Internet Engineering Task Force S. Bhandari
Internet-Draft G. Halwasia
Intended status: Standards Track S. Bandi
Expires: January 17, 2013 S. Gundavelli
Cisco Systems
H. Deng
China Mobile
L. Thiebaut
Alcatel-Lucent
July 16, 2012
DHCPv6 class based prefix
draft-bhandari-dhc-class-based-prefix-03
Abstract
DHCPv6 defines class based allocation of IA_NA and IA_TA IPv6
addresses. This document extends DHCPv6 prefix delegation with class
based prefix allocation. It defines a new usage class option to
classify a prefix. It defines the behavior of a DHCPv6 client
requesting a prefix to include the class of the prefix to be
allocated and the DHCPv6 server behavior to select and offer a prefix
from a given class. It discusses how IA_NA can be requested and
assigned from a specific usage class.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
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and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on January 17, 2013.
Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Motivation . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
1.3. Requirements Language . . . . . . . . . . . . . . . . . . 4
2. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Usage Class Option . . . . . . . . . . . . . . . . . . . . 5
2.2. Consideration for different DHCPv6 entities . . . . . . . 6
2.2.1. Requesting Router Behavior for IA_PD allocation . . . 6
2.2.2. Delegating Router Behavior for IA_PD allocation . . . 7
2.2.3. DHCPv6 Client Behavior for IA_NA allocation . . . . . 7
2.2.4. DHCPv6 Server Behavior for IA_NA allocation . . . . . 8
2.3. Usage . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.3.1. OPTION_USAGE_CLASS Values . . . . . . . . . . . . . . 8
2.3.2. Class based prefix and IA_NA allocation . . . . . . . 9
2.3.3. Class based prefix and IA_PD allocation . . . . . . . 9
2.3.4. Class based prefix and SLAAC . . . . . . . . . . . . . 9
2.3.5. Class based Information-Request . . . . . . . . . . . 10
2.3.6. Class based prefix and applications . . . . . . . . . 10
3. Example Application . . . . . . . . . . . . . . . . . . . . . 10
3.1. Class based prefix delegation . . . . . . . . . . . . . . 12
3.2. IPv6 address assignment from class based prefix . . . . . 12
4. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 13
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
5.1. OPTION_USAGE_CLASS values . . . . . . . . . . . . . . . . 13
6. Security Considerations . . . . . . . . . . . . . . . . . . . 14
7. Change History (to be removed prior to publication as an
RFC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
8.1. Normative References . . . . . . . . . . . . . . . . . . . 14
8.2. Informative References . . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15
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1. Introduction
DHCPv6 based prefix delegation as defined in [RFC3633] is a mechanism
for the delegation of IPv6 prefixes using DHCPv6 options. Through
these options, a delegating router can delegate prefixes to
authorized requesting routers. If the requesting router has to
function as a DHCPv6 server there needs to be additional information
in the delegated prefix that helps the requesting router to select
the address allocation for the DHCPv6 client it serves, from one of
the available delegated prefixes.
One way to select an address or longer prefix (from a delegated
prefix) to be allocated by a requesting router playing the role of a
DHCPv6 server is by introducing additional options in IA_PD to be
matched with options for address selection in the DHCPv6 SOLICIT
message. [RFC3315] defines the OPTION_USER_CLASS option which is
used for selecting address for assignment. But the OPTION_USER_CLASS
option is only loosely defined and it can hardly be used in mobile
environment where a DHCPv6 client, the DHCPv6 server or requesting
router and the delegating Router may belong to different
organizations.
This document introduces OPTION_USAGE_CLASS option in IA_PD option
for the purpose of selecting a prefix for further delegation either
via IA_NA or IA_PD DHCPv6 request. It defines the behavior of the
DHCPv6 server, the DHCPv6 prefix requesting router and the DHCPv6
client to use this option.
In IPv6 a network interface can acquire multiple addresses from the
same scope. In this case application need to have additional
information about the prefix configured on the interface for source
address selection. Since the network address can be configured via
DHCPv6 as defined in [RFC3315] or via Stateless Address
Autoconfiguration (SLAAC) as defined in [RFC4862], additional
information of a prefix can be provided via DHCPv6 or via IPv6 Router
Advertisement (RA).
