Dialogic DSI M3UA Operating and maintenance manual

March 2017
U02STN
www.dialogic.com
Dialogic®DSI Protocol Stacks
M3UA Programmer's Manual

2
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Publication Date: March 2017
Document Number: U02STN

Dialogic®DSI Protocol Stacks M3UA Programmer's Manual Issue 11
3
Revision History
Issue
Date
Description
11
24-Mar-17
Route status message updates, load share update
addition of message 0x62b6 M3U_MSG_R_SERV_ASSOC_LIST
Update to M3U_MSG_R_ROUTE_STATUS
10
16-Dec-14
Addition of new measurements messages:
0x62b2 M3U_MSG_R_GL_STATS Read global traffic statistics
0x62b3 M3U_MSG_R_LK_STATS Read association traffic statistics
0x62b4 M3U_MSG_R_GL_PEAK_USAGE Read global peak usage statistics
0x62b5 M3U_MSG_R_LK_PEAK_USAGE Read association peak usage statistics
9
26-Jun-13
Addition of Routing Key Management
Addition of new licenses for 8, 256, 384, 512 & 768 link equivalents.
8
19-Apr-12
Addition of Multiple LAS support
7
30-Mar-12
Addition of 8-bit SLS rotation option and Daud_cong timer.
6
15-Jul-10
Heartbeats and SNMP added
5
01-Feb-10
Addition sections added to General Description discussing association activation,
throughput monitoring and load sharing.
4
11-Nov-09
Updates to support Automatic ASP and AS Activation
Added new message definitions:
M3U_MSG_ACTIVATE
M3U_MSG_DEACTIVATE
M3U_MSG_CNF_TIMERS
MNG_MSG_THR_ALARM
MTP_MSG_UPDATE_L4
3
25-Jun-09
Updated to include M3UA IPSP additions and DAUD operation.
General updates to message formats.
Update options in M3U_MSG_CONFIG (0x72c0)
Added new parameter to M3U_MSG_CNF_NC (0x72c4)
2
19-Jun-03
Branding changed and description of module expanded.
1
28-Jun-02
Initial Release
Note: The current version of this guide can be found at:
http://www.dialogic.com/support/helpweb/signaling

Contents
4
Contents
1Introduction ........................................................................................................7
1.1 Feature Overview ................................................................................................................... 7
1.2 Related Documentation ........................................................................................................... 8
1.3 Abbreviations ......................................................................................................................... 8
2General Description .............................................................................................9
2.1 Module Overview .................................................................................................................... 9
2.1.1 ASP and IPSP Operation .............................................................................................. 9
2.2 Module Configuration .............................................................................................................. 9
2.3 System Activation................................................................................................................... 9
2.4 Throughput Monitoring .......................................................................................................... 10
2.4.1 Read current rate and read peak rate. ........................................................................ 11
2.4.2 Notification when license limit exceeded...................................................................... 11
2.4.3 Notification when 80% of license limit exceeded........................................................... 11
2.5 Load Sharing........................................................................................................................ 12
2.6 Dual Resilient Systems .......................................................................................................... 12
3Configuration Model ..........................................................................................13
3.1 System Configuration............................................................................................................ 13
3.2 Local Application Server ........................................................................................................ 13
3.3 Association .......................................................................................................................... 13
3.4 Server................................................................................................................................. 14
3.5 Routes ................................................................................................................................ 14
3.6 Connecting via Signaling Gateways ......................................................................................... 14
3.6.1 System Configuration................................................................................................ 15
3.6.2 Association Configuration .......................................................................................... 15
3.6.3 Server Relationship Configuration............................................................................... 15
3.6.4 Route Configuration.................................................................................................. 16
3.7 Connecting directly to Peer Applications................................................................................... 16
3.7.1 System Configuration................................................................................................ 17
3.7.2 Association Configuration .......................................................................................... 17
3.7.3 Server Relationship Configuration............................................................................... 17
4Interface to system services .............................................................................19
4.1 System Functions ................................................................................................................. 19
4.2 Timer Operation ................................................................................................................... 19
5External Message Definitions: SCTP ..................................................................20
6Message Reference............................................................................................21
6.1 User Interface ...................................................................................................................... 21
6.1.1 API_MSG_TX_REQ.................................................................................................... 21
6.1.2 API_MSG_RX_IND .................................................................................................... 22
6.1.3 MTP_MSG_PAUSE..................................................................................................... 23
6.1.4 MTP_MSG_RESUME .................................................................................................. 24
6.1.5 MTP_MSG_STATUS................................................................................................... 25
6.2 Management Interface .......................................................................................................... 26
6.2.1 ASP UP Request ....................................................................................................... 26
6.2.2 ASP DOWN Request.................................................................................................. 27
6.2.3 ASP ACT Request ..................................................................................................... 28
6.2.4 ASP INACT Request .................................................................................................. 30
6.2.5 SS7 Signaling Network Management Event Request...................................................... 32
6.2.6 SS7 Network Congestion State................................................................................... 34
6.2.7 Activate Association.................................................................................................. 36
6.2.8 Deactivate Association .............................................................................................. 37
6.2.9 M3U_MSG_ACTIVATE Request ................................................................................... 38
6.2.10 M3U_MSG_DEACTIVATE Request ............................................................................... 38
6.2.11 ASP UP Indication..................................................................................................... 39
6.2.12 ASP UP Confirmation................................................................................................. 39

