
"ipv4:192.0.2.64": {"pid": "pid1"}, "ipv4:192.0.2.64": {"pid": "pid1"},
"ipv4:192.0.2.128": {"pid": "defaultpid"}, "ipv4:192.0.2.128": {"pid": "defaultpid"},
"ipv4:192.0.2.0/26": {"pid": "pid1"}, "ipv4:192.0.2.0/26": {"pid": "pid1"},
"ipv4:192.0.2.0/30": {"pid": "pid2"} "ipv4:192.0.2.0/30": {"pid": "pid2"}
} }
} }
7.8. Filtered Property Map Example #4
The following example uses the Filtered Property Map resource to
request the "availbw" property for several abstract network elements.
POST /propmap/lookup/availbw HTTP/1.1
Host: alto.example.com
Accept: application/alto-propmap+json,application/alto-error+json
Content-Length: ###
Content-Type: application/alto-propmapparams+json
{
"entities" : [
"ane:L001",
"ane:Lae0",
"ane:L3eb ],
"properties" : [ "availbw" ]
}
HTTP/1.1 200 OK
Content-Length: ###
Content-Type: application/alto-propmap+json
{
"property-map": {
"ane:L001": {"availbw": "55"},
"ane:Lae0": {"availbw": "70"},
"ane:L3eb": {"availbw": "40"}
}
}
8. Security Considerations 8. Security Considerations
As discussed in Section 15 of [RFC7285], properties may have As discussed in Section 15 of [RFC7285], properties MAY have
sensitive customer-specific information. If this is the case, an sensitive customer-specific information. If this is the case, an
ALTO Server may limit access to those properties by providing several ALTO Server MAY limit access to those properties by providing several
different property maps. For non-sensitive properties, the ALTO different Property Maps. For non-sensitive properties, the ALTO
Server would provide a URI which accepts requests from any client. Server would provide a URI which accepts requests from any client.
Sensitive properties, on the other hand, would only be available via Sensitive properties, on the other hand, would only be available via
a secure URI which would require client authentication. a secure URI which would require client authentication.
Also, while technically this document does not introduce any security Also, while technically this document does not introduce any security
risks not inherent in the Endpoint Property Service defined by risks not inherent in the Endpoint Property Service defined by
[RFC7285], the GET-mode property map resource defined in this [RFC7285], the GET-mode property map resource defined in this
document does make it easier for a client to download large numbers document does make it easier for a client to download large numbers
of property values. Accordingly, an ALTO Server should limit GET- of property values. Accordingly, an ALTO Server SHOULD limit GET-
mode property maps for to properties which do not contain sensitive mode Property Maps to properties which do not contain sensitive data.
data.
9. IANA Considerations 9. IANA Considerations
This document defines additional application/alto-* media types, and This document defines additional application/alto-* media types, and
extends the ALTO endpoint property registry. extends the ALTO endpoint property registry.
9.1. application/alto-* Media Types 9.1. application/alto-* Media Types
This document registers two additional ALTO media types, listed in This document registers two additional ALTO media types, listed in
Table 1. Table 1.
+-------------+-------------------------+---------------+ +--------------+--------------------------+-----------------------+
| Type | Subtype | Specification | | Type | Subtype | Specification |
+-------------+-------------------------+---------------+ +--------------+--------------------------+-----------------------+
| application | alto-propmap+json | Section 4.1 | | application | alto-propmap+json | Section 4.1 |
| application | alto-propmapparams+json | Section 5.3 | | application | alto-propmapparams+json | Section 5.3 |
+-------------+-------------------------+---------------+ +--------------+--------------------------+-----------------------+
Table 1: Additional ALTO Media Types Table 1: Additional ALTO Media Types.
Type name: application Type name: application
Subtype name: This document registers multiple subtypes, as listed Subtype name: This document registers multiple subtypes, as listed
in Table 1. in Table 1.
Required parameters: n/a Required parameters: n/a
Optional parameters: n/a Optional parameters: n/a
Encoding considerations: Encoding considerations are identical to Encoding considerations: Encoding considerations are identical to
those specified for the "application/json" media type. See those specified for the "application/json" media type. See
[RFC7159]. [RFC7159].
Security considerations: Security considerations relating to the Security considerations: Security considerations related to the
generation and consumption of ALTO Protocol messages are discussed generation and consumption of ALTO Protocol messages are discussed
in Section 15 of [RFC7285]. in Section 15 of [RFC7285].
Interoperability considerations: This document specifies format of Interoperability considerations: This document specifies formats of
conforming messages and the interpretation thereof. conforming messages and the interpretation thereof.
Published specification: This document is the specification for Published specification: This document is the specification for
these media types; see Table 1 for the section documenting each these media types; see Table 1 for the section documenting each
media type. media type.
Applications that use this media type: ALTO servers and ALTO clients Applications that use this media type: ALTO servers and ALTO clients
either stand alone or are embedded within other applications. either stand alone or are embedded within other applications.
