draft-ietf-dmm-ondemand-mobility-08.txt   draft-ietf-dmm-ondemand-mobility-09.txt 
DMM Working Group A. Yegin DMM Working Group A. Yegin
Internet-Draft Actility Internet-Draft Actility
Intended status: Informational D. Moses Intended status: Informational D. Moses
Expires: June 1, 2017 Intel Expires: June 15, 2017 Intel
K. Kweon K. Kweon
J. Lee J. Lee
J. Park J. Park
Samsung Samsung
S. Jeon S. Jeon
Sungkyunkwan University Sungkyunkwan University
November 28, 2016 December 12, 2016
On Demand Mobility Management On Demand Mobility Management
draft-ietf-dmm-ondemand-mobility-08 draft-ietf-dmm-ondemand-mobility-09
Abstract Abstract
Applications differ with respect to whether they need IP session Applications differ with respect to whether they need IP session
continuity and/or IP address reachability. The network providing the continuity and/or IP address reachability. The network providing the
same type of service to any mobile host and any application running same type of service to any mobile host and any application running
on the host yields inefficiencies. This document describes a on the host yields inefficiencies. This document describes a
solution for taking the application needs into account in selectively solution for taking the application needs into account in selectively
providing IP session continuity and IP address reachability on a per- providing IP session continuity and IP address reachability on a per-
socket basis. socket basis.
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Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on June 1, 2017. This Internet-Draft will expire on June 15, 2017.
Copyright Notice Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the Copyright (c) 2016 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
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3.2. Granularity of Selection . . . . . . . . . . . . . . . . 5 3.2. Granularity of Selection . . . . . . . . . . . . . . . . 5
3.3. On Demand Nature . . . . . . . . . . . . . . . . . . . . 5 3.3. On Demand Nature . . . . . . . . . . . . . . . . . . . . 5
3.4. Conveying the Selection . . . . . . . . . . . . . . . . . 6 3.4. Conveying the Selection . . . . . . . . . . . . . . . . . 6
4. Backwards Compatibility Considerations . . . . . . . . . . . 9 4. Backwards Compatibility Considerations . . . . . . . . . . . 9
4.1. Applications . . . . . . . . . . . . . . . . . . . . . . 9 4.1. Applications . . . . . . . . . . . . . . . . . . . . . . 9
4.2. IP Stack in the Mobile Host . . . . . . . . . . . . . . . 9 4.2. IP Stack in the Mobile Host . . . . . . . . . . . . . . . 9
4.3. Network Infrastructure . . . . . . . . . . . . . . . . . 10 4.3. Network Infrastructure . . . . . . . . . . . . . . . . . 10
5. Summary of New Definitions . . . . . . . . . . . . . . . . . 10 5. Summary of New Definitions . . . . . . . . . . . . . . . . . 10
6. Security Considerations . . . . . . . . . . . . . . . . . . . 10 6. Security Considerations . . . . . . . . . . . . . . . . . . . 10
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 10 8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 11
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 11
10.1. Normative References . . . . . . . . . . . . . . . . . . 11 10.1. Normative References . . . . . . . . . . . . . . . . . . 11
10.2. Informative References . . . . . . . . . . . . . . . . . 11 10.2. Informative References . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12
1. Introduction 1. Introduction
In the context of Mobile IP [RFC5563][RFC6275][RFC5213][RFC5944], In the context of Mobile IP [RFC5563][RFC6275][RFC5213][RFC5944],
following two attributes are defined for the IP service provided to following two attributes are defined for the IP service provided to
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and IP address reachability should be be provided only when needed. and IP address reachability should be be provided only when needed.
Furthermore, when an application needs session continuity, it may be Furthermore, when an application needs session continuity, it may be
able to satisfy that need by using a solution above the IP layer, able to satisfy that need by using a solution above the IP layer,
such as MPTCP [RFC6824], SIP mobility [RFC3261], or an application- such as MPTCP [RFC6824], SIP mobility [RFC3261], or an application-
layer mobility solution. Those higher-layer solutions are not layer mobility solution. Those higher-layer solutions are not
subject to the same issues that arise with the use of Mobile IP since subject to the same issues that arise with the use of Mobile IP since
they can utilize the most direct data path between the end-points. they can utilize the most direct data path between the end-points.
