Mobile IP Working Group H. Haverinen
J. Malinen
Internet Draft Nokia
June 2000
Mobile IP Regional Paging
draft-haverinen-mobileip-reg-paging-00.txt
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
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This document is an individual submission for the mobile-ip Working
Group of the Internet Engineering Task Force (IETF). Comments
should be submitted to the MOBILE-IP@STANDARDS.NORTELNETWORKS.COM
mailing list.
Distribution of this memo is unlimited.
Abstract
This document specifies Mobile IP Regional Paging (MIRP), a small
and link-layer independent extension to Mobile IP [2] with regional
registrations [3], to support power-constrained operation in the
mobile nodes and to reduce routing state information in the visited
domain. The extension allows a mobile node to enter a power saving
idle mode during which its location is known with the coarse
accuracy defined by a paging area. Downlink routes to idle mobile
nodes terminate in a paging foreign agent, which re-establishes them
on demand by means of paging. This does not require snooping of data
packets but is a natural extension to network-level routing.
Optionally, the mobile node and the visited domain can agree on
communication time slots used for Agent Advertisements and paging,
to restrict link interface power-on time in the mobile node.
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Table of Contents
Status of this Memo.........................................1
Abstract....................................................1
Table of Contents...........................................2
1. Introduction.............................................2
2. Terms....................................................3
3. Protocol Operation.......................................5
3.1. Paging Area Discovery..................................5
3.2. Entering Idle Mode.....................................6
3.3. Paging.................................................7
3.4. Entering Active Mode...................................8
4. Protocol Extensions......................................9
4.1. Advertisement Interval Extension.......................9
4.2. Paging Area ID Extension..............................10
4.3. Idle Mode Request Extension...........................10
4.4. Idle Mode Reply Extension.............................11
4.5. Paging Request Message................................12
4.6. Paged Mobile Node Address Extension...................14
5. IANA Considerations.....................................14
6. Security Considerations.................................15
7. IPv6 Considerations.....................................15
8. Intellectual Property Right Notice......................15
9. References..............................................15
Authors' Addresses.........................................16
1. Introduction
This document specifies an extension to Mobile IP [2] with regional
registrations [3] in order to support power-constrained operation
and to reduce routing state information in the visited domain. The
extension allows a mobile node to enter a power saving idle mode.
The visited domain does not know the location of idle mobile nodes
with the accuracy of an IP subnetwork but with a more coarse
accuracy of a paging area.
Foreign agents advertise paging support by including a Paging Area
ID extension in the Agent Advertisements. A mobile node that wishes
to enter the idle mode sends either a Registration Request or a
Regional Registration Request with an Idle Mode Request extension to
the paging foreign agent of the current paging area. The paging
foreign agent includes an Idle Mode Reply extension to the
corresponding Registration Reply or Regional Registration Reply. In
the idle mode, the mobile node does not need to perform subsequent
registrations when it moves between the IP subnetworks of the paging
area.
The mobile node enters the active mode by performing a normal home
registration or a normal regional registration. The network may
trigger this by paging the mobile node. The network pages the mobile
node by sending an Agent Advertisement with a Paged Mobile Node
Address extension to a paging multicast address.
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When entering the idle mode, the mobile may optionally negotiate
time slot based paging to be used. In this case, the mobile node and
the network agree on the time slots used for Agent Advertisement and
paging within the paging area.
2. Terms
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 [4].
This document uses the same terminology as [2]. In addition, this
document frequently uses the following terms:
Active Mode
When a mobile node is in the active mode, it operates as normally
with regional registrations. In order to send or receive packets,
the mobile node must be in the active mode.
Advertisement Interval
The time between two successive unsolicited Agent Advertisements,
in milliseconds.
Advertisement Slot
A time slot during which an idle mobile node activates its
receiver to be able to receive the periodical unsolicited Agent
Advertisements sent by the leaf foreign agents in the paging
area.
Crossover Foreign Agent
When a mobile node is performing a Regional Registration, the
crossover foreign agent is the foreign agent where the old path
of tunnels leading to a mobile node and the new path cross, i.e.
the foreign agent in the hierarchy where a change in the
tunneling or routing information is needed in order to keep the
communication path to the mobile node up-to-date.