Additional information: Additional information: ~ Magic number(s): ~ n/a File extension(s): ~
This document uses the mime type to refer to protocol messages and
Magic number(s): n/a thus does not require a file extension. Macintosh file type code(s):
~ n/a
File extension(s): This document uses the mime type to refer to
protocol messages and thus does not require a file extension.
Macintosh file type code(s): n/a
Person & email address to contact for further information: See Person & email address to contact for further information: See
Authors' Addresses section. Authors' Addresses section.
Intended usage: COMMON Intended usage: COMMON
Restrictions on usage: n/a Restrictions on usage: n/a
Author: See Authors' Addresses section. Author: See Authors' Addresses section.
Change controller: Internet Engineering Task Force Change controller: Internet Engineering Task Force
(mailto:iesg@ietf.org). (mailto:iesg@ietf.org).
9.2. ALTO Entity Domain Registry 9.2. ALTO Entity Domain Registry
This document requests IANA to create and maintain the "ALTO Entity This document requests IANA to create and maintain the "ALTO Entity
Domain Registry", listed in Table 2. Domain Registry", listed in Table 2.
+------------+-------------------------+-------------------------+ +-------------+--------------------------+--------------------------+
| Identifier | Entity Address Encoding | Hierarchy & Inheritance | | Identifier | Entity Address Encoding | Hierarchy & Inheritance |
+------------+-------------------------+-------------------------+ +-------------+--------------------------+--------------------------+
| ipv4 | See Section 3.1.1 | See Section 3.1.3 | | ipv4 | See Section 3.1.1 | See Section 3.1.3 |
| ipv6 | See Section 3.1.2 | See Section 3.1.3 | | ipv6 | See Section 3.1.2 | See Section 3.1.3 |
| pid | See Section 3.2 | None | | pid | See Section 3.2 | None |
+------------+-------------------------+-------------------------+ | ane | See Section 3.4 | None |
+-------------+--------------------------+--------------------------+
Table 2: ALTO Entity Domain Names Table 2: ALTO Entity Domain Names.
This registry serves two purposes. First, it ensures uniqueness of This registry serves two purposes. First, it ensures uniqueness of
identifiers referring to ALTO entity domains. Second, it states the identifiers referring to ALTO entity domains. Second, it states the
requirements for allocated domain names. requirements for allocated domain names.
New ALTO entity domains are assigned after IETF Review [RFC5226] to New ALTO entity domains are assigned after IETF Review [RFC5226] to
ensure that proper documentation regarding the new ALTO entity ensure that proper documentation regarding the new ALTO entity
domains and their security considerations has been provided. RFCs domains and their security considerations has been provided. RFCs
defining new entity domains should indicate how an entity in a defining new entity domains SHOULD indicate how an entity in a
registered domain is encoded as an EntityName, and, if applicable, registered domain is encoded as an EntityName, and, if applicable,
the rules defining the entity hierarchy and property inheritance. the rules defining the entity hierarchy and property inheritance.
Updates and deletions of ALTO entity domains follow the same Updates and deletions of ALTO entity domains follow the same
procedure. procedure.
Registered ALTO entity domain identifiers MUST conform to the Registered ALTO entity domain identifiers MUST conform to the
syntactical requirements specified in Section 2.4. Identifiers are syntactical requirements specified in Section 2.3. Identifiers are
to be recorded and displayed as strings. to be recorded and displayed as strings.
It is RECOMMANDED that a new ALTO entity domain be registered when
the corresponding address type is registered based on ALTO Address
Type Registry [RFC7285].
Requests to add a new value to the registry MUST include the Requests to add a new value to the registry MUST include the
following information: following information:
o Identifier: The name of the desired ALTO entity domain. o Identifier: The name of the desired ALTO entity domain.
o Entity Address Encoding: The procedure for encoding the address of o Entity Address Encoding: The procedure for encoding the address of
an entity of the registered type as an EntityAddr (see an entity of the registered type as an EntityAddr (see
Section 2.3). Section 2.4).
o Hierarchy: If the entities form a hierarchy, the procedure for o Hierarchy: If the entities form a hierarchy, the procedure for
determining that hierarchy. determining that hierarchy.
o Inheritance: If entities can inherit property values from other o Inheritance: If entities can inherit property values from other
entities, the procedure for determining that inheritance. entities, the procedure for determining that inheritance.
o Security Considerations: In some usage scenarios, entity addresses o Security Considerations: In some usage scenarios, entity addresses
carried in ALTO Protocol messages may reveal information about an carried in ALTO Protocol messages MAY reveal information about an
ALTO client or an ALTO service provider. Applications and ALTO ALTO client or an ALTO service provider. Applications and ALTO
service providers using addresses of the registered type should be service providers using addresses of the registered type SHOULD be
made aware of how (or if) the addressing scheme relates to private made aware of how (or if) the addressing scheme relates to private
information and network proximity. information and network proximity.
This specification requests registration of the identifiers "ipv4", This specification requests registration of the identifiers "ipv4",
"ipv6" and "pid", as shown in Table 2. "ipv6" and "pid", as shown in Table 2.