But, if Mobile IP is being applied to the mobile host, those higher- But, if Mobile IP is being applied to the mobile host, those higher-
layer protocols are rendered useless because their operation is layer protocols are rendered useless because their operation is
inhibited by the Mobile IP. Since Mobile IP ensures the IP address inhibited by the Mobile IP. Since Mobile IP ensures that the IP
of the mobile host remains fixed (despite the location and movement address of the mobile host remains fixed (despite the location and
of the mobile host), the higher-layer protocols never detect the IP- movement of the mobile host), the higher-layer protocols never detect
layer change and never engage in mobility management. the IP-layer change and never engage in mobility management.
This document proposes a solution for the applications running on the This document proposes a solution for the applications running on the
mobile host to indicate whether they need IP session continuity or IP mobile host to indicate whether they need IP session continuity or IP
address reachability. The network protocol stack on the mobile host, address reachability. The network protocol stack on the mobile host,
in conjunction with the network infrastructure, would provide the in conjunction with the network infrastructure, would provide the
required type of IP service. It is for the benefit of both the users required type of IP service. It is for the benefit of both the users
and the network operators not to engage an extra level of service and the network operators not to engage an extra level of service
unless it is absolutely necessary. So it is expected that unless it is absolutely necessary. So it is expected that
applications and networks compliant with this specification would applications and networks compliant with this specification would
utilize this solution to use network resources more efficiently. utilize this solution to use network resources more efficiently.
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- Fixed IP Address - Fixed IP Address
A Fixed IP address is an address with a guarantee to be valid for a A Fixed IP address is an address with a guarantee to be valid for a
very long time, regardless of whether it is being used in any packet very long time, regardless of whether it is being used in any packet
to/from the mobile host, or whether or not the mobile host is to/from the mobile host, or whether or not the mobile host is
connected to the network, or whether it moves from one point-of- connected to the network, or whether it moves from one point-of-
attachment to another (with a different subnet or IP prefix) while it attachment to another (with a different subnet or IP prefix) while it
is connected. is connected.
Fixed IP address are required by applications that need both IP Fixed IP addresses are required by applications that need both IP
session continuity and IP address reachability. session continuity and IP address reachability.
- Session-lasting IP Address - Session-lasting IP Address
A session-lasting IP address is an address with a guarantee to be A session-lasting IP address is an address with a guarantee to be
valid through-out the IP session(s) for which it was requested. It valid throughout the IP session(s) for which it was requested. It is
is guaranteed to be valid even after the mobile host had moved from guaranteed to be valid even after the mobile host had moved from one
one point-of-attachment to another (with a different subnet or IP point-of-attachment to another (with a different subnet or IP
prefix). prefix).
Session-lasting IP addresses are required by applications that need Session-lasting IP addresses are required by applications that need
IP session continuity but do not need IP address reachability. IP session continuity but do not need IP address reachability.
- Non-persistent IP Address - Non-persistent IP Address
This type of IP address provides neither IP session continuity nor IP This type of IP address provides neither IP session continuity nor IP
address reachability. The IP address is obtained from the serving IP address reachability. The IP address is obtained from the serving IP
gateway and it is not maintained across gateway changes. In other gateway and it is not maintained across gateway changes. In other
words, the IP address may be released and replaced by a new IP words, the IP address may be released and replaced by a new IP
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Applications running as servers at a published IP address require a Applications running as servers at a published IP address require a
Fixed IP Address. Long-standing applications (e.g., an SSH session) Fixed IP Address. Long-standing applications (e.g., an SSH session)
may also require this type of address. Enterprise applications that may also require this type of address. Enterprise applications that
connect to an enterprise network via virtual LAN require a Fixed IP connect to an enterprise network via virtual LAN require a Fixed IP
Address. Address.
Applications with short-lived transient IP sessions can use Session- Applications with short-lived transient IP sessions can use Session-
lasting IP Addresses. For example: Web browsers. lasting IP Addresses. For example: Web browsers.