1.1. Motivation
In this section motivation for class based prefix delegation that
qualifies the delegated prefix with additional class information is
described in the context of mobile networks. The class information
attached to a delegated prefix helps to distinguish property of a
delegated IPv6 prefix and selection of the prefix by different
applications using it.
In the mobile network architecture, there is a mobile router which
functions as a IP network gateway and provides IP connectivity to
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mobile nodes. Mobile router can be the requesting router requesting
delegated IPv6 prefix using DHCPv6. Mobile router can assume the
role of DHCPv6 server for mobile nodes(DHCPv6 clients) attached to
it. A mobile node in mobile network architecture can be associated
with multiple IPv6 prefixes belonging to different domains for e.g.
home address prefix, care of address prefix as specified in
[RFC3775].
The delegated prefixes when seen from the mobile router perspective
appear to be like any other prefix, but each prefixes have different
properties referred to as "Prefix Color" in the mobile networks.
Some delegated prefixes may be topologically local and some may be
remote prefixes anchored on a global anchor, but available to the
local anchor by means of tunnel setup in the network between the
local and global anchor. Some may be local with low latency
characteristics suitable for voice call break-out, some may have
global mobility support. So, the prefixes have different properties
and it is required for the application using the prefix to learn
about this property in order to use it intelligently. There is
currently no semantics in DHCPv6 prefix delegation that can carry
this information to specify properties of a delegated prefix. In
this scenario, the mobile router is unable to further delegate a
longer prefix intelligently based on properties of the prefix learnt.
1.2. Terminology
This document uses the terminology defined in [RFC2460], [RFC3315]
and [RFC3633].
1.3. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
2. Overview
This section defines usage class option in IA_PD and IA_NA to aid
class based prefix delegation and address assignment. This section
defines the behavior of the delegating router, the requesting router
and the DHCPv6 client. It defines also usage class option in the
context of a DHCP information request from a DHCP client to a DHCP
server.
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2.1. Usage Class Option
The format of the DHCPv6 usage class option is shown below.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OPTION_USAGE_CLASS | option-length(2) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Class | ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- ~
~ Vendor Class Data (Optional,variable length) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
option-code: OPTION_USAGE_CLASS (TBD)
option-length: 2 + Length of Vendor class information
if present
Class: 16 bit numeric value maintained as
OPTION_USAGE_CLASS enumeration in
IANA registered namespace
Vendor Class Data: If the value of Class (3) indicates it is
vendor specified additional vendor
specified data of variable length will be
attached in the form specified below:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OPTION_USAGE_CLASS | option-length(2) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Class | Enterprise ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Enterprise ID(4) | Vendor Class length(2) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Vendor Class Data (Variable length) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Enterprise ID: The vendor's 32-bit Enterprise Number as
registered with IANA [IANAEnterprise]
Vendor Class Length: 2, length of vendor class data that follows
Vendor Class Data: Binary data as defined by the vendor.
For e.g. 3gpp can specify this data to be
Application providers network domain string
The class values are maintained in OPTION_USAGE_CLASS values
enumeration explained in Section Section 2.3.1.
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2.2. Consideration for different DHCPv6 entities
The model of operation of communicating prefixes to be used by a
DHCPv6 server is as follows. A requesting router requests prefix(es)
from the delegating router, as described in Section 2.2.1. A
delegating router is provided IPv6 prefixes to be delegated to the
requesting router. Examples of ways in which the delegating router
is provided these prefixes are:
o Configuration
o Prefix delegated via a DHCPv6 request to another DHCPv6 server
o Using a Authentication Authorization Accounting (AAA) protocol
like RADIUS [RFC2865]
The delegating router chooses prefix(es) for delegation, and responds
with prefix(es) to the requesting router along with additional
options in the allocated prefix as described in Section 2.2.2. The
requesting router is then responsible for the delegated prefix(es)
after the DHCPv6 REQUEST message exchange. For example, the
requesting router may create DHCPv6 server configuration pools from
the delegated prefix, and function as a DHCPv6 Server. When the
requesting router then receives a DHCPv6 IA_NA requests it can select
the address to be allocated based on the OPTION_USER_CLASS or
OPTION_USAGE_CLASS options received in IA_NA request or any of the
other methods as described in Section 2.3.1.