Idle Mode
When a mobile node is in the idle mode, the network knows its
location with a smaller precision than usual, in a granularity
defined by the paging area. In the idle mode, the mobile node may
be able to deactivate some of its components for energy-saving
purposes.
Idle Mobile Node
A mobile node that is in the idle mode.
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Idle Mode Registration
A home registration or regional registration performed by a
mobile node in order to enter the idle mode or to extend the
lifetime of a previous idle mode registration. A mobile node
performs an idle mode registration by sending either a
Registration Request or a Regional Registration Request with an
Idle Mode Request extension.
Leaf Foreign Agent
A foreign agent in a regional mobility hierarchy closest to the
mobile node. This is usually a leaf of a tree structure of
foreign agents within the visited domain.
Paging Agent Advertisement
An Agent Advertisement which is sent to a paging multicast
address and which contains a Paged Mobile Mode Address extension.
Paging Area
An area containing possibly multiple foreign agents where an idle
mobile node can be without the visited domain knowing anything
more precise about the location of the idle mobile node. The
foreign agent at the root of the paging area is called a paging
foreign agent.
Paging Foreign Agent
The foreign agent that maintains the paging state in a paging
area. The downlink communication paths to idle mobile nodes
within this paging area terminate in this foreign agent. In the
foreign agents closer to the mobile node in the hierarchy, that
is, below this node, there is no need to maintain any
communication state information for idle mobile nodes.
Paging Multicast Address
An IP multicast address used for paging a mobile node by leaf
foreign agents. When a mobile node is paged, each leaf foreign
agent sends an Agent Advertisement to this address with the Paged
Mobile Node Address extension indicating which mobile node is
being paged. Such advertisements are called paging Agent
Advertisements. A paging multicast address can be used for paging
one or more mobile nodes.
Paging Slot
A time slot during which an idle mobile node activates its
receiver to be able to receive the possible paging Agent
Advertisements sent by the leaf foreign agents in the paging
area.
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Visited Domain
The domain defined by a hierarchy of regional-aware foreign
agents. This domain is usually administered by a single entity
and can have secure localized signaling between the foreign
agents in the domain. When the mobile node stays inside one
visited domain (and the home registration does not expire), the
mobile node does not need to do home registrations but can use
the regional registrations to get a fast response from the
localized location management.
3. Protocol Operation
3.1. Paging Area Discovery
A leaf foreign agent advertises paging support with the Paging Area
ID extension in the Agent Advertisement. The mobile node detects its
current paging area based on the paging area ID. If the Agent
Advertisement contains an FA NAI extension [3], the mobile node uses
the pair (paging area ID, the realm part of the FA NAI) as an
identifier for the paging area. A mobile node considers two foreign
agents to belong to the same paging area only if the foreign agents
advertise the same paging area ID, and either both the foreign
agents advertise the FA NAI with the same realm part or neither of
the foreign agents advertise the FA NAI.
When an idle mobile node detects that it has moved to a new paging
area, it MUST perform either a normal home registration, a normal
regional registration or an idle mode registration.
The visited domain can contain anything from zero to as many paging
areas as there are foreign agents in a visited domain. However, the
subtree of a paging foreign agent MUST belong to the same paging
area.
The advertisement MAY also contain an Advertisement Interval
extension which specifies the time interval between subsequent
advertisements. An Advertisement Interval extension with non-zero
slot length field indicates support for time slot based paging
within the paging area. In the time slot based paging case, the leaf
foreign agents of the paging area send Agent Advertisements
simultaneously with the same advertisement interval.
A new field in the Advertisement Interval extension indicates the
length of the advertisement slot in milliseconds. The advertisement
slot is the time during which idle mobile nodes power on their
receivers in order to receive unsolicited Agent Advertisements. This
allows foreign agents with overlapping cells to send their
advertisements at slightly different times in order to avoid
interference. Because foreign agents may send their advertisements
at slightly different times, mobile nodes cannot determine the exact
instant of the advertisement slot. Therefore, foreign agents do not
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send unsolicited Agent Advertisements during first and the last
quarter of the advertisement slot.
