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Network Working Group Brian Bidulock
INTERNET-DRAFT OpenSS7 Corporation
February 21, 2004
Expires in August 2004
Signalling Gateway (SG) Information (SGINFO) Support
for
Signalling User Adaptation Layers
<draft-bidulock-sigtran-sginfo-04.txt>
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 or RFC 2026. Internet-Drafts are working
documents of the Internet Engineering Task Force (IETF), its areas,
and its working groups. Note that other groups may also distribute
working documents as Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six
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Copyright
Copyright (C) The Internet Society (2003). All Rights Reserved.
Abstract
This Internet-Draft describes Signalling Gateway (SG) Information
(SGINFO) for Signalling User Adaptation Protocols [M2UA..TUA], which
permits supporting Signalling Gateways (SG) to convey additional
Application Server (AS) support information to Application Server
Processes (ASPs) activating for AS on the SG. This additional AS
support information consists of information pertaining to the
underlying SS7 Signalling Provider that otherwise would have to be
statically configured at the Application Server Process (ASP) or
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exchanged between SG and ASP using a non-IETF defined protocol.
Contents
A complete table of contents, list of tables and illustrations, and
change history appears at the end of this document.
1. Introduction
1.1. Scope
This Internet-Draft provides parameters and procedures in extension
to the parameters and procedures of the Signalling User Adaptation
Layers (UAs) [M2UA..TUA], for the purpose of supporting the transfer
of SG-specific information of interest to an Application Server during
the ASP Active procedure.
UA implementations with SGINFO are intended to be compatible with
UA implementations not supporting this configuration.
1.2. Abbreviations
AS --Application Server.
ASP --Application Server Process.
IANA --Internet Assigned Numbers Authority
I-D --Internet-Draft
IETF --Internet Engineering Task Force
IP --Internet Protocol.
IPSP --IP Signalling Point.
SCCP --Signalling Connection Control Part.
SCTP --Stream Control Transmission Protocol.
SG --Signalling Gateway.
SGP --Signalling Gateway Process.
SIGTRAN --IETF Signalling Transport WG
SPP --Signalling Peer Process.
SS7 --Signalling System No. 7.
SUA --SS7 SCCP-User Adpatation Layer.
TCAP --Transaction Capabilities Application Part.
TUA --SS7 TCAP-User Adaptation Layer.
UA --User Adaptation Layer.
WG --Working Group
1.3. Terminology
SGINFO adds the following terms to the terminology presented in the
UA documents:[1]
Signalling User Adaptation Layer (UA) - one or more of the Stream
Control Transmission Protocol (SCTP) [RFC 2960] SS7 Signalling
User Adaptation Layers [M2UA..TUA] supporting ASP Management.
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1.4. Overview
There is a need to provide extensions for the Signalling User
Adaptation Layer protocols to permit a Signalling Gateway (SG) to
provide Application Server (AS) specific information pertaining to the
SG's ability to support the Application Server.
For example, the "Maximum SIF Length" of MTP3 [Q.704] is a value
that an MTP-User at an AS needs to reference to avoid sending MSU data
in excess of these MTP-PDU length restrictions. The "Maximum SIF
Length"; however, can change due to SS7 Network failures or
reconfiguration at the SG that cannot be handled purely by static
configuration information at an ASP.
Additional examples exist for SCCP [Q.711] and TCAP [Q.771] and the
need for these protocol limits at the Application Server is evidenced
by the requirements for these values in the OSI/ISO NSD [X.213]
Compliant NPI [NPI], and the OSI/ISO TSD [X.214] and the OSI/ISO ROSE
[X.219] Compliant TPI [TPI], and the ACSE [ISO 8649, ISO 8650]
compliant mOSI extensions to the XNS [XNS].
SGINFO provides parameters and procedures that allow Signalling
Gateway Processes (SGPs) to inform Application Server Processes (ASPs)
of the SG parameters, as well as provides procedures to update these
parameters in an active AS.
1.4.1. Existing Information Management
While there is a mandate to provide MIBs to support UA
configuration, the existing UA procedures[2] and MIBs make no
provisions for the management of dynamic operational information at a
Signalling Gateway that is of specific concern to a UA-User at an
Application Server (AS).