Applications with very short IP sessions, such as DNS client and Applications with very short IP sessions, such as DNS clients and
instant messengers, can utilize Non-persistent IP Addresses. Even instant messengers, can utilize Non-persistent IP Addresses. Even
though they could very well use a Fixed of Session-lasting IP though they could very well use Fixed or Session-lasting IP
Addresses, the transmission latency would be minimized when a Non- Addresses, the transmission latency would be minimized when a Non-
persistent IP Address is used. persistent IP Addresses are used.
The network creates the desired guarantee (Fixed, Session-lasting or The network creates the desired guarantee (Fixed, Session-lasting or
Non-persistent) by either assigning an IP address (as part of a Non-persistent) by either assigning the address prefix (as part of a
stateful IP address generation), or by assigning the address prefix stateless address generation process), or by assigning an IP address
(as part of a stateless address generation process). (as part of a stateful IP address generation).
The exact mechanism of prefix or address assignment is outside the
scope of this specification.
3.2. Granularity of Selection 3.2. Granularity of Selection
The IP address type selection is made on a per-socket granularity. The IP address type selection is made on a per-socket granularity.
Different parts of the same application may have different needs. Different parts of the same application may have different needs.
For example, control-plane of an application may require a Fixed IP For example, control-plane of an application may require a Fixed IP
Address in order to stay reachable, whereas data-plane of the same Address in order to stay reachable, whereas data-plane of the same
application may be satisfied with a Session-lasting IP Address. application may be satisfied with a Session-lasting IP Address.
3.3. On Demand Nature 3.3. On Demand Nature
At any point in time, a mobile host may have a combination of IP At any point in time, a mobile host may have a combination of IP
addresses configured. Zero or more Non-persistent, zero or more addresses configured. Zero or more Non-persistent, zero or more
Session-lasting, and zero or more Fixed IP addresses may be Session-lasting, and zero or more Fixed IP addresses may be
configured on the IP stack of the host. The combination may be as a configured on the IP stack of the host. The combination may be as a
result of the host policy, application demand, or a mix of the two. result of the host policy, application demand, or a mix of the two.
When an application requires a specific type of IP address and such When an application requires a specific type of IP address and such
address is not already configured on the host, the IP stack shall address is not already configured on the host, the IP stack shall
attempt to configure one. For example, a host may not always have a attempt to configure one. For example, a host may not always have a
Session-lasting IP address available. In case an application Session-lasting IP address available. When an application requests
requests one, the IP stack shall make an attempt to configure one by one, the IP stack shall make an attempt to configure one by issuing a
issuing a request to the network. If the operation fails, the IP request to the network. If the operation fails, the IP stack shall
stack shall fail the associated socket request. If successful, a fail the associated socket request. If successful, a Session-lasting
Session-lasting IP Address gets configured on the mobile host. If IP Address gets configured on the mobile host. If another socket
another socket requests a Session-lasting IP address at a later time, requests a Session-lasting IP address at a later time, the same IP
the same IP address may be served to that socket as well. When the address may be served to that socket as well. When the last socket
last socket using the requested IP address is closed, the IP address using the same configured IP address is closed, the IP address may be
may be released or kept for future applications that may be launched released or kept for future applications that may be launched and
and require a Session-lasting IP address. require a Session-lasting IP address.
In some cases it might be preferable for the mobile host to request a In some cases it might be preferable for the mobile host to request a
new Session-lasting IP address for a new opening of an IP session new Session-lasting IP address for a new opening of an IP session
(even though one was already assigned to the mobile host by the (even though one was already assigned to the mobile host by the
network and might be in use in a different, already active IP network and might be in use in a different, already active IP
session). It is out of the scope of this specification to define session). It is outside the scope of this specification to define
criteria for selecting to use available addresses or choose to criteria for selecting to use available addresses or choose to
request new ones. It supports both alternatives (and any request new ones. It supports both alternatives (and any
combination). combination).
It is outside of the scope of this specification to define how the It is outside the scope of this specification to define how the host
host requests a specific type of address (Fixed, Session-lasting or requests a specific type of address (Fixed, Session-lasting or Non-
Non-persistent) and how the network indicates the type of address in persistent) and how the network indicates the type of address in its
its advertisement of addresses (or in its reply to an address advertisement of IP prefixes or addresses (or in its reply to a
request). request).