Slot sequence number is another new field in the Advertisement
Interval extension that is used for determining the mobile node's
paging slot as described in Section 3.2.
If time-slot based paging is used, the paging area is assumed to
have a mechanism for synchronizing the clocks of the foreign agents.
Such a mechanism is beyond the scope of this document.
If time slot based paging is used, a mobile node that is in the idle
mode MAY power on its receiver when an unsolicited Agent
Advertisement or a paging Agent Advertisement is expected and keep
its receiver powered off at other times. The mobile node doesn't
have to power on its receiver for every advertisement slot, but it
MAY power on its receiver only for every Nth advertisement slot,
where N can be freely picked by the mobile node. If the mobile node
does not receive an Agent Advertisement during the advertisement
slot, whether due to leaving the paging area or due to clock skew,
it SHOULD send an Agent Solicitation and keep its receiver powered
on until it receives an Agent Advertisement.
3.2. Entering Idle Mode
When the mobile node is sending or receiving data packets, it is in
the active mode. When the mobile node is in the active mode, the
operation is exactly the same as in Mobile IP with regional
registrations. When the mobile node is not actively communicating,
it can enter the idle mode. When the mobile node is in the idle
mode, the visited domain does not know the exact location of the
mobile node. The visited domain only knows the paging area of the
idle mobile node.
When the mobile node wishes to enter the idle mode, it performs an
idle mode registration by sending either a Registration Request or a
Regional Registration Request with an Idle Mode Request extension.
If time slot based paging is used, the Idle Mode Request extension
contains the paging slot interval expressed as a multiple of
advertisement intervals.
When the paging foreign agent receives the Registration Request or
the Regional Registration Request with an Idle Mode Request
extension, it adds the mobile node to the visitor list and marks its
mode as idle. The entry in the visitor list is otherwise maintained
as normal entries in regional registrations, but the paging foreign
agent does not have any tunnels or other routing information for the
mobile node in its routing table. As any registration, the idle mode
registration has a lifetime. A mobile node that wishes to stay in
the idle mode longer than this lifetime must extend the lifetime by
performing another idle mode registration. The mobile node may also
extend the lifetime of its home registration and yet stay in the
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idle mode by performing a home registration with the Idle Mode
Request extension.
The operation of the paging foreign agent upon receipt of a data
packet destined to an idle mobile node is specified in Section 3.3.
The foreign agents closer to the mobile node in the hierarchy do not
need to maintain any state specific to the mobile node. That is,
after forwarding the message containing the Idle Mode Reply
extension to the mobile node, these foreign agents delete the mobile
node from their visitor lists. If the idle mode registration is a
regional registration and the crossover foreign agent is above the
paging foreign agent in the hierarchy, it also receives the Regional
Registration Request and updates its state as normally in regional
registrations.
The paging foreign agent includes an Idle Mode Reply extension to
the Registration Reply or the Regional Registration Reply. The reply
contains a paging multicast address. The leaf foreign agents of the
paging area use this address for paging the mobile node when they
receive a Paging Request from a paging foreign agent.
If the optional time slot based paging mechanism is used, the Idle
Mode Reply extension contains a paging slot index (an integer) and a
paging slot offset (milliseconds). The paging slot instant is
determined as follows. The paging slot is N milliseconds later than
the advertisement slot for which the slot sequence number of the
Agent Advertisement modulo the paging slot interval is equal to
zero. The delay N equals paging slot index times advertisement
interval plus paging slot offset. In other words, the paging slot
interval specifies how often a paging slot occurs, and the paging
slot index and the paging slot offset specify when the paging slots
occur in relation to unsolicited Agent Advertisements. For example,
if paging slot interval is four, paging slot index is two and paging
slot offset is 100 ms, then there is a paging slot 100 ms after
every fourth advertisement slot. More specifically, the paging slot
is 100 ms after the advertisement slots for which slot sequence
number modulo four equals two.
The length of the paging slot is equal to the length of the
advertisement slot. Since mobile nodes cannot determine the exact
instant of the paging slot, foreign agents do not send paging Agent
Advertisements during first and the last quarter of the paging slot.