For example, if an Signalling Gateway changes an operation
parameter of necessary to a UA-User at an Application Server (AS),
such as the "Maximum SIF Length", there is no mechanism for the SG to
communicate this information to the concerned Application Server (AS).
While the existing UA procedures[2] provide for the SG giving an
indication of a "Protocol Error" or "Invalid Parameter Value" as a
result of an operational parameter being exceeded, there are no
procedures for the Application Server to discover the operational
parameters when they are dynamic.
The lack of an IETF procedure for managing operational parameter
information represents a deficiency of the existing UA procedures[2]
that detracts from interoperability between separate implementations
of SGP and ASP.
1.4.2. SGINFO Information Management
To remedy these deficiencies, SGINFO provides support for the
following:
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+ Support for an SG indicating operational parameters to an
Application Server (AS).
+ Support for an SG changing operational parameter for an active
Application Server (AS).
+ Support for interworking between SGPs supporting SGINFO and ASPs
not supporting SGINFO.
Notes for Section 1
[1] See, for example, Section 1.2 of the specific UA document
[M2UA..TUA].
[2] See, for example, Section 4 of the specific UA document
[M2UA..TUA].
2. Conventions
The keywords MUST, MUST NOT, REQUIRED, SHALL, SHALL NOT, SHOULD,
SHOULD NOT, RECOMMENDED, NOT RECOMMENDED, MAY, and OPTIONAL, when they
appear in this document, are to be interpreted as described in [RFC
2119].
3. Protocol Elements
SGINFO provides the following parameters and the messages in which
they are included in addition to the parameters of the UAs.[1]
3.1. Parameters
SGINFO provides the following parameters in addition to the
parameters defined for the UAs.[1]
3.1.1. Protocol Limits
The Protocol Limits parameter is a common parameter used in the
ASPAC ACK message to indicate the protocol data unit size limitations
presented by a Signalling Gateway to an Application Server.
The Protocol Limits parameter is formatted as follows:[2]
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Tag = 0x001b | Length |
+- - - - - - - - - - - - - - - -+- - - - - - - - - - - - - - - -+
| Maximum SDU Size |
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -+
| Optimal SDU Size (optional) |
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -+
| Maximum Connect Data Size (optional) |
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -+
| Maximum Disconnect Data Size (optional) |
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -+
| Maximum ESDU Size (optional) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Protocol Limits parameter contains the following fields:
Maximum SDU Size field: 32-bits (signed integer)
The Maximum SDU Size field contains the maximum number of bytes in
the Protocol Data parameter that the Signalling Gateway can support
to the specific Application Server.
M2UA For M2UA [M2UA] the Maximum SDU Size field provides the maximum
size of the data payload of the Protocol Data field. The
maximum size is the largest maximum data payload size that can
be transferred across the SS7 network by the SG for the
specified link. For example, for an SG supporting an SIF
Maximum Size [Q.704] of 3094 bytes on the link, this size would
be 3094. For an SG supporting 272 bytes, this size would be
272.
M3UA For M3UA [M3UA] the Maximum SDU Size field provides the limit
on the maximum size of the data payload of the Protocol Data
field. The maximum size is the largest maximum data payload
size that can be transferred across the SS7 network by the SG
for the specific Application Server. For example, for an SG
supporting both an SIF Maximum Size [Q.704] of 3094 bytes on a
primary links and 272 bytes on secondary links, this size would
be 3094.
SUA For SUA [SUA] the Maximum SDU Size field provides the limit on
the maximum size of the User Data field for a normal (non-
expedited) data transfer. The maximum size is the largest data
payload size that can be transferred across the SS7 network for
the specific Application Server (and associated Protocol Class)
considering segmentation. If there is no limit on the NSDU
size for an SCCP provider at an SG, this field will be set to a
value of -1 (0xFFFFFFFF).
TUA For TUA [TUA] the Maximum SDU Size field provide the limit on
the maximum size of the Components field for a TC-CONTINUE data
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transfer. The maximum size is the largest component size that
can be transferred across the SS7 network for the specific
Application Server (and associated Operation Class) considering
segmentation. If there is no limit on the component size for a
TCAP provider at the SG, this field will be set to a value of
-1 (0xFFFFFFFF).
