IKEv2 Mobility and Multihoming U. Schilcher
(mobike) Universitaet Klagenfurt
Internet-Draft H. Tschofenig
Expires: September 6, 2006 F. Muenz
Siemens AG
S. Sugimoto
Ericsson
March 5, 2006
Application Programming Interface to a Trigger Database for MOBIKE
draft-schilcher-mobike-trigger-api-03.txt
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Copyright Notice
Copyright (C) The Internet Society (2006).
Abstract
MOBIKE is a protocol which adds mobility and multihome support for
IKEv2. MOBIKE peers continuously exchange a list of available IP
addresses each other. A MOBIKE peer should have some information
about the status of each address and interface in order to execute
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the respective actions. Examples may comprise switching from one
address or interface to another. This information, which will be
referred as trigger, is distributed over a number of protocol daemons
at an end host. To make this information available to a MOBIKE
daemon, it is necessary to store it centrally at the host (called
trigger database) and to enable the protocols to insert the triggers
and to allow MOBIKE to obtain timely information.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Trigger Database and MIH . . . . . . . . . . . . . . . . . . . 6
4. Trigger Classification . . . . . . . . . . . . . . . . . . . . 8
5. API for the Trigger Database . . . . . . . . . . . . . . . . . 10
6. Supported Message Types . . . . . . . . . . . . . . . . . . . 12
7. Payload Format . . . . . . . . . . . . . . . . . . . . . . . . 17
8. Applicability . . . . . . . . . . . . . . . . . . . . . . . . 22
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 23
10. Security Considerations . . . . . . . . . . . . . . . . . . . 24
11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 25
12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 26
12.1. Normative References . . . . . . . . . . . . . . . . . . 26
12.2. Informative References . . . . . . . . . . . . . . . . . 26
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 27
Intellectual Property and Copyright Statements . . . . . . . . . . 28
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1. Introduction
When a MOBIKE daemon [1] is started it first has to build a set of
all available addresses (or a subset of them for policy reasons; see
[4]) before communicating with another peer. From these addresses,
it has to select one of the addresses as the preferred address that
will be used as the source address in the communication with the
MOBIKE peer.
This address set together with the preferred address may change
during operation because of several reasons, e.g. an interface is
disconnected, a handover between two different link layer
technologies takes place or the communication path becomes
unavailable due to router failure. Many of the events, which cause
the change of the address set, are out of the scope of the MOBIKE
protocol itself but need an interaction with other protocols daemons
locally at the end host.
In order to make MOBIKE working properly, it is really important to
know about the status of the available addresses for making
reasonable decisions. A number of other protocols running on the end
host might have various information necessary to determine whether to
switch from one preferred address to another or whether it is
necessary to modify the peer address set.
An example is the IEEE 802.21 Media Independent Handover (MIH)
standard [5], which is currently under development. The MIH is
defined as a shim layer in the mobility-management protocol stack of
both, the mobile node and the network elements, that provide mobility
support. The MIH Function provides abstracted services to higher
layers about the status and performance of any link layer technology.
To benefit from this information on higher layers, however, the MIH
services must be combined with information from upper layers in order
to facilitate a basis for decisions above network layer.
In this document, we therefore suggest to define an API that allows
protocol daemons to insert information (triggers) about addresses and
interfaces into a "database" that can later be made available to the
MOBIKE daemon (or other protocols). Although, there have been some
mechanisms [6][7] that can fulfill some of these requirements, we
still need a flexible framework that can handle asynchronous event
that takes place at L3 or below, including MIH events. The API will
provide similar services to the MOBIKE daemon like MIH does for layer
3 and above. It is based on the BSD routing socket API in a similar
fashion as PF_KEY [2] extends the same API for generic key management
usage.
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This document therefore heavily focuses on the functionality offered
by the PF_KEY specification and uses the MIH Function as an example
for retrieving necessary information for a decision making process.
Please note that the authors use the term 'database' in a symbolic
way. It is a container for storing information about events.