2.2.1. Requesting Router Behavior for IA_PD allocation
DHCPv6 requesting router can request for prefixes in the following
ways:
o In the SOLICIT message within the IA_PD Prefix option, it MAY
include OPTION_USAGE_CLASS requesting prefix delegation for the
specific class indicated in the OPTION_USAGE_CLASS option. It can
include multiple IA_PD Prefix options to indicate it's preference
for more than one usage class.
o In the SOLICIT message include an OPTION_ORO option with the
OPTION_USAGE_CLASS option code to request prefixes from all the
classes that the DHCPv6 server can provide to this requesting
Router.
The requesting router parses the OPTION_USAGE_CLASS option in
theOPTION_IAPREFIX option area of the corresponding IA_PD Prefix
option in the ADVERTISE message. The Requesting router MUST then
include all or subset of the received class based prefix(es) in the
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REQUEST message so that it will be responsible for the prefixes
selected.
2.2.2. Delegating Router Behavior for IA_PD allocation
If the Delegating router supports class based prefix allocation by
supporting the OPTION_USAGE_CLASS option and it is configured to
assign prefixes from different classes, it selects prefixes for class
based prefix allocation in the following way:
o If requesting router includes OPTION_USAGE_CLASS within the IA_PD
Prefix option, it selects prefixes to be offered from that
specific class.
o If requesting router includes OPTION_USAGE_CLASS within
OPTION_ORO, then based on its configuration and policy it MAY
offer prefixes from multiple classes available.
The delegating router responds with an ADVERTISE message after
populating the IP_PD option with prefixes from different usage
classes. Along with including the IA_PD prefix options in the IA_PD
option, it also includes the OPTION_USAGE_CLASS option in the
OPTION_IAPREFIX option area of the corresponding IA_PD prefix option.
If neither the OPTION_ORO nor the IA_PD option in the SOLICIT message
include the OPTION_USAGE_CLASS option, then the delegating router MAY
allocate the prefix as specified in [RFC3633] without including the
class option in the IA_PD prefix option in the response.
If OPTION_ORO option in the Solicit message includes the
OPTION_USAGE_CLASS option code but the delegating router does not
support the solution described in this specification, then the
delegating router acts as specified in [RFC3633]. The requesting
router MUST in this case also fall back to the behavior specified in
[RFC3633].
If both delegating and requesting routers support class-based prefix
allocation, but the delegating router cannot offer prefixes for any
other reason, it MUST respond to requesting router with appropriate
status code as specified in [RFC3633]. For e.g., if no prefixes are
available in the specified class then the delegating router MUST
include the status code NoPrefixAvail in the response message.
2.2.3. DHCPv6 Client Behavior for IA_NA allocation
DHCPv6 client MAY request for an IA_NA address allocation from a
specific usage class in the following way:
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o In the SOLICIT message within the IA_NA option, it MAY include the
OPTION_USAGE_CLASS requesting address to be allocated from a
specific usage class indicated in that option.
If DHCPv6 client receives OPTION_USAGE_CLASS option in the IAaddr-
options area of the corresponding IA_NA but does not support this
option, it SHOULD ignore the received option.
2.2.4. DHCPv6 Server Behavior for IA_NA allocation
The DHCPv6 server parses OPTION_USAGE_CLASS option received and when
it supports allocation within the requested OPTION_USAGE_CLASS
responds with an ADVERTISE message after populating the IA_NA option
with address information from the requested Usage class. Along with
including the IA Address options in the IA_NA option, it also
includes the OPTION_USAGE_CLASS option in the corresponding IAaddr-
options area.
Even though the IA_NA option in the SOLICIT message does not include
the OPTION_USAGE_CLASS option, based on local policies, the DHCP
server MAY select a default OPTION_USAGE_CLASS value for the client
and then SHOULD include the OPTION_USAGE_CLASS option in the IAaddr-
options area of the corresponding IA_NA it sends to the client. If
both DHCP client and server support Usage-class-based address
allocation, but the DHCP server cannot offer addresses in the
specified Usage class then the DHCP server MUST include the status
code NoAddrsAvail (as defined in [RFC3315]) in the response message.
If the DHCP server cannot offer addresses for any other reason, it
MUST respond to requesting router with appropriate status code as
specified in [RFC3315].
2.3. Usage
Class based prefix delegation can be used by the requesting router to
configure itself as a DHCPv6 server to serve its DHCPv6 clients. It
can allocate longer prefixes from a delegated shorter prefix it
received, for serving IA_NA and IA_PD requests.
