Router Advertisement Prefix Option Extension for On-Demand MobilityIntelHillsboroUSAwu-chix.feng@intel.comIntelPetah TikvaIsraeldanny.moses@intel.comDMM Working Group Router Advertisement / Router Solicitation is one of the ways for hosts to
establish network IPv6 connectivity configuration. This document describes
an extension to the router advertisement prefix information option to
allow the router to specify mobility service type availability to
mobile hosts. Mobile hosts can then configure their IP address
to the preferred type of mobile connectivity.
defines different
types of mobility related network services provided by access network to
mobile hosts. In particular, it defines different types of prefix continuity
types as mobile nodes move between different points of attachments.
This document defines extensions to the prefix information option
in the router advertisement message ()
to allow the router to convey mobility services associated with an
Ipv6 prefix.
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 .IP prefixes are conveyed in Router Advertisement messages through the
Prefix Information Option field ().
These prefix information option fields are used to allow
hosts to configure their IPv6 addresses. For distributed mobility management, there is a need
for a network to be able to convey different prefixes for different
connectivity scenarios.
defines different
service continuity requirements including: Non-Persistent, Session-Lasting,
Fixed, and Graceful-replacement. Currently, however, there is no
way for a router to specify the continuity type through a router
advertisement message. This document proposes modifying the prefix information option
within the router advertisement message to include mobility service
options that it is offering to mobile hosts that are attached. The modified prefix information option fields are shown
in the following figure: Fields:34
8-bit unsigned integer. The number of leading bits in the Prefix
that are valid. The value ranges from 0 to 128.
1-bit on-link flag. When set, indicates that this prefix can
be used for on-link determination. 1-bit autonomous address-configuration
flag. When set indicates that this prefix can be used for
stateless address configuration.
3-bit unused field. It MUST be initialized to zero
by the sender and MUST be ignored by the receiver.
3-bit field that specifies the service type. The field can have the following values: a non-persistent IP prefix (1)a session-lasting IP prefix (2)a fixed IP prefix (3)a graceful-replacement IP prefix (4)The definition of these service types is available in
.0 is reserved and should not be used. All other values (5-7) are reserved for future use. The value of the Service Type indicates the type of continuity service
committed by the network for the associated IPv6 prefix. Once an IPv6 prefix type is provided, any subsequent messages involving
this prefix (lease renewal - for example) must include the IPv6 Continuity
Service option with the same service type that was assigned by the server
during the initial allocation.Given the lsit of IPv6 prefixes and their associated mobility service
type, the mobile host can then configure its IP address to the appropriate
service required by the application Mobile hosts that do not support this new option should ignore the prefix information option. Routers should also send an additional prefix information
option without the session-type field from time to time
for hosts that do not support this new format.
There are no specific security considerations for this option.TBD