Information about the status of interfaces and addresses might not
even be stored directly in this database and could well be
implemented using a collection of pointers to the respective
information.
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2. Terminology
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 [3].
Additionally, the following terms are introduced:
o Trigger: Information which is relevant for MOBIKE about an
address.
o Trigger Database (TDB): Collection of triggers which can be
accessed via the API defined in this document.
o Media Independent Handover (MIH): Described in IEEE draft 802.21
[5] which is currently under development. The MIH Function
provides abstracted services to higher layers about the status and
performance of any link layer technology.
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3. Trigger Database and MIH
The following section should give a brief overview for the
interaction of Media Independent Handover (MIH) with Trigger Database
(TDB) and MOBIKE daemon. The services of MIH are used e.g. for
compiling relevant information about interface performance, which is
then signalled through the Trigger Database to the MOBIKE daemon.
Based on this data, the MOBIKE daemon may select a new preferred
address or continues using the current one.
+--------------------------------------+
| MOBIKE daemon |
| +-------------------+ |
| | PF_TRIGGER socket | |
| +--------------+----+ |
| ^ | |
+-----------|-----------|--------------+
| |
| |
TDB TDB
Events Commands
| |
| v
+-----------+--------------------------+
| Trigger Database (TDB) |
| (Layer 3 an above) |
+--------------------------------------+
^ | ^
| | |
MIH MIH Information
Events Commands Service
| | |
| v v
+--------------------------------------+
| Media Independent Handover Function |
+--------------------------------------+
^ | ^
| | |
Link Link Information
Events Commands Service
| | |
| v v
+--------------------------------------+
| Lower Layers (Layer 2 and below) |
+--------------------------------------+
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To receive event notifications from the MIH, the Trigger Database
must perform two steps:
Capability discovery:
While the MIH provides many services, not all of them may be
supported on a given platform. For learning, which of them are
actually supported, the Trigger Database must query the MIH with a
"MIH_Capability_Discover.request". The response, a
"MIH_Capability_Discover.response" message will then indicate with
a bit mask which services are supported. Alternatives and
solutions for not supported but required services is done in a
future version of this draft.
Service registration:
Now knowing the supported services, the Trigger Database must
register to the services it is interested in with a
"MIH_Event_Register.request" message. To confirm registration,
the MIH answers with a "MIH_Event_Register.confirm" message and
notifies the Trigger Database in case of status change of
interfaces.
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4. Trigger Classification
Many different events may cause a change in the address set used by
MOBIKE (see [4]). These events can be issued by many different
protocols running in kernel or user space. Since the reaction (if
any) on a given event depends on the type of the event, a
classification of these events is necessary.
As an example, we define the following triggers in this document:
Trigger type Value Description
---------------------------+-------+-------------------------------
TDB_TTYPE_IF_ADDED | 1 | New interface added
TDB_TTYPE_IF_REMOVED | 2 | Interface removed
TDB_TTYPE_IF_REMOVEDSOON | 3 | Interface is expected to be
| | removed soon
TDB_TTYPE_IF_ADDRADDED | 4 | New address added to interface
TDB_TTYPE_IF_ADDRREMOVED | 5 | Address removed from interface
TDB_TTYPE_IF_ADDRCHANGED | 6 | Interface has changed one of its
| | addresses (e.g. new DHCP lease)
TDB_TTYPE_TUNNEL_ADDED | 7 | IPSec tunnel was established
TDB_TTYPE_TUNNEL_CHANGED | 8 | IPSec tunnel conf. changed
TDB_TTYPE_TUNNEL_REMOVED | 9 | IPSec tunnel was removed
TDB_TTYPE_CONN_ESTABLISHED | 10 | e.g. dial-in network
| | has connected
TDB_TTYPE_CONN_LOST | 11 | connection to network lost
TDB_TTYPE_DEST_UNREACHABLE | 12 | e.g. ICMP packet received
TDB_TTYPE_MAX | 13 | Maximum value for trigger types
The types TDB_TTYPE_TUNNEL_ADDED, TDB_TTYPE_TUNNEL_CHANGED and
TDB_TTYPE_TUNNEL_REMOVED are inspired by [8]. Any listed trigger
types will be signalled using the "tdb_trigger" message structure
described in Section 7
Details about the supported message types and their formats can be
found below:
TDB_TTYPE_IF_ADDED:
This message is signalled if a new interface comes up and directly
refers to the "Link_Up.indication" event notification of the MIH
Function.