2.3.1. OPTION_USAGE_CLASS Values
Following values will be allocated from the IANA maintained
OPTION_USAGE_CLASS registry:
o global-anchor(1) - Prefix is globally anchored and hence would
allow mobility.
o local-breakout(2) - Prefix is managed in a local-breakout domain
and hence has limited mobility.
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o Vendor-specfied-class(3) - Prefix class is specified by the
vendor, Vendor class data in the option that follows will provide
more information.
New values of OPTION_USAGE_CLASS can be assigned and registered with
IANA as per policy detailed in section Section 5.1.
2.3.2. Class based prefix and IA_NA allocation
The requesting router can use the delegated prefix(es) from different
classes (for example "video", "guest", "voice" etc), for assigning
the IPv6 addresses to the end hosts through DHCPv6 IA_NA based on a
preconfigured mapping with OPTION_USAGE_CLASS option, the following
conditions MAY be observed:
o It MAY have a pre-configured mapping between the usage class and
OPTION_USER_CLASS option received in IA_NA.
o It MAY match the OPTION_USAGE_CLASS if the IA_NA request received
contains OPTION_USAGE_CLASS.
o It MAY have a pre-configured mapping between the usage class and
the client DUID received in DHCPv6 message.
o It MAY have a pre-configured mapping between the usage class and
its network interface on which the IA_NA request was received.
The requesting router playing the role of a DHCPv6 server can
ADVERTISE IA_NA from a class of prefix(es) thus selected.
2.3.3. Class based prefix and IA_PD allocation
If the requesting router, receives prefix(es) for different classes
(for example "video", "guest", "voice" etc), it can use these
prefix(es) for assigning the longer IPv6 prefixes to requesting
routers it serves through DHCPv6 IA_PD by assuming the role of
delegating router, its behavior is explained in Section 2.2.2.
2.3.4. Class based prefix and SLAAC
DHCPv6 IA_NA and IPv6 Stateless Address Autoconfiguration (SLAAC as
defined in [RFC4862]) are two ways by IPv6 addresses can be
dynamically assigned to end hosts. Making SLAAC class aware is
outside the scope of this document, it is specified in
[I-D.korhonen-dmm-prefix-properties].
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2.3.5. Class based Information-Request
A DHCP client MAY include OPTION_USAGE_CLASS in the Information
request message to indicate that the requested configuration
information (such as a list of available DNS servers) may be
associated with a specific Usage Class.The server responds to the
client with the requested Options whose values are determined based
on the received OPTION_USAGE_CLASS. Even though the Information
request message does not include the OPTION_USAGE_CLASS option, based
on local policies, the DHCP server MAY select a default
OPTION_USAGE_CLASS value for the client and then SHOULD include the
OPTION_USAGE_CLASS option Information Response it sends to the
client.
2.3.6. Class based prefix and applications
Applications within a host can do source address selection based on
the class of the prefix learnt in OPTION_USAGE_CLASS using rules
defined in [RFC3484].
3. Example Application
The following sub-sections provide examples of class based prefix
delegation and how it is used in a mobile network. Each of the
examples will refer to the below network:
The example network consists of :
Mobile Gateway It is network entity anchoring IP traffic in the
mobile core network. This entity allocates an IP address which is
topologically valid in the mobile network and may act as a mobility
anchor if handover between mobile and Wi-Fi is supported.
Mobile Nodes (MN) A host or router that changes its point of
attachment from one network or subnetwork to another. A mobile node
may change its location without changing its IP address; it may
continue to communicate with other Internet nodes at any location
using its (constant) IP address, assuming link-layer connectivity to
a point of attachment is available.
Access Point (AP) A wireless access point, identified by a MAC
address, providing service to the wired network for wireless nodes.
Access Router (AR) An IP router residing in an access network and
connected to one or more Acess Point(AP)s. An AR offers IP
connectivity to MNs.
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WLAN controller (WLC) The entity that provides the centralized
forwarding, routing function for the user traffic.