Dialogic®DSI Protocol Stacks M3UA Programmer's Manual Issue 11
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6.2.13 ASP DOWN Indication ............................................................................................... 40
6.2.14 ASP DOWN Confirmation ........................................................................................... 41
6.2.15 ASP ACT Indication ................................................................................................... 42
6.2.16 ASP ACT Confirmation ............................................................................................... 44
6.2.17 ASP INACT Indication................................................................................................ 46
6.2.18 ASP INACT Confirmation............................................................................................ 47
6.2.19 AS ACT Indication..................................................................................................... 48
6.2.20 AS INACT Indication.................................................................................................. 50
6.2.21 Association Status Indication ..................................................................................... 51
6.2.22 Route Status Indication ............................................................................................. 52
6.2.23 Routing Key Registration Indication ............................................................................ 54
6.2.24 RK Deregistration Indication ...................................................................................... 55
6.3 Non-primitive Interface.......................................................................................................... 57
6.3.1 Configure M3UA Module............................................................................................. 58
6.3.2 Configure M3UA Association....................................................................................... 60
6.3.3 Configure LAS-Server Relationship.............................................................................. 62
6.3.4 Configure M3UA Route .............................................................................................. 65
6.3.5 Configure Network Context ........................................................................................ 66
6.3.6 Configure Routing Key............................................................................................... 68
6.3.7 Add Server to an Association...................................................................................... 70
6.3.8 Add Route to a Server............................................................................................... 72
6.3.9 Map Network Context to Network Appearance .............................................................. 73
6.3.10 M3UA Timer Configuration Message ............................................................................ 74
6.3.11 Remove M3UA Association ......................................................................................... 75
6.3.12 Remove LAS-Server Relationship................................................................................ 76
6.3.13 Remove M3UA Route................................................................................................. 76
6.3.14 Remove Network Context .......................................................................................... 77
6.3.15 Remove Routing Key................................................................................................. 77
6.3.16 Remove Server from an Association ............................................................................ 78
6.3.17 Remove Route from a Server ..................................................................................... 79
6.3.18 Remove Network Context to Network Appearance Mapping............................................ 80
6.3.19 Read Global Traffic Statistics...................................................................................... 81
6.3.20 Read Association Traffic Statistics ............................................................................... 82
6.3.21 Read Global Peak Usage Statistics .............................................................................. 83
6.3.22 Read Association Peak Usage Statistics ....................................................................... 85
6.3.23 Read Association Statistics......................................................................................... 87
6.3.24 Read Server Statistics ............................................................................................... 91
6.3.25 Read Route Statistics ................................................................................................ 92
6.3.26 Trace Mask Configuration Request .............................................................................. 93
6.3.27 M3UA Application Server Process Status ...................................................................... 96
6.3.28 M3UA Server Status.................................................................................................. 97
6.3.29 M3UA Route Status................................................................................................... 99
6.3.30 Read LAS-Server Association List.............................................................................. 101
6.3.31 M3UA Error Indication ............................................................................................. 102
6.3.32 M3UA Event Indication ............................................................................................ 106
6.3.33 M3UA Notify Indication............................................................................................ 111
6.3.34 M3UA Audit Destination Indication ............................................................................ 113
6.3.35 MTP Update Level 4 Request .................................................................................... 114
7Example Message Sequence ............................................................................ 115
Appendix A. Message Types .....................................................................................116
A.1 Message Type Table ............................................................................................................ 116
Appendix B. Additional Services...............................................................................118
B.1 Licensing ........................................................................................................................... 118
B.1.1 Request Licensing State .......................................................................................... 118
B.1.2 License Event Indication .......................................................................................... 120
B.1.3 Request Throughput Statistics.................................................................................. 122
B.1.4 Throughput Alarm Set............................................................................................. 124

Contents
6
Figures
Figure 1: Connecting via SGs ........................................................................................................... 15
Figure 2: Connecting to Peer Applications without Signaling Gateways .................................................. 17
Figure 3: Message Sequence for a single SG and ASP connection........................................................ 115
Tables
Table 1. Primitives from M3UA to SCTP................................................................................... 20
Table 2. Primitives from SCTP to M3UA................................................................................... 20
Table 3. Status return codes ................................................................................................. 57
Table 4. M3UA MGMT Error codes for Event Type 1 ................................................................ 111

Dialogic®DSI Protocol Stacks M3UA Programmer's Manual Issue 11
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1Introduction
The Dialogic®DSI M3UA module is a software implementation of the IETF
SIGTRAN, SS7 MTP3 User Adaptation Layer (M3UA). This Programmer's
Manual is intended for users choosing to develop their own application
programs that will interface with and use the functionality provided by the
M3UA module.
The module uses the services provided by the Stream Control Transmission
Protocol (SCTP) to exchange signaling messages with M3UA Signaling
Gateway Processes (SGP), M3UA Application Server Processes (ASP) or M3UA
IP Signaling Processes (IPSP). It can be used as part of an ASP or IPSP
system.
The M3UA module is part of the Dialogic®DSI Signaling Protocol product
range and is implemented in a similar message based, event driven manner
to the other protocols in the product range. It is intended to be used in
conjunction with other DSI Signaling Protocols SCTP, ISUP and SCCP either as
part of a pre integrated systems product