TDB_TTYPE_IF_REMOVED:
This message is signalled if an interface is going down and
directly refers to the "Link_Down.indication" event notification
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of the MIH Function.
TDB_TTYPE_IF_REMOVEDSOON:
This message is signalled if an interface is expected (predicted)
to go down within a certain time interval and directly refers to
the "Link_Going_Down.indication" event notification of the MIH
Function.
A future version of this document will add more triggers and a more
detailed description of them.
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5. API for the Trigger Database
To access the trigger database, an API is defined. For that purpose
the new network protocol family ID PF_TRIGGER has to be defined. The
operation of the API is analogue to the PF_KEY interface (see [2]).
To access the API, a socket of the family PF_TRIGGER has to be
created. To communicate with the Trigger Database, messages are sent
and received through the socket with the send() and recv() functions.
Any other functions like bind(), connect(), etc. are not supported
and MUST NOT have any effects on a socket of the PF_TRIGGER family.
The following exhibits a sample socket creation:
int s = socket(PF_TRIGGER, SOCK_RAW, PF_TRIGGER);
The format of the messages is the following: Each message starts with
a fixed header. Appended to this header, there are some payloads
depending on the type of the message. The available message types
are described in Section 6.
Each time when a message is sent to the Trigger Database, it will
respond with a message of the same type. This response contains the
same payloads as transmitted to the Trigger Database, only some
additional information MAY be included (e.g., the Trigger Database
assigns an id to each trigger).
The normal operation works in the following way: A MOBIKE
implementation, which wants to be informed about changes in the
Trigger Database, registers itself to the Trigger Database by sending
a TDB_REGISTER message.
If a protocol daemon wants to add, delete or modify an existing
trigger it sends a TDB_ADD, TDB_DELETE or TDB_MODIFY message
respectively to the Trigger Database including information that is
important to add, delete or modify the trigger.
The Trigger Database acknowledges this message with a TDB_ADD,
TDB_DELETE or TDB_MODIFY response to the network protocol and with a
TDB_NOTIFY message to the registered MOBIKE implementation. This
notify message contains information about the newly added, deleted or
modified trigger including its ID. All available information about a
trigger can be requested with a TDB_GET message.
If a MOBIKE implementation no longer wants to receive notifications
for changes to the Trigger Database, it sends a TDB_DEREGISTER
message.
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In a future version of this document, we will try to add some
information about scenarios to better illustrate the interaction.
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6. Supported Message Types
Several different message types can be sent to the Trigger Database
using a PF_TRIGGER socket. The message type is indicated by the
tdb_header_msgtype field that is part of the generic message header
(see Section 7) and can be one of the following values:
Message type Value Description
------------------+---------+------------------------------
TDB_ADD | 1 | Add a trigger to the
| | Trigger Database
TDB_GET | 2 | Get information about an
| | existing trigger.
TDB_DELETE | 3 | Delete a trigger from the
| | Trigger Database
TDB_REGISTER | 4 | Registers an application
| | to receive messages for
| | each new trigger added.
TDB_DEREGISTER | 5 | Deregisters an application
| | from receiving messages for
| | each new trigger added.
TDB_NOTIFY | 6 | A new trigger has been
| | added, deleted or updated.