The sequence number field in the Agent Advertisement cannot be used
in determining the paging slot because the foreign agent increments
the sequence number also in solicited Agent Advertisements. Thus the
new slot sequence number field is required.
3.3. Paging
When the paging foreign agent receives a packet from a correspondent
node destined to a mobile node that has the idle flag set, the
paging foreign agent does not forward the packet to any lower
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foreign agent. Instead, the paging foreign agent sends a Paging
Request to its child foreign agents which forward the message to
their child foreign agents recursively. The leaf foreign agents send
a paging Agent Advertisement to the mobile node using the paging
multicast address. This advertisement contains a Paged Mobile Node
Address extension which identifies the target among the mobile nodes
listening to this paging multicast address. When time slot based
paging is supported, the Paging Request contains the paging slot
interval, the paging slot index, and the paging slot offset.
The leaf foreign agents send the paging Agent Advertisement with a
Paged Mobile Node Address extension to the mobile node's paging
multicast address. Besides the Paged Mobile Node Address extension,
the leaf foreign agent includes the same extensions that it normally
includes in solicited Agent Advertisements.
If time slot based paging is used, the leaf foreign agents send the
paging Agent Advertisement during the second or the third quarter of
the mobile node's paging slot.
The mobile node is expected to perform an ordinary home registration
or an ordinary regional registration in response to a paging Agent
Advertisement. The paging foreign agent MAY retransmit the Paging
Request after a timeout. If the mobile node has not performed a
regional registration after a small number of retransmissions, the
paging foreign agent SHOULD send a Destination Unreachable ICMP
message to the correspondent node.
While waiting for the response of the mobile node, the paging
foreign agent MAY buffer the data destined to the mobile node. When
the mobile node has entered the active mode, the paging foreign
agent can stop buffering and forward the buffered packets to the
mobile node. The paging foreign agent discards buffered packets
after a timeout.
3.4. Entering Active Mode
When the mobile node receives an Agent Advertisement to its paging
multicast address and the advertisement contains the address of the
mobile node in the Idle Mobile Node Address extension, the mobile
node enters the active mode. The mobile node can also enter the
active mode if it needs to send a packet.
When entering the active mode, the mobile node sends a Registration
Request or a Regional Registration Request. This changes the state
of the visited domain as defined in the regional registrations [3].
This registration clears the idle mode in the paging foreign agent
and allows all subsequent data to reach the mobile node.
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4. Protocol Extensions
4.1. Advertisement Interval Extension
Mobile IPv6 [5] defines an Advertisement Interval option, used in
Router Advertisement messages to advertise the interval at which the
sending router sends unsolicited multicast Router Advertisements.
The regional paging support uses the format of this option in a
skippable extension to the unsolicited IPv4 Agent Advertisement,
with an additional slot length field. Foreign agents do not include
the Advertisement Interval extension in solicited Agent
Advertisements. The format of the Advertisement Interval extension
is as follows:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Slot Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Advertisement Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| (Slot Sequence Number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type
TBD (skippable)
Length
8-bit unsigned integer. The length of the option, excluding the
type and length fields, in octets. The value of this field MUST
be 6.
Slot Length
16-bit unsigned integer. Indicates the length, in milliseconds,
of the advertisement slot during which the mobile nodes activate
their receivers in order to receive unsolicited Agent
Advertisements, if time slot based paging is supported. Because
non-zero slot length is useful only when paging is supported, the
Agent Advertisement MUST also include a Paging Area ID extension
if the slot length is non-zero. If the slot length field is zero,
it indicates that the Paging Area does not support time slot
based paging.
The slot length also specifies the length of the paging slot
within the paging area.
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Advertisement Interval
32-bit unsigned integer. The time, in milliseconds, between
successive unsolicited router Agent Advertisement messages sent
by this foreign agent on this network interface. Note that unlike
in the original Mobile IPv6 Advertisement Interval Option, the
Advertisement Interval field in this extension specifies the
exact interval, not the maximum interval.