9.3. ALTO Endpoint Property Type Registry 9.3. ALTO Endpoint Property Type Registry
The ALTO Endpoint Property Type Registry was created by [RFC7285]. The ALTO Endpoint Property Type Registry was created by [RFC7285].
If possible, the name of that registry should be changed to "ALTO If possible, the name of that registry SHOULD be changed to "ALTO
Entity Property Type Registry", to indicate that it is not restricted Entity Property Type Registry", to indicate that it is not restricted
to Endpoint Properties. If it is not feasible to change the name, to Endpoint Properties. If it is not feasible to change the name,
the description must be amended to indicate that it registers the description MUST be amended to indicate that it registers
properties in all domains, rather than just the Internet address properties in all domains, rather than just the Internet address
domain. domain.
10. References 10. References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", RFC 2119, BCP 14, March 1997. Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, <https://www.rfc-
editor.org/info/rfc2119>.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", RFC 3986, Resource Identifier (URI): Generic Syntax", STD 66,
January 2005. RFC 3986, DOI 10.17487/RFC3986, January 2005,
<https://www.rfc-editor.org/info/rfc3986>.
[RFC4632] Fuller, V. and T. Li, "Classless Inter-domain Routing [RFC4632] Fuller, V. and T. Li, "Classless Inter-domain Routing
(CIDR): The Internet Address Assignment and Aggregation (CIDR): The Internet Address Assignment and Aggregation
Plan", RFC 4632, BCP 122, August 2006. Plan", BCP 122, RFC 4632, DOI 10.17487/RFC4632, August
2006, <https://www.rfc-editor.org/info/rfc4632>.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", RFC 5226, BCP 26, IANA Considerations Section in RFCs", RFC 5226,
May 2008. DOI 10.17487/RFC5226, May 2008, <https://www.rfc-
editor.org/info/rfc5226>.
[RFC5952] Kawamura, S. and M. Kawashima, "A Recommendation for IPv6 [RFC5952] Kawamura, S. and M. Kawashima, "A Recommendation for IPv6
Address Text Representation", RFC 5952, August 2010. Address Text Representation", RFC 5952,
DOI 10.17487/RFC5952, August 2010, <https://www.rfc-
[RFC7159] Bray, T., "The JavaScript Object Notation (JSON) Data editor.org/info/rfc5952>.
Interchange Format", RFC 7159, March 2014.
[RFC7285] Almi, R., Penno, R., Yang, Y., Kiesel, S., Previdi, S., [RFC7159] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Roome, W., Shalunov, S., and R. Woundy, "Application-Layer Interchange Format", RFC 7159, DOI 10.17487/RFC7159, March
Traffic Optimization (ALTO) Protocol", RFC 7285, September 2014, <https://www.rfc-editor.org/info/rfc7159>.
2014.
[ID-draft-yang-alto-path-vector-04] [RFC7285] Alimi, R., Ed., Penno, R., Ed., Yang, Y., Ed., Kiesel, S.,
Bernstein, G., Gao, K., Lee, Y., Roome, W., Scharf, M., Previdi, S., Roome, W., Shalunov, S., and R. Woundy,
and Y. Yang, "ALTO Topology Extension: Path Vector as a "Application-Layer Traffic Optimization (ALTO) Protocol",
Cost Mode", March 2017. RFC 7285, DOI 10.17487/RFC7285, September 2014,
<https://www.rfc-editor.org/info/rfc7285>.
[ID-draft-yang-alto-topology-06] [I-D.ietf-alto-path-vector]
Bernstein, G., Lee, Y., Roome, W., Scharf, M., and Y. Bernstein, G., Chen, S., Gao, K., Lee, Y., Roome, W.,
Yang, "ALTO Topology Extensions: Node-Link Graphs", March Scharf, M., Yang, Y., and J. Zhang, "ALTO Extension: Path
2015. Vector Cost Mode", draft-ietf-alto-path-vector-00 (work in
progress), May 2017.
Authors' Addresses Authors' Addresses
Wendy Roome Wendy Roome
Nokia Bell Labs Nokia Bell Labs
600 Mountain Ave, Rm 3B-324 600 Mountain Ave, Rm 3B-324
Murray Hill, NJ 07974 Murray Hill, NJ 07974
USA USA
Phone: +1-908-582-7974 Phone: +1-908-582-7974
Email: wendy@roome.com Email: wendy@roome.com
Y. Yang Shiwei Dawn Chen
Tongji University
4800 Caoan Road
Shanghai 201804
China
Email: dawn_chen_f@hotmail.com
Xin (Tony) Wang
Tongji University
4800 CaoAn Road
Shanghai 210000
China
Email: xinwang2014@hotmail.com
Y. Richard Yang
Yale University Yale University
51 Prospect Street 51 Prospect Street
New Haven, CT 06511 New Haven, CT 06511
USA USA
Phone: +1-203-432-6400 Phone: +1-203-432-6400
Email: yry@cs.yale.edu Email: yry@cs.yale.edu
Jingxuan Jensen Zhang
Tongji University
4800 Caoan Road
Shanghai 201804
China
Email: jingxuan.n.zhang@gmail.com
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