Example mobile network
_----_ _----_ _----_
_( )_ _( )_ _( )_
(Operator-1) (Operator-2) (Operator-3)
(_ _) (_ _) (_ _)
-+-- -+-- '-+--'
+--------+ +--------+ +--------+
| Mobile | | Mobile | | Mobile |
|gateway | |gateway | |gateway |
+--------+ +--------+ +--------+
| | |
+-------------. | .-------------+
| | |
| | |
| | |P1:"global-anchor"(1)
| | |
+--------+ _----_
+---+ | |P2:"local-breakout"(2)_( )_
|AAA|. . . . . . . | Access |---------------------( Internet )
+---+ | Aggreg |-----------+ (_ _)
| Gateway| P3:"guest"| '----'
+--------+ |
| | +----- Guest Access
| | Network
| +-------------+
| |
| +-----+
| | AR |
+-----+ +-----+
| WLC | * ---------*
| | ( LAN )
+-----+ * ---------*
/ \ / \
+----+ +----+ +----+ +----+
|WiFi| |WiFi| |WiFi| |WiFi|
| AP | | AP | | AP | | AP |
+----+ +----+ +----+ +----+
. .
/ \ / \
MN1 MN2 MN3 MN4(guest)
Figure 1
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3.1. Class based prefix delegation
The Access Aggregation Gateway requests for Prefix delegation from
Mobile gateway and associates the prefix received with usage class
"global-anchor"(1). The Access Aggregation Gateway is preconfigured
to provide prefixes from the following classes: "global-anchor" (1),
"local-breakout"(2), "guest"(x). It has a preconfigured policy to
advertise prefixes to requesting routers and mobile nodes based on
the service class supported by the service provider for the
requesting device. In the example mobile network, the Access
Router(AR) requests class based prefix allocation by sending a DHCPv6
SOLICIT message and include OPTION_USAGE_CLASS in the OPTION_ORO.
The Access Router (AR) receives an advertise with following prefixes
in the IA_PD option:
1. P1: IA_PD Prefix option with a prefix 3001::1::/64 containing
OPTION_USAGE_CLASS set to "global-anchor"(1)
2. P2: IA_PD Prefix option with a prefix 3001::2::/64 containing
OPTION_USAGE_CLASS set to "local-breakout"(2)
3. P3: IA_PD Prefix option with a prefix 3001::3::/64 containing
OPTION_USAGE_CLASS set to "guest"(x)
It sends a REQUEST message with all of above prefixes and receives a
REPLY message with prefixes allocated for each of the requested
class.
3.2. IPv6 address assignment from class based prefix
When the Access Router(AR) receives a DHCPv6 SOLICIT requesting IA_NA
from the mobile node that has mobility service enabled, it offers an
IPv6 address from the usage class "global-anchor"(1). For MN3 it
advertises 3001::1::1 as the IPv6 address in OPTION_IAADDR in
response to the IA_NA request.
The Mobile Node(MN4) Figure 1 sends a DHCPv6 SOLICIT message
requesting IA_NA address assignment with OPTION_USER_CLASS option
containing the value "guest" towards the CPE. The Access Router(AR)
assumes the role of the DHCPv6 server and sends an ADVERTISE to the
MN with OPTION_IA_NA containing an IPv6 address in OPTION_IAADDR from
the "guest" usage class. The IPv6 address in the OPTION_IAADDR is
set to 3001::3::1. The "guest" class can also be distinguished based
on a preconfigured interface or SSID advertised for MNs connecting to
it.
When the Access Aggregation Gateway receives a DHCPv6 SOLICIT
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requesting IA_NA from MNs through WLC and it has a preconfigured
profile to provide both local-breakout internet access and global-
anchor, it offers an IPv6 address from the usage class "local-
breakout" (2) and "global-anchor"(1). For MN1 it advertises
3001::2::1 and 3001::1::2 as the IPv6 address in OPTION_IAADDR in
response to the IA_NA request. Applications within MN1 can choose to
use the appropriate prefix based on the mobility enabled or local-
breakout property attached to the prefix based on source address
selection policy.
4. Acknowledgements
The authors would like to acknowledge review and guidance received
from Frank Brockners, Wojciech Dec, Richard Johnson, Erik Nordmark,
Hemant Singh, Mark Townsley, Ole Troan, Bernie Volz
5. IANA Considerations
IANA is requested to assign an option code to OPTION_USAGE_CLASS from
the "DHCPv6 and DHCPv6 options" registry (http://www.iana.org/
assignments/dhcpv6-parameters/dhcpv6-parameters.xml).