TDB_MODIFY | 7 | Modify a trigger in the
| | Trigger Database
TDB_DUMP | 8 | Dump all Trigger Database
| | entries
TDB_FLUSH | 9 | Delete all Trigger Database
| | entries
TDB_MAX | 10 | Generic maximum for message
| | types
Each message type requires different payloads to be appended. Each
payload starts with a generic payload header followed by payload
specific data. The generic header has the following structure:
struct tdb_payload {
uint16_t tdb_payload_len;
uint16_t tdb_payload_type;
} __attribute__( ( packed ) );
/* sizeof( struct tdb_payload ) == 4 */
The tdb_payload_len field contains the length of the payload divided
by 8. The type of the payload is determined by the tdb_payload_type
field, which contains one of the following values:
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Payload type Value Description
---------------------------+---------+-------------------------------
TDB_PT_INTERFACE | 1 | Information about an interface
TDB_PT_ADDRESS | 2 | The IP address of an interface
TDB_PT_TRIGGER | 3 | Trigger id, type, etc.
Details about the supported message types and their formats can be
found below:
TDB_ADD:
If an application or network protocol wants to add a new trigger,
it sends a TDB_ADD message to the Trigger Database. The new
trigger is stored in the Trigger Database and a corresponding
TDB_NOTIFY message that indicates that a new trigger has been
added is sent to all registered applications.
The format of the message is:
<HEADER, TRIGGER, INTERFACE, [ADDRESS]>
The TRIGGER payload indicates the type of the trigger and also
includes some trigger specific data. The INTERFACE payload is
needed to select the appropriate physical interface, the new
trigger is related to. For many triggers, an additional address
payload is required. It contains, for example, the new address
for a TDB_TTYPE_IF_ADDRCHANGED trigger.
The response from the Trigger Database contains the same
information as the request:
<HEADER, TRIGGER, INTERFACE, [ADDRESS]>
TDB_DELETE:
A trigger, which is stored inside the Trigger Database, can be
deleted using the TDB_DELETE payload. In the request the only
information, which has to be specified is the id of the trigger,
which is stored in 'TRIGGER(*)'. A corresponding TDB_NOTIFY
message that indicates that a trigger has been deleted is sent to
all registered applications.
The format of the message is:
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<HEADER, TRIGGER(*)>
The Trigger Database responds with a message with the following
format:
<HEADER, TRIGGER>
In the response, the TRIGGER payload has all fields filled with
the correct values.
TDB_GET:
The TDB_GET message is used to request all available information
of a specified trigger. In the request the only information,
which has to be specified is the id of the trigger, which is
stored in 'TRIGGER(*)'.
The format of the message is:
<HEADER, TRIGGER(*)>
The Trigger Database responds with a message of the following
format:
<HEADER, TRIGGER, INTERFACE, [ADDRESS]>
In the response a fully initialized TRIGGER payload is present.
Additionally, INTERFACE payload is present as well as and an
optional an ADDRESS payload, if an address is available for the
specified trigger.
TDB_REGISTER:
An application, which is interested in each new trigger, can
register itself to the Trigger Database. After the application
has registered, it receives a message each time a new trigger has
been added to the database. The format of the message is:
<HEADER>
No additional payload has to be added. The Trigger Database
responds with a message of the same type and with the same
content, i.e. its format is:
<HEADER>
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TDB_DEREGISTER:
An application, which is no longer interested in receiving
notifications about trigger changes, can de-register itself from
the Trigger Database. The format of the message is:
<HEADER>
No additional payload has to be added. The Trigger Database
responds with a message of the same type and with the same
content, i.e. its format is:
<HEADER>
TDB_NOTIFY
An application that has registered itself to get informed about
the new triggers or updates to these triggers, receives a
TDB_NOTIFY message. The format of the message is the same as for
a TDB_ADD message. The only difference is that some field are
filled by the Trigger Database before sending the TDB_NOTIFY
message.
The format of the message is:
<HEADER, TRIGGER, [INTERFACE], [ADDRESS]>
Since this message is sent by the Trigger Database itself, a
registered application MUST NOT respond to it.