Optimal SDU Size field: 32-bits (signed integer)
The Optimal SDU Size field contains the optimal number of bytes in
the Protocol Data parameter that the Signalling Gateway can support
to the specific Application Server.
M2UA For M2UA [M2UA] the Optimal SDU Size field does not apply and
is not included in the Protocol Limits parameter.
M3UA For M3UA [M3UA] the Optimal SDU Size field provides the limit
on the optimal size of the data payload of the Protocol Data
field. The optimal size is the smallest maximum data payload
size that can be transferred across the SS7 network by the SG
for the specific Application Server. For example, for an SG
supporting both an SIF Maximum Size [Q.704] of 3094 bytes on a
primary links and 272 bytes on secondary links, this size would
be 272.
SUA For SUA [SUA] the Optimal SDU Size field provides the limit on
the optimal size of the User Data field for a normal (non-
expedited) data transfer. The optimal size is the largest data
protocol size that can be transferred across the SS7 network
for the specific Application Server (and associated Protocol
Class) without segmentation.
TUA For TUA [TUA] the Optimal SDU Size field provides the limit on
the optimal size of the Components field for a TC-CONTINUE data
transfer. The optimal size is the largest component size that
can be transferred across the SS7 network for the specific
Application Server (and associated Operation Class) without
segmentation.
Maximum Connect Data Size field: 32-bits (signed integer)
The Maximum Connect Data Size field contains the maximum number of
bytes in the Data parameter that the Signalling Gateway can support
to the specific Application Server upon connection or transaction
dialogue establishment.
M2UA For M2UA [M2UA] the Maximum Connect Data Size field does not
apply and is not included in the Protocol Limits parameter.
M3UA For M3UA [M3UA] the Maximum Connect Data Size field does not
apply and is not included in the Protocol Limits parameter.
SUA For SUA [SUA] the Maximum Connect Data Size field provides a
limit on the maximum size of the User Data field that can be
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included in CORE and COAK messages. For Connection-less
operation, this field does not apply and is not included in the
Protocol Limits parameter.
TUA For TUA [TUA] the Maximum Connect Data Size field provides the
limit on the maximum size of the User Information and
Components that can be included in a TQRY or initial TCNV
message. For Operation Class 4, this field does not apply and
is not included in the Protocol Limits parameter.
Maximum Disconnect Data Size field: 32-bits (signed integer)
The Maximum Disconnect Data Size field contains the maximum number
of bytes in the Data parameter that the Signalling Gateway can
support to the specific Application Server upon disconnection or
transaction dialogue abort.
M2UA For M2UA [M2UA] the Maximum Disconnect Data Size field does not
apply and is not included in the Protocol Limits parameter.
M3UA For M3UA [M3UA] the Maximum Disconnect Data Size field does not
apply and is not included in the Protocol Limits parameter.
SUA For SUA [SUA] the Maximum Disconnect Data Size field provides a
limit on the maximum size of the User Data field that can be
included in a RELRE message. For Connection-less operation,
this field does not apply and is not included in the Protocol
Limits parameter.
TUA For TUA [TUA] the Maximum Disconnect Data Size field provides
the limit on the maximum size of the User Abort Information
that can be included in a TUAB message. For Operation Class 4,
this field does not apply and is not included in the Protocol
Limits parameter.
Maximum ESDU Size field: 32-bits (signed integer)
The Maximum ESDU Size field contains the maximum number of bytes in
the Data parameter that the Signalling Gateway can support to the
specific Application Server when data is expedited on a connection.
M2UA For M2UA [M2UA] The Maximum ESDU Size field does not apply and
is not included in the Protocol Limits parameter.
M3UA For M3UA [M3UA] the Maximum ESDU Size field does not apply and
is not included in the Protocol Limits parameter.
SUA For SUA [SUA] the Maximum ESDU Size field provides a maximum
number of bytes in the User Data field for an expedited data
transfer. The maximum size is the largest expedited data
payload size that can be transferred across the SS7 network for
the specific Application Server. For Connection-less or
Protocol Class 2 operation, this field does not apply and is
not included in the Protocol Limits parameter.