5.1. OPTION_USAGE_CLASS values
IANA is requested to reserve and maintain registry of
OPTION_USAGE_CLASS values and manage allocation of values in the
following way as per as per policy defined in [RFC5226]:
1. Values 1 to 8191 ( 0x0001 - 0x1FFF) - IETF assigned class with
IETF consensus, RFC Required policy
2. Values 8192 to 16368 (0x2000 - 0x3ff0) - Vendor defined class
assigned on a First Come First Served allocation policy
3. Values 16369 to 16383 (0x3ff1 - 0x3fff) - Experimental usage
reserved for Private Use
Following values will be allocated from this registry as explained in
section Section 2.3.1:
o global-anchor(1) - Prefix is globally anchored and hence would
allow mobility.
o local-breakout(2) - Prefix is managed in a local-breakout domain
and hence has limited mobility.
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o Vendor-specfied-class(3) - Prefix class is vendor specified.
6. Security Considerations
Security issues related to DHCPv6 which are described in section 23
of [RFC3315] and [RFC3633] apply for scenarios mentioned in this
draft as well.
7. Change History (to be removed prior to publication as an RFC)
Changes from -00 to -01
a. Modified motivation section to focus on mobile networks
b. Modified example with a mobile network and class based prefix
delegation in it
Changes from -00 to -02
a. Modified option format to be enumerated values
b. Added IANA section to request managing of registry for the
enumerated values
c. Added initial values for the class
d. Added section for applications to select address with a specific
property
8. References
8.1. Normative References
[I-D.korhonen-dmm-prefix-properties]
Korhonen, J., Patil, B., Gundavelli, S., Seite, P., and D.
Liu, "IPv6 Prefix Mobility Management Properties",
draft-korhonen-dmm-prefix-properties-02 (work in
progress), July 2012.
[IANAEnterprise]
IANA, "Private Enterprise Numbers,
http://www.iana.org/assignments/enterprise-numbers".
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
Bhandari, et al. Expires January 17, 2013 [Page 14]
Internet-Draft DHCPv6 class based prefix July 2012
[RFC2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", RFC 2460, December 1998.
[RFC2865] Rigney, C., Willens, S., Rubens, A., and W. Simpson,
"Remote Authentication Dial In User Service (RADIUS)",
RFC 2865, June 2000.
[RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C.,
and M. Carney, "Dynamic Host Configuration Protocol for
IPv6 (DHCPv6)", RFC 3315, July 2003.
[RFC3484] Draves, R., "Default Address Selection for Internet
Protocol version 6 (IPv6)", RFC 3484, February 2003.
[RFC3633] Troan, O. and R. Droms, "IPv6 Prefix Options for Dynamic
Host Configuration Protocol (DHCP) version 6", RFC 3633,
December 2003.
[RFC3775] Johnson, D., Perkins, C., and J. Arkko, "Mobility Support
in IPv6", RFC 3775, June 2004.
[RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
Address Autoconfiguration", RFC 4862, September 2007.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 5226,
May 2008.
8.2. Informative References
[RFC2629] Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629,
June 1999.
[RFC3552] Rescorla, E. and B. Korver, "Guidelines for Writing RFC
Text on Security Considerations", BCP 72, RFC 3552,
July 2003.
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Authors' Addresses
Shwetha Bhandari
Cisco Systems
Cessna Business Park, Sarjapura Marathalli Outer Ring Road
Bangalore, KARNATAKA 560 087
India
Phone:
Email: shwethab@cisco.com
Gaurav Halwasia
Cisco Systems
Cessna Business Park, Sarjapura Marathalli Outer Ring Road
Bangalore, KARNATAKA 560 087
India
Phone: +91 80 4426 1321
Email: ghalwasi@cisco.com
Sindhura Bandi
Cisco Systems
Cessna Business Park, Sarjapura Marathalli Outer Ring Road
Bangalore, KARNATAKA 560 087
India
Phone: +91 80 4426 2347
Email: sinb@cisco.com
Sri Gundavelli
Cisco Systems
170 West Tasman Drive
San Jose, CA 95134
USA
Email: sgundave@cisco.com
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Hui Deng
China Mobile
53A, Xibianmennei Ave., Xuanwu District
Beijing 100053
China
Email: denghui02@gmail.com
Laurent Thiebaut
Alcatel-Lucent
France
Email: laurent.thiebaut@alcatel-lucent.com
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