TDB_MODIFY:
If an application or a network protocol wants to modify a trigger
(because its status has changed), it sends a TDB_MODIFY message to
the Trigger Database. The new trigger is stored and a
corresponding TDB_NOTIFY message that indicates that an existing
trigger has been modified is sent to all registered applications.
The format of the message is:
<HEADER, TRIGGER, [INTERFACE], [ADDRESS]>
The TRIGGER payload indicates the type of the trigger and also
includes some trigger specific data.
The response from the Trigger Database contains the same
information as the request:
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<HEADER, TRIGGER, [INTERFACE], [ADDRESS]>
TDB_DUMP:
An application, that wants to learn all currently available
triggers should send a TDB_DUMP message. Since a TDB_GET message
requires a specific trigger id for retrieval, applications which
to not know all trigger IDs depend on this message class for
learning all unknown triggers. The format of the message is:
<HEADER>
The Trigger Database will respond with all currently available
triggers entries by serially sending the following message:
<HEADER, TRIGGER, INTERFACE, [ADDRESS]>
TDB_FLUSH:
For deleting all entries in a Trigger Database, the TDB_FLUSH
message is used. Since the TDB_GET message requires a specific
trigger id for deletion, reliable cleaning of a Trigger Database
can be done with this message. The format of the message is:
<HEADER>
The Trigger Database will respond with the following message:
<HEADER>
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7. Payload Format
HEADER:
Each message starts with the fixed header. It contains general
information about the message and determines, which payloads have
to be included in it. It has the following format:
struct tdb_header {
uint8_t tdb_header_version;
uint8_t tdb_header_msgtype;
uint8_t tdb_header_errno;
uint8_t tdb_header_reserved1;
uint16_t tdb_header_msglen;
uint16_t tdb_header_reserved2;
uint32_t tdb_header_seq;
uint32_t tdb_header_pid;
} __attribute__( ( packed ) );
/* sizeof( struct tdb_header ) == 16 */
The fields of this structure contain the following values:
tdb_header_version: The version of the used PF_TRIGGER interface.
This document specifies this API in version 1.
tdb_header_msgtype: This field contains the type of the message.
All possible values are listed in the table in Section 6.
tdb_header_errno: If an error occurred while processing a request,
the response will only include the message header without any
payloads. The type of the error is indicated by the value in
this field. The values are taken from the error number
specification of the operating system (e.g. the errno.h file).
tdb_header_msglen: The length of the message divided by 8 is
stored into this field.
tdb_header_seq: This field contains the number of the last message
sent incremented by 1.
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tdb_header_pid: The process id of the program sending the message.
If the message is generated inside the kernel, this value is
set to zero.
INTERFACE:
The INTERFACE payload is used to provide all needed information
about an active network interface.
The format of the INTERFACE payload is the following:
struct tdb_interface {
uint16_t tdb_interface_len;
uint16_t tdb_interface_pltype;
uint32_t tdb_interface_selector;
uint32_t tdb_interface_type;
uint32_t tdb_interface_bandwidth;
uint32_t tdb_interface_quality;
uint32_t tdb_interface_reserved;
} __attribute__( ( packed ) );
/* sizeof( struct tdb_interface ) == 16 */
This fields contain the following values:
tdb_interface_len: This field contains the length of the payload
divided by 8.
tdb_interface_pltype: This field contains the value
TDB_PT_INTERFACE.
tdb_interface_selector: The tdb_interface_selector field stores
interface enumeration information for unique identification (IF
#0, #1, #2, ...). When a new interface comes up, this value
should be set by the kernel.
tdb_interface_type: Classification of an interface, for instance
fixed or wireless network link. The MIH Function provides this
information by issuing a "MIH_Poll.request" from the Trigger
Database, before creating any event notification destined for
the MOBIKE daemon.