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TUA For TUA [TUA] the Maximum ESDU Size field does not apply and is
not included in the Protocol Limits parameter.
3.2. Messages
SGINFO extends the following messages defined for the UAs.[1]
3.2.1. ASP Active Acknowledgment (ASPAC ACK)
SGINFO supplements the ASPAC ACK message by permitting the
following optional parameters to be included in the message:
Extension Parameters
-----------------------------------------
Protocol Limits Optional
The format of the resulting ASP ACK message for M2UA is as
follows:[3]
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Tag = 0x000b | Length = 8 |
+- - - - - - - - - - - - - - - -+- - - - - - - - - - - - - - - -+
| Traffic Mode Type |
+-------------------------------+-------------------------------+
| Tag = 0x0001 | Length |
+- - - - - - - - - - - - - - - -+- - - - - - - - - - - - - - - -+
\ \
/ Interface Identifiers /
\ \
+-------------------------------+-------------------------------+
| Tag = 0x0008 | Length |
+- - - - - - - - - - - - - - - -+- - - - - - - - - - - - - - - -+
| Interface Identifier Start1 |
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -+
| Interface Identifier Stop1 |
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -+
| Interface Identifier Start2 |
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -+
| Interface Identifier Stop2 |
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -+
\ . \
/ . /
\ . \
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -+
| Interface Identifier StartN |
+- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -+
| Interface Identifier StopN |
+---------------------------------------------------------------+
/ /
\ Additional Interface Identifiers \
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/ of Tag Type 0x1 or 0x8 /
\ \
+-------------------------------+-------------------------------+
| Tag = 0x001b | Length |
+- - - - - - - - - - - - - - - -+- - - - - - - - - - - - - - - -+
\ \
/ Protocol Limits /
\ \
+-------------------------------+-------------------------------+
| Tag = 0x0004 | Length |
+- - - - - - - - - - - - - - - -+- - - - - - - - - - - - - - - -+
\ \
/ Info String /
\ \
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The format of the resulting ASPAC ACK message for M3UA, ISUA, SUA
and TUA is as follows:[4]
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Tag = 0x0006 | Length = 8 |
+- - - - - - - - - - - - - - - -+- - - - - - - - - - - - - - - -+
\ \
/ Routing Context /
\ \
+-------------------------------+-------------------------------+
| Tag = 0x001b | Length |
+- - - - - - - - - - - - - - - -+- - - - - - - - - - - - - - - -+
\ \
/ Protocol Limits /
\ \
+-------------------------------+-------------------------------+
| Tag = 0x0004 | Length |
+- - - - - - - - - - - - - - - -+- - - - - - - - - - - - - - - -+
\ \
/ Info String /
\ \
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
To indicate restrictions on the maximum sizes for transfer of data,
the SGP and IPSP MUST include the Protocol Limits parameter in the
ASPAC ACK message.
No other changes to the ASPAC ACK message format are provided by
this extension.
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Notes for Section 3
[1] See, for example, Section 3 of the specific UA document
[M2UA..TUA].
[2] EDITOR'S NOTE:- The parameter tag values shown as 0x001b will
be assigned by IANA within the common parameter range of the
SIGTRAN UAs and may change its value in further versions of
this document.
[3] EDITOR'S NOTE:- The parameter tag values shown as 0x001b will
be assigned by IANA within the common parameter range of the
SIGTRAN UAs and may change its value in further versions of
this document.
[4] EDITOR'S NOTE:- The parameter tag values shown as 0x001b will
be assigned by IANA within the common parameter range of the
SIGTRAN UAs and may change its value in further versions of
this document.
4. Procedures
The following procedures are provided in extension to the UA
procedures by SGINFO.
4.1. ASP Management Procedures
4.1.1. ASP Active Procedures
In extension of the "ASP Active Procedures" of the UAs[2], SGINFO
provides the following procedures:
Whenever an SGP, as a part of the normal UA procedures, sends an
ASP Active Acknowledgment (ASPAC ACK) to an ASP, it MAY include the
Protocol Limits parameter indicating the protocol data size limits
that apply to the Application Server associated with the Routing
Contexts (Interface Identifiers) specified or implied in the ASPAC ACK
message. Where the protocol limits only apply to one Application
Server, the SGP SHOULD NOT include more than one Routing Context
(Interface Identifier) in the ASPAC ACK response. That is, in
response to an ASPAC message containing multiple Routing Contexts
(Interface Identifiers), the SGP SHOULD send a separate ASPAC ACK
reply for each Routing Context (Interface Identifier) for which it
includes the Protocol Limits parameter.