The following are matters of policy, which may be dictated by the The following are matters of policy, which may be dictated by the
host itself, the network operator, or the system architecture host itself, the network operator, or the system architecture
standard: standard:
- The initial set of IP addresses configured on the host at the boot - The initial set of IP addresses configured on the host at boot
time. time.
- Permission to grant various types of IP addresses to a requesting - Permission to grant various types of IP addresses to a requesting
application. application.
- Determination of a default address type when an application does - Determination of a default address type when an application does
not make any explicit indication, whether it already supports the not make any explicit indication, whether it already supports the
required API or it is just a legacy application. required API or it is just a legacy application.
3.4. Conveying the Selection 3.4. Conveying the Selection
The selection of the address type is conveyed from the applications The selection of the address type is conveyed from the applications
to the IP stack in a way to influence the source address selection to the IP stack in oredr to influence the source address selection
algorithm [RFC6724]. algorithm [RFC6724].
The current source address selection algorithm operates on the The current source address selection algorithm operates on the
available set of IP addresses when selecting an address. According available set of IP addresses, when selecting an address. According
to the proposed solution, if the requested type IP address is not to the proposed solution, if the requested IP address type is not
available at the time of the request, the IP stack shall make an available at the time of the request, the IP stack shall make an
attempt to configure one such IP address. The selected IP address attempt to configure one such IP address. The selected IP address
shall be compliant with the requested IP address type, whether it is shall be compliant with the requested IP address type, whether it is
selected among available addresses or dynamically configured. In the selected among available addresses or dynamically configured. In the
absence of a matching type (because it is not available and not absence of a matching type (because it is not available and not
configurable on demand), the source address selection algorithm shall configurable on demand), the source address selection algorithm shall
return an empty set. return an empty set.
A Socket API-based interface for enabling applications to influence A Socket API-based interface for enabling applications to influence
the source address selection algorithm is described in [RFC5014]. the source address selection algorithm is described in [RFC5014].
That specification defines IPV6_ADDR_PREFERENCES option at the That specification defines IPV6_ADDR_PREFERENCES option at the
IPPROTO_IPV6 level. That option can be used with setsockopt() and IPPROTO_IPV6 level. That option can be used with setsockopt() and
getsockopt() calls to set and get address selection preferences. getsockopt() calls to set and get address selection preferences.
Furthermore, that RFC also specifies two flags that relate to IP Furthermore, that RFC also specifies two flags that relate to IP
mobility management: IPV6_PREFER_SRC_HOME and IPV6_PREFER_SRC_COA. mobility management: IPV6_PREFER_SRC_HOME and IPV6_PREFER_SRC_COA.
These flags are used for influencing the source address selection to These flags are used for influencing the source address selection to
prefer either a Home Address or a Care-of Address. prefer either a Home Address or a Care-of Address.
Unfortunately, these flags do not satisfy the aforementioned needs Unfortunately, these flags do not satisfy the aforementioned needs
due to the following reasons, therefore new flags are proposed in due to the following reasons:
this document:
- Current flags indicate a "preference" whereas there is a need for - Current flags indicate a "preference" whereas there is a need for
indicating "requirement". Source address selection algorithm does indicating "requirement". Source address selection algorithm does
not have to produce an IP address compliant with the "preference" , not have to produce an IP address compliant with the "preference" ,
but it has to produce an IP address compliant with the "requirement". but it has to produce an IP address compliant with the "requirement".
- Current flags influence the selection made among available IP - Current flags influence the selection made among available IP
addresses. The new flags force the IP stack to configure a compliant addresses. The new flags force the IP stack to configure a compliant
IP address if none is available at the time of the request. IP address if none is available at the time of the request.
- The Home vs. Care-of Address distinction is not sufficient to - The Home vs. Care-of Address distinction is not sufficient to
capture the three different types of IP addresses described in capture the three different types of IP addresses described in
Section 2.1. Section 2.1.