Slot Sequence Number
An optional field that contains a 16-bit unsigned integer. This
field is included if time slot based paging is supported. The
slot sequence number in each unsolicited Agent Advertisement is
one greater than in the previous unsolicited Agent Advertisement.
All the foreign agents in a paging area must advertise the same
slot sequence number. The slot sequence number is used for
determining mobile nodes' paging slot, as specified in Section
3.2.Paging Area ID Extension
The Paging Area ID extension is defined as follows:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Paging Area ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type
TBD (skippable)
Length
The length (in octets) of the Paging Area ID field.
Paging Area ID
A 16-bit identifier.The foreign agent that supports regional
paging indicates the support by including the Paging Area ID
extension in the Agent Advertisement message. If present, the Paging
Area ID extension MUST appear in the Agent Advertisement message
after any of the advertisement extensions defined in [6].
4.3. Idle Mode Request Extension
The Idle Mode Request extension is defined as follows:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | (Paging Slot Interval) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type
TBD (non-skippable)
Length
The length of the fields excluding the Type and the Length
fields, in octets. If the mobile node requests time slot based
paging, the length equals to 2, else the length equals to zero.
Paging Slot Interval
An optional field that contains a 16-bit unsigned integer. If the
mobile node requests time slot based paging, the paging slot
interval is used for determining the mobile node's paging slot,
as specified in Section 3.2.
4.4. Idle Mode Reply Extension
The Idle Mode Reply extension is defined as follows:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Paging Multicast Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| (Paging Slot Index) | (Paging Slot Offset) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type
TBD (non-skippable)
Length
The length of the fields excluding the Type and the Length
fields, in octets. If time slot based paging is used, the length
equals to 10, else the length equals to 6.
Reserved
This field is unused. It MUST be initialized to zero by the
sender and MUST be ignored by the receiver.
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Paging Multicast Address
An IP address used for paging the mobile node. If a correspondent
node sends a datagram to the mobile node while the mobile node is
in the idle mode, the network pages the mobile node by sending a
paging Agent Advertisement to this multicast address. The paging
foreign agent can decide how to assign these addresses.
Paging Slot Index
An optional field that contains a 16-bit unsigned integer. If
time slot based paging is supported, the paging slot index is
used for determining the mobile node's paging slot, as specified
in Section 3.2.
Paging Slot Offset
An optional field that contains a 16-bit unsigned integer. If
time slot based paging is supported, the paging slot offset is
used for determining the mobile node's paging slot, as specified
in Section 3.2.
4.5. Paging Request Message
When paging a mobile node, the paging foreign agent sends a Paging
Request Message to its descendants in the paging area. The
recipients of this message that have active interfaces capable of
serving mobile nodes then send a paging Agent Advertisement to those
interfaces in order to page the mobile node.
The Paging Request message is an UDP packet sent to the UDP Port
434. The Paging Request message contains the addresses of the paged
mobile nodes and optionally parameters for calculating the point of
time when to page the mobile node.
IP fields:
Source Address: Typically the interface address from which the
message is sent.
Destination Address: The address of lower foreign agent.
UDP fields:
Source Port: variable
Destination Port: 434
The UDP header is followed by Paging Request fields shown below:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Reserved | Paging Slot Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Paging Slot Index | Paging Slot Offset |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Paging Multicast Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Paged Mobile Node Addresses.. |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Paging Request fields can be followed by a Foreign-Foreign
Authentication extension.
Type
TBD
Reserved
This field is unused. It MUST be initialized to zero by the
sender and MUST be ignored by the receiver.
Paging Slot Interval
16-bit unsigned integer. The interval between two successive
paging slots, in multiples of advertisement intervals. If time
slot based paging is not used, this field must be set to zero.
Paging Slot Index
16-bit unsigned integer. A parameter used for determining the
mobile node's paging slot, as specified in Section 3.2. If time
slot based paging is not used, this field must be set to zero.
Paging Slot Offset
16-bit unsigned integer. A parameter used for determining the
mobile node's paging slot, as specified in Section 3.2. If time
slot based paging is not used, this field must be set to zero.