If an SG discovers that the protocol data size limits has changed
due to an event, (such as a failure in the SS7 network), the SGP MAY
send an unsolicited ASPAC ACK message containing the new protocol
limits.
Whenever an ASP receives an ASPAC ACK message as part of the normal
UA procedures, or receives an unsolicited ASPAC ACK for an active
Application Server (AS), the ASP will apply the new protocol data size
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limits to the Application Server.
4.2. Interworking
Whenever an SGP receives an ERR("Invalid Parameter") message
indicating the Protocol Limits parameter in response to a sent ASPAC
ACK message containing a Protocol Limits parameter, the SGP SHOULD re-
attempt by sending the ASPAC ACK without a Protocol Limits parameter.
5. Examples
5.1. ASP and SGP both supporting Protocol Limits
An example of an ASP and SGP both supporting Protocol Limits is
illustrated in Figure 1.
As illustrated in Figure 1, the sequence of events for this example
are as follows:
(1) An Application Server at an ASP begins in the AS-DOWN or AS-
INACTIVE state.
(2) The ASP activates an Application Server by sending an ASPAC
message.
(3) The SGP responds with an ASPAC ACK message containing the
current protocol limits in the Protocol Limits parameter. The
ASP applies these protocol limits to the Application Server
upon activation.
SGP ASP
| ASPUP |
|<------------------------------|
| ASPUP ACK |
(1) |------------------------------>|
| |
| ASPAC |
(2) |<------------------------------|
| |
| ASPAC ACK(Protocol Limits) |
(3) |------------------------------>|
| |
. .
. .
. .
| ASPAC ACK(Protocol Limits) |
(4) |------------------------------>|
| |
Figure 1. ASP and SGP both supporting Protocol Limits
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(4) Later, when the SGP notes a change to protocol limits, the SGP
sends an unsolicited ASPAC ACK message containing the updated
Protocol Limits. The ASP applies these updated protocol limits
to the Application Server upon receipt.
5.2. SGP only supporting Protocol Limits
5.2.1. ASP ignores Protocol Limits
An example of an SGP only supporting Protocol Limits where the ASP
ignores the Protocol Limits parameter is illustrated in Figure 2.
As illustrated in Figure 2, the sequence of events for this example
are as follows:
(1) An Application Server at an ASP begins in the AS-DOWN or AS-
INACTIVE state.
(2) The ASP activates an Application Server by sending an ASPAC
message.
(3) The SGP responds with an ASPAC ACK message containing the
current protocol limits in the Protocol Limits parameter. The
ASP ignores the Protocol Limits parameter and, instead, relies
upon internal configuration data to determine protocol limits.
(4) Later, when the SGP notes a change to protocol limits, the SGP
sends an unsolicited ASPAC ACK message containing the updated
Protocol Limits. The ASP ignores the Protocol Limits parameter
and, instead, relies upon internal configuration data to
determine protocol limits.
SGP ASP
| ASPUP |
|<------------------------------|
| ASPUP ACK |
(1) |------------------------------>|
| |
| ASPAC |
(2) |<------------------------------|
| |
| ASPAC ACK(Protocol Limits) |
(3) |------------------------------>|
| |
. .
. .
. .
| ASPAC ACK(Protocol Limits) |
(4) |------------------------------>|
| |
Figure 2. ASP and SGP both supporting Protocol Limits
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5.2.2. ASP refuses Protocol Limits
An example of an SGP only supporting Protocol Limits where the ASP
refuses the Protocol Limits parameter is illustrated in Figure 3.
As illustrated in Figure 3, the sequence of events for this example
are as follows:
(1) An Application Server at an ASP begins in the AS-DOWN or AS-
INACTIVE state.
(2) The ASP activates an Application Server by sending an ASPAC
message.
(3) The SGP responds with an ASPAC ACK message containing the
current protocol limits in the Protocol Limits parameter.