The following new flags are defined in this document and they shall The following new flags are defined in this document and they shall
be used with Socket API in compliance with the [RFC5014]: be used with Socket API in compliance with [RFC5014]:
IPV6_REQUIRE_FIXED_IP /* Require a Fixed IP address as source */ IPV6_REQUIRE_FIXED_IP /* Require a Fixed IP address as source */
IPV6_REQUIRE_SESSION_LASTING_IP /* Require a Session-lasting IP IPV6_REQUIRE_SESSION_LASTING_IP /* Require a Session-lasting IP
address as source */ address as source */
IPV6_REQUIRE_NON-PERSISTENT_IP /* Require a Non-persistent IP address IPV6_REQUIRE_NON-PERSISTENT_IP /* Require a Non-persistent IP address
as source */ as source */
Only one of these flags may be set on the same socket. If an Only one of these flags may be set on the same socket. If an
application attempts to set more than one flag, the most recent application attempts to set more than one flag, the most recent
setting will be the one in effect. setting will be the one in effect.
When any of these new flags is used, then the IPV6_PREFER_SRC_HOME When any of these new flags is used, the IPV6_PREFER_SRC_HOME and
and IPV6_PREFER_SRC_COA flags, if used, shall be ignored. IPV6_PREFER_SRC_COA flags, if used, shall be ignored.
These new flags are used with setsockopt()/getsockopt(), These new flags are used with setsockopt()/getsockopt(),
getaddrinfo(), and inet6_is_srcaddr() functions [RFC5014]. Similar getaddrinfo(), and inet6_is_srcaddr() functions [RFC5014]. Similar
with the setsockopt()/getsockopt() calls, getaddrinfo() call shall to the setsockopt()/getsockopt() calls, the getaddrinfo() call shall
also trigger configuration of the required type IP address, if one is also trigger configuration of the required IP address type, if one is
not already available. When the new flags are used with not already available. When the new flags are used with
getaddrinfo() and the triggered configuration fails, the getaddrinfo() and the triggered configuration fails, the
getaddrinfo() call shall ignore that failure (i.e., not return an getaddrinfo() call shall ignore that failure (i.e., not return an
error code to indicate that failure). Only the setsockopt() shall error code to indicate that failure). Only the setsockopt() shall
return an error when configuration of the requested type IP address return an error when configuration of the requested IP address type
fails. fails.
When the IP stack is required to assign a source IP address of a When the IP stack is required to use a source IP address of a
specified type, it can perform one of the following: It can assigned specified type, it can perform one of the following: It can use an
a preconfigured address (if one exists) or request a new one from the existing address (if it has one), or it can create a new one from an
network. Using an existing address is instantaneous but might yield existing prefix of the desired type. If the host does not already
a less optimal route (if a hand-off event occurred since its have an IPv6 prefix of the specific type, it can request one from the
configuration), on the other hand, acquiring a new IP address from network.
the network may take some time (due to signaling exchange with the
network). Using an existing address from an existing prefix is faster but might
yield a less optimal route (if a hand-off event occurred since its
configuration), on the other hand, acquiring a new IP prefix from the
network may take some time (due to signaling exchange with the
network) and may fail due to network policies.
An additional new flag - ON_NET flag - enables the application to An additional new flag - ON_NET flag - enables the application to
direct the IP stack whether to use a preconfigured source IP address direct the IP stack whether to use a preconfigured source IP address
(if exists) or to request a new one from the current serving network: (if exists) or to request a new IPv6 prefix from the current serving
network and configure a new IP address:
IPV6_REQUIRE_SRC_ON_NET /* Set IP stack address allocation behavior IPV6_REQUIRE_SRC_ON_NET /* Set IP stack address allocation behavior
*/ */
If set, the IP stack will request a new IP address of the desired If set, the IP stack will request a new IPv6 prefix of the desired
type from the current serving network. If reset, the IP stack will type from the current serving network and configure a new source IP
use a preconfigured one if exists. If there is no preconfigured IP address. If reset, the IP stack will use a preconfigured one if
address of the desired type, the IP stack will request a new one from exists. If there is no preconfigured IP address of the desired type,
the current serving network (regardless of whether this flag is set the IP stack will request a IPv6 prefix from the current serving
or reset). network (regardless of whether this flag is set or not).