Paging Multicast Address
An IP multicast address used for paging the mobile node. In the
idle mode the mobile node listens to this address for the agent
advertisements which indicate paging of the mobile node by the
network.
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Paged Mobile Node Addresses
The IP home address of the mobile node that is the target of
paging. For efficiency reasons, there MAY be more than one mobile
node addresses listed in this field.
4.6. Paged Mobile Node Address Extension
The Paged Mobile Node Address extension is used for the identifying
the mobile node that is paged with the paging Agent Advertisement.
This allows several mobile nodes to share a paging multicast
address. The motivation for using an Agent advertisement for paging
is that in order to return to the active mode by performing a home
registration or a regional registration, the mobile node needs an
Agent Advertisement anyway.
The Paged Mobile Node Address extension is defined as follows:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Paged Mobile Node Addresses.. |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type
TBD (skippable)
Length
The length of the fields excluding the Type and the Length
fields, in octets.
Reserved
This field is unused. It MUST be initialized to zero by the
sender and MUST be ignored by the receiver.
Paged Mobile Node Addresses
The IP home address of the mobile node that is the target of
paging. For efficiency reasons, there MAY be more than one mobile
node addresses listed in this field.
5. IANA Considerations
MIRP requires a new Mobile IP Message type to be used for sending
the Paging Request message to the UDP port 434 (Section 4.5).
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MIRP requires three new extension types to be used in combination
with the Agent Advertisement: a skippable type for Advertisement
Interval extension (Section 4.1), a skippable type for the Paging
Area ID extension (Section 4.2), and a skippable type for the Paged
Mobile Node Address extension (Section 4.6).
MIRP requires two new extension types to be used in combination with
the Registration Request or Reply: a non-skippable type for the Idle
Mode Request extension and a non-skippable type for Idle Mode Reply
extension (Sections 4.3 and 4.4, respectively).
6. Security Considerations
MIRP uses the same security mechanisms as regional registrations
[3]. More specifically, the Idle Mode registration is protected by
the Mobile-Foreign Authentication extension using the same key
distribution and replay protection mechanisms as specified for the
regional registrations. The Paging Request message is protected by
the FA-FA Authentication extension [3].
7. IPv6 Considerations
Several proposals with regional registrations support for IPv6 are
currently under development. The mechanisms are likely to be similar
to regional registrations for IPv4. The mechanisms specified here
for Mobile IPv4 should be easily applicable to IPv6.
8. Intellectual Property Right Notice
Nokia may or may not have patents or patent applications that are
applicable for this contribution. In case such patents exist or are
subsequently granted, Nokia is willing to grant licenses on these
patents on terms according to RFC 2026, section 10.
9. References
[1] Bradner, S., "The Internet Standards Process -- Revision 3",
BCP 9, RFC 2026, October 1996.
[2] C. Perkins, Editor. "IP Mobility Support". RFC 2002bis,
March 2000.
[3] C. Perkins, E. Gustafsson, and A. Jonsson. "Mobile IP Regional
Registrations". Internet draft (work in progress), draft-ietf-
mobileip-reg-tunnel-02.txt, March 2000.
[4] S. Bradner. "Key words for use in RFCs to indicate
Requirement Levels". RFC 2119, March 1997.
Haverinen and Malinen Expires December 2000 [Page 15]
Internet Draft Mobile IP Regional Paging June 2000
[5] C. Perkins and D. B. Johnson. "Mobility Support in IPv6",
draft-ietf-mobileip-ipv6-13.txt, May 2000. (work in
progress).
[6] Charles E. Perkins and Pat R. Calhoun. AAA registration keys
for Mobile IP. draft-ietf-mobileip-aaa-key-00.txt, June 1999.
(work in progress).
Authors' Addresses
Henry Haverinen
Nokia Mobile Phones
P.O. Box 88
FIN-33721 Tampere
Finland
email: henry.haverinen@nokia.com
phone: +358 50 594 4899
fax: +358 3 318 3690
Jari T. Malinen
Nokia Research Center
Itamerenkatu 11-13
FIN-00180 Helsinki
Finland
email: jari.t.malinen@nokia.com
phone: +358 40 7499 138
fax: +358 9 4376 6852
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