(4) The ASP refuses the ASPAC ACK message and responds with an
ERR("Invalid Parameter") message indicating the Protocol Limits
parameter as invalid.
(5) The SGP re-attempts and sends the ASPAC ACK message without the
Protocol Limits parameter and marks the ASP as incapable of
processing protocol limits.
SGP ASP
| ASPUP |
|<------------------------------|
| ASPUP ACK |
(1) |------------------------------>|
| |
| ASPAC |
(2) |<------------------------------|
| |
| ASPAC ACK(Protocol Limits) |
(3) |------------------------------>|
| |
| ERR("Invalid Parameter") |
(4) |<------------------------------|
| |
| ASPAC ACK |
(5) |------------------------------>|
| |
. .
. .
. .
| |
(6) | |
| |
Figure 3. ASP and SGP both supporting Protocol Limits
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(6) When a subsequent change in the protocol limits at the SGP
occurs, the SGP does nothing (the ASP is marked as incapable of
handling protocol limits).
5.3. ASP only supporting Protocol Limits
An example of an ASP only supporting Protocol Limits is illustrated
in Figure 4.
As illustrated in Figure 4, the sequence of events for this example
are as follows:
(1) An Application Server at an ASP begins in the AS-DOWN or AS-
INACTIVE state.
(2) The ASP activates an Application Server by sending an ASPAC
message.
(3) The SGP responds with an ASPAC ACK message not containing the
Protocol Limits parameter.
(4) The ASP receiving the ASPAC ACK with no Protocol Limits
parameter relies upon internal configuration data to determine
protocol limits.
6. Security
SGINFO does not introduce any new security risks or considerations
that are not already inherent in the UA [M2UA..TUA] Please see the
SIGTRAN Security document [SIGSEC] for security considerations and
recommendations that are applicable to each of these UAs.
SGP ASP
| ASPUP |
|<------------------------------|
| ASPUP ACK |
(1) |------------------------------>|
| |
| ASPAC |
(2) |<------------------------------|
| |
| ASPAC ACK |
(3) |------------------------------>|
| |
| |
(4) | |
| |
Figure 4. ASP and SGP both supporting Protocol Limits
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7. IANA Considerations
7.1. Protocol Extensions
SGINFO provides an additional Protocol Limits message parameter to
the common parameter range of the SIGTRAN UAs [M2UA..TUA]:
(a) The parameter is named the Protocol Limits parameter.
(b) The structure of the Protocol Limits parameter field conforms
to the UA general TLV format and is described in detail in
Section 3.1.1.
(c) The detailed definition of each component of the Protocol
Limits parameter values is described in Section 3.1.1.
(d) This document also provides a detailed description of the
intended use of the Protocol Limits[1] parameter, and in which
messages the Protocol Limits parameter should appear, how many
times, and when.
Notes for Section 7
[1] EDITOR'S NOTE:- The Protocol Limits parameter tag value shown
throughout this document as 0x001b will be assigned by IANA
within the common parameter range of the SIGTRAN UAs and may
change its value in further versions of this document.
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0. Revision History
This section provides historical information on the changes made to
this draft. This section will be removed from the document when the
document is finalized.
0.4. Changes from Version 0.3 to Version 0.4
+ updated references, version numbers and dates.
0.3. Changes from Version 0.2 to Version 0.3
+ added list of abbreviations.
+ moved history section.
+ updated revision and dates.
+ updated references.
+ split reference section.
+ updated secuirty section.
+ moved notes to end.
0.2. Changes from Version 0.1 to Version 0.2
+ added this section,
+ updated references, release version and dates,
+ minor corrections,
+ updated postscript diagrams,
+ updated author's address.
0.1. Changes from Version 0.0 to Version 0.1
0.0. Version 0.0
0.0.0. Change Log
$Log: draft-bidulock-sigtran-sginfo-04.txt,v $
Revision 0.9.2.1 2004/03/16 07:06:25 brian
- Added older drafts in pdf and txt form.
Revision 0.8.2.1 2003/08/01 12:23:16 brian
Added abbreviations, updated format.