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tdb_interface_bandwidth: Information about the maximum bandwidth
of an interface. The MIH Function provides this information by
issuing a "MIH_Poll.request" from the Trigger Database, before
creating any event notification destined for the MOBIKE daemon.
tdb_interface_quality: Information about current connection
quality of an interface. The MIH Function provides this
information by issuing a "MIH_Poll.request" from the Trigger
Database, before creating any event notification destined for
the MOBIKE daemon.
tdb_interface_reserved: This field is reserved for future use and
MUST be set to zero.
Further information about an interface might be necessary.
Especially asymmetric link connectivity/availability in case of
wireless connections might be relevant. This is left for future
investigation.
ADDRESS:
The ADDRESS payload is used to provide the IP address of an
interface to the Trigger Database or registered application. This
information is important for most triggers. But it might be
possible that there are trigger types which do not need an ADDRESS
payload.
The format of the ADDRESS payload is:
struct tdb_address {
uint16_t tdb_address_len;
uint16_t tdb_address_pltype;
uint8_t tdb_address_proto;
uint8_t tdb_address_prefixlen;
uint16_t tdb_address_reserved;
} __attribute__( ( packed ) );
/* sizeof( struct tdb_address ) == 8 */
/* followed by some form of struct sockaddr */
Information about IP address and probably ports is provided by a
sockaddr structure which is attached to the tdb_address structure.
A sockaddr structure is capable of storing both a IPv4 and IPv6
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address. The fields of the tdb_address structure contains the
following values:
tdb_address_len: This field contains the length of the payload
including the sockaddr structure divided by 8.
tdb_address_pltype: The tdb_address_pltype field contains the
value TDB_PT_ADDRESS.
tdb_address_proto: The tdb_address_proto field is normally set to
zero. However, if is are set in the attached sockaddr needed,
then the field SHOULD be set to the protocol number of the
upper layer protocol. (e.g. TCP or UDP). This functionality
may become relevant for signalling IPSec related information
(e.g. tunnel changes)
tdb_address_prefixlen: This field contains the prefix length of
the address, which might be useful to key management
applications, which employ it in access control decisions. If
the tdb_address_prefixlen is non-zero the address has a prefix.
tdb_address_reserved: The tdb_address_reserved field is reserved
for future use and MUST be set to zero.
TRIGGER:
The TRIGGER payload is used to provide all needed information
about a trigger itself, e.g. the trigger type, an id, etc. The
notation TRIGGER(*) indicates that only the id field is used to
identify the trigger and all other fields SHOULD be set to zero.
The format of the TRIGGER payload is the following:
struct tdb_trigger {
uint16_t tdb_trigger_len;
uint16_t tdb_trigger_pltype;
uint16_t tdb_trigger_type;
uint16_t tdb_trigger_reserved1;
uint32_t tdb_trigger_id;
uint32_t tdb_trigger_reserved2;
} __attribute__( ( packed ) );
/* sizeof( struct tdb_trigger ) == 16 */
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This fields contain the following values:
tdb_address_len: This field contains the length of the payload
divided by 8.
tdb_address_pltype: This field contains the value TDB_PT_TRIGGER.
tdb_address_type: The type of the trigger is stored into this
field. All possible values are listed in the table in section
Section 4.
tdb_address_id: The id of a trigger is assigned by the Trigger
Database itself. In the message sent by userspace programs,
which do not know this value (e.g. for TDB_ADD messages), this
value MUST be set to zero.
Further information about a trigger might be necessary. This is
left for future investigation.
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8. Applicability
Even though this document is intended to give a solution for MOBIKE,
the API is generic enough to make information available for other
protocols as well.
The Next Step In Signaling (NSIS) protocol suite, for example,
requires access to up-to-date information about IP addresses,
interfaces and interactions with mobility protocols. In order to
react on mobility events some sort of interaction between the kernel,
various signalling protocols (including Mobile IP, IKE/IPsec, etc.)
and the NSIS daemon is required (see [9]). Hence, an NSIS daemon
supporting mobility could benefit from a generic interface to meet
it's requirements for fast and accurate detection of mobility events,
address and interface changes. GIMPS, for example, demands immediate
reaction in case of a mobility event (e.g., handover). Monitoring
procedures of mobility management protocols like Mobile IP are
required to react to these mobility events in an appropriate way.