The ON_NET flag must be used together with one of the 3 flags defined The ON_NET flag must be used together with one of the 3 flags defined
above. If ON_NET flag is used without any of these flags, it must be above. If ON_NET flag is used without any of these flags, it must be
ignored. If the ON_NET flag is not used, the IP stack is free to ignored. If the ON_NET flag is not used, the IP stack is free to
either use an existing IP address (if preconfigured) or access the either use an existing IP address (if preconfigured) or access the
network to configure a new one (the decision is left to network to configure a new one (the decision is left to
implementation). implementation).
The following new error codes are also defined in the document and The following new error codes are also defined in the document and
will be used in the Socket API in compliance with [RFC5014]. will be used in the Socket API in compliance with [RFC5014].
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- The network infrastructure - The network infrastructure
4.1. Applications 4.1. Applications
Legacy applications that do not support the new flags will use the Legacy applications that do not support the new flags will use the
legacy API to the IP stack and will not enjoy On-Demand Mobility legacy API to the IP stack and will not enjoy On-Demand Mobility
feature. feature.
Applications using the new flags must be aware that they may be Applications using the new flags must be aware that they may be
executed in environments that do not support On-Demand Mobility executed in environments that do not support the On-Demand Mobility
feature. Such environments may include legacy IP stack in the mobile feature. Such environments may include legacy IP stack in the mobile
host, legacy network infrastructure, or both. In either case, the host, legacy network infrastructure, or both. In either case, the
API will return an error code and the invoking applications must API will return an error code and the invoking applications must
respond with using legacy calls without On-Demand Mobility feature. respond with using legacy calls without the On-Demand Mobility
feature.
4.2. IP Stack in the Mobile Host 4.2. IP Stack in the Mobile Host
New IP stacks must continue to support all legacy operations. If an New IP stacks must continue to support all legacy operations. If an
application does not use On-Demand Mobility feature, the IP stack application does not use On-Demand Mobility feature, the IP stack
must respond in a legacy manner. must respond in a legacy manner.
If the network infrastructure supports On-Demand Mobility feature, If the network infrastructure supports On-Demand Mobility feature,
the IP stack should follow the application request: If the the IP stack should follow the application request: If the
application requests a specific address type, the stack should application requests a specific address type, the stack should
forward this request to the network. If the application does not forward this request to the network. If the application does not
request an address type, the IP stack must not request an address request an address type, the IP stack must not request an address
type and leave it to the network's default behavior to choose the type and leave it to the network's default behavior to choose the
type of the allocated IP address. If an IP address was already type of the allocated IP prefix. If an IP prefix was already
allocated to the host, the IP stack uses it and may not request a new allocated to the host, the IP stack uses it and may not request a new
one from the network. one from the network.
4.3. Network Infrastructure 4.3. Network Infrastructure
The network infrastructure may or may not support the On-Demand The network infrastructure may or may not support the On-Demand
Mobility feature. How the IP stack on the host and the network Mobility feature. How the IP stack on the host and the network
infrastructure behave in case of a compatibility issue is outside the infrastructure behave in case of a compatibility issue is outside the
scope of this API specification. scope of this API specification.
skipping to change at page 11, line 19 skipping to change at page 11, line 25
Younghan Kim Younghan Kim
Soongsil University, Korea Soongsil University, Korea
Email: younghak@ssu.ac.kr Email: younghak@ssu.ac.kr
John Kaippallimalil John Kaippallimalil
Huawei, USA Huawei, USA
Email: john.kaippallimalil@huawei.com Email: john.kaippallimalil@huawei.com
9. Acknowledgements 9. Acknowledgements
We would like to thank Alexandru Petrescu, Jouni Korhonen, and Sri We would like to thank Alexandru Petrescu, Jouni Korhonen, Sri
Gundavelli for their valuable comments and suggestions on this work. Gundavelli, and Lorenzo Colitti for their valuable comments and
suggestions on this work.
10. References 10. References
10.1. Normative References 10.1. Normative 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", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>. <http://www.rfc-editor.org/info/rfc2119>.
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