B. Bidulock Version 0.4 Page 16
Internet Draft UA SGINFO February 21, 2004
R. References
R.1. Normative References
[M2UA] Morneault, K., Dantu, R., Sidebottom, G., Bidulock, B. and
Heitz, J., "Signaling System 7 (SS7) Message Transfer Part 2
(MTP2) - User Adaptation Layer," RFC 3331, Internet Engineering
Task Force - Signalling Transport Working Group (September,
2002).
[M3UA] Sidebottom, G., Morneault, K. and Pastor-Balbas, J., (eds),
"Signaling System 7 (SS7) Message Transfer Part 3 (MTP3) - User
Adaptation Layer (M3UA)," RFC 3332, Internet Engineering Task
Force - Signalling Transport Working Group (September, 2002).
[SUA] Loughney, J., Sidebottom, G., Coene, L., Verwimp, G., Keller,
J. and Bidulock, B., "SS7 SCCP-User Adaptation Layer (SUA),"
draft-ietf-sigtran-sua-16.txt, Internet Engineering Task Force -
Signalling Transport Working Group (December 11, 2003). Work In
Progress.
[ISUA] Bidulock, B., "SS7 ISUP-User Adaptation Layer (ISUA)," <draft-
bidulock-sigtran-isua-02.txt>, Internet Engineering Task Force -
Signalling Transport Working Group (February 21, 2004). Work In
Progress.
[TUA] Bidulock, B., "SS7 TCAP-User Adaptation Layer (TUA)," <draft-
bidulock-sigtran-tua-03.txt>, Internet Engineering Task Force -
Signalling Transport Working Group (February 21, 2004). Work In
Progress.
[RFC 2960] Stewart, R., Xie, Q., Morneault, K., Sharp, C.,
Schwarzbauer, H. J., Taylor, T., Rytina, I., Kalla, H., Zhang, L.
and Paxson, V., "Stream Control Transmission Protocol (SCTP),"
RFC 2960, The Internet Society (February 2000).
[RFC 2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels," RFC 2119 - BCP 14, The Internet Society
(March 1997).
[SIGSEC] Loughney, J., Tuexen, M. and Pastor-Balbas, J., "Security
Considerations for SIGTRAN Protocols," <draft-ietf-sigtran-
security-03.txt>, Internet Engineering Task Force - Signalling
Transport Working Group (June 29, 2003). Work In Progress.
R.2. Informative References
[Q.704] ITU, "Message Transfer Part - Signalling Network Functions
and Messages," ITU-T Recommendation Q.704, ITU-T
Telecommunication Standardization Sector of ITU, Geneva (March
1993). (Previously "CCITT Recommendation")
[Q.711] ITU, "Functional Description of Signalling Connection Control
B. Bidulock Version 0.4 Page 17
Internet Draft UA SGINFO February 21, 2004
Part," ITU-T Recommendation Q.711, ITU-T Telecommunication
Standardization Sector of ITU, Geneva (March 1993). (Previously
"CCITT Recommendation")
[Q.771] ITU, "Signalling System No. 7 - Functional Description of
Transaction Capabilities," ITU-T Recommendation Q.771, ITU-T
Telecommunication Standardization Sector of ITU, Geneva (March
1993). (Previously "CCITT Recommendation")
[X.213] ITU, "OSI - Network Service Definition," ITU-T Recommendation
X.213 (ISO/IEC 8072), ITU-T Telecommunication Standardization
Sector of ITU, Geneva (November, 1995). (Previously "CCITT
Recommendation")
[NPI] International, UNIX., "Network Provider Interface
Specification," NPI Revision 2.0.0, UNIX International
Publication, Parsippany, New Jersey (August 17, 1992).
http://www.openss7.org/doc/npi.pdf
[X.214] ITU, "Transport Service Definitions for Open Systems
Interconnection (OSI) for CCITT Applications," ITU-T
Recommendation X.214 (ISO/IEC 8072), ITU-T Telecommunication
Standardization Sector of ITU, Geneva (November, 1995).