The trigger database and it's API could provide necessary information
for detecting such a movement (new interface/IP address available,
expiring Mobile IP timers).
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9. IANA Considerations
This document defines an IANA registry for the protocol family
PF_TRIGGER.
An IANA registry might be needed for the different trigger types (for
which examples are provided in Section 4).
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10. Security Considerations
This document describes an API which allows information about IP
addresses to be obtained at a local host. A malicious application or
protocol daemon could disseminate wrong information. This would make
other protocols, such as MOBIKE, believe that the status of a
particular address has changed. This will likely lead to unexpected
protocol behaviour, such as switching between addresses back-and-
forth. Hence, a certain trust has to be placed into the applications
and protocol daemons that are allowed to access the database to
insert, modify or delete triggers. Access control mechanisms might
enforce certain rights to use the API or parts of it.
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11. Acknowledgments
The authors would like to thank Murugaraj Shanmugam, Yu Xinwen,
Wolfgang Groeting and Stefan Berg for their comments. Furthermore,
the authors would like to thank Emanuel Corthay for pointing them to
the IEEE 802.21 draft.
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12. References
12.1. Normative References
[1] Eronen, P., "IKEv2 Mobility and Multihoming Protocol (MOBIKE)",
draft-ietf-mobike-protocol-08 (work in progress), February 2006.
[2] McDonald, D., Metz, C., and B. Phan, "PF_KEY Key Management API,
Version 2", RFC 2367, July 1998.
[3] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", March 1997.
12.2. Informative References
[4] Kivinen, T. and H. Tschofenig, "Design of the MOBIKE Protocol",
draft-ietf-mobike-design-08 (work in progress), March 2006.
[5] Rajkumar, Ajay., Williams, Michael., Liu, Xiaoyu., and Vivek.
Gupta, "Media Independent Handover Services", IEEE-Draft Draft
IEEE Standard for Local and Metropolitan Area Networks / IEEE
P802.21/D00.01, July 2005.
[6] Sklower, K., "Tree-based Packet Routing Table for Berkeley
UNIXProceedings of the Winter 1991 USENIX Conference, Dallas,
TX, USENIX Association. 1991. pp. 93-103.", 1991.
[7] Salim, J., Khosravi, H., Kleen, A., and A. Kuznetsov, "Linux
Netlink as an IP Services Protocol", RFC 3549, July 2003.
[8] Sugimoto, S. and F. Dupont, "PF_KEY Extension as an Interface
between Mobile IPv6 and IPsec/IKE",
draft-sugimoto-mip6-pfkey-migrate-01 (work in progress),
August 2005.
[9] Lee, S., Jeong, S., Tschofenig, H., Fu, X., and J. Manner,
"Applicability Statement of NSIS Protocols in Mobile
Environments",
draft-ietf-nsis-applicability-mobility-signalling-02 (work in
progress), July 2005.
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Authors' Addresses
Udo Schilcher
Universitaet Klagenfurt
Klagenfurt, Carinthia 9020
Austria
Email: udo.schilcher@edu.uni-klu.ac.at
Hannes Tschofenig
Siemens
Otto-Hahn-Ring 6
Munich, Bayern 81739
Germany
Email: Hannes.Tschofenig@siemens.com
Franz Muenz
Siemens AG
Otto-Hahn-Ring 6
Munich, Bayern 81739
Germany
Email: Franz.Muenz@thirdwave.de
Shinta Sugimoto
Ericsson Research Japan
Nippon Ericsson K.K.
Koraku Mori Building
1-4-14, Koraku, Bunkyo-ku
Tokyo 112-0004
Japan
Phone: +81 3 3830 2241
Email: shinta.sugimoto@ericsson.com
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