(Previously "CCITT Recommendation")
[X.219] ITU, "Information processing systems - Text Communication,
Remote Operations: Model, Notation and Service Definition," ITU-T
Recommendation X.219 (ISO/IEC 9072-1), ITU-T Telecommunication
Standardization Sector of ITU, Geneva (n.d.). (Previously "CCITT
Recommendation")
[TPI] Open Group, "Transport Provider Interface Specification," TPI
Version 2, Draft 2, Open Group Publication (1999).
http://www.opengroup.org/onlinepubs/
[ISO 8649] International Standards Organization, "Information
Processing Systems - Open Systems Interconnection - Service
Definition for the Association Control Service Element," ISO
8649:1988, International Standards Organization (1988).
[ISO 8650] International Standards Organization, "Information
Processing Systems - Open Systems Interconnection - Protocol
Specification for the Association Control Service Element," ISO
8650:1988, International Standards Organization (1988).
[XNS] Open Group, "Technical Standard: Network Services (XNS)," XNS
Issue 5.2 Draft 2.0 [ISBN: 1-85912-241-8], Open Group Publication
(1999). http://www.opengroup.org/onlinepubs/
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Author's Addresses
Brian Bidulock Phone: +1-780-490-1141
OpenSS7 Corporation Email: [email protected]
1469 Jeffreys Crescent URL: http//www.openss7.org/
Edmonton, AB T6L 6T1
Canada
This draft expires August 2004.
B. Bidulock Version 0.4 Page 19
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List of Illustrations
Figure 1. ASP and SGP both supporting Protocol Limits ........... 11
Figure 2. ASP and SGP both supporting Protocol Limits ........... 12
Figure 3. ASP and SGP both supporting Protocol Limits ........... 13
Figure 4. ASP and SGP both supporting Protocol Limits ........... 14
Table of Contents
Status of this Memo ............................................. 1
Copyright ....................................................... 1
Abstract ........................................................ 1
Contents ........................................................ 2
1 Introduction .................................................. 2
1.1 Scope ....................................................... 2
1.2 Abbreviations ............................................... 2
1.3 Terminology ................................................. 2
1.4 Overview .................................................... 3
1.4.1 Existing Information Management ........................... 3
1.4.2 SGINFO Information Management ............................. 3
Notes for Section 1 ............................................. 4
2 Conventions ................................................... 4
3 Protocol Elements ............................................. 4
3.1 Parameters .................................................. 4
3.1.1 Protocol Limits ........................................... 4
3.2 Messages .................................................... 8
3.2.1 ASP Active Acknowledgment (ASPAC ACK) ..................... 8
Notes for Section 3 ............................................. 10
4 Procedures .................................................... 10
4.1 ASP Management Procedures ................................... 10
4.1.1 ASP Active Procedures ..................................... 10
4.2 Interworking ................................................ 11
5 Examples ...................................................... 11
5.1 ASP and SGP both supporting Protocol Limits ................. 11
5.2 SGP only supporting Protocol Limits ......................... 12
5.2.1 ASP ignores Protocol Limits ............................... 12
5.2.2 ASP refuses Protocol Limits ............................... 13
5.3 ASP only supporting Protocol Limits ......................... 14
6 Security ...................................................... 14
7 IANA Considerations ........................................... 15
7.1 Protocol Extensions ......................................... 15
Notes for Section 7 ............................................. 15
0 Revision History .............................................. 16
0.4 Changes from Version 0.3 to Version 0.4 ..................... 16
0.3 Changes from Version 0.2 to Version 0.3 ..................... 16
0.2 Changes from Version 0.1 to Version 0.2 ..................... 16
0.1 Changes from Version 0.0 to Version 0.1 ..................... 16
0.0 Version 0.0 ................................................. 16
0.0.0 Change Log ................................................ 16
R References .................................................... 17
R.1 Normative References ........................................ 17
R.2 Informative References ...................................... 17
Author's Addresses .............................................. 19
B. Bidulock Version 0.4 Page 20
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List of Illustrations ........................................... 20
Table of Contents ............................................... 20
B. Bidulock Version 0.4 Page 21
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Full Copyright Statement
Copyright (C) The Internet Society (2003). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published and
distributed, in whole or in part, without restriction of any kind,
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included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of developing
Internet standards in which case the procedure for copyrights defined
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translate into languages other than English.
The limited permission granted above are perpetual and will not be
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TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT
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Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
B. Bidulock Version 0.4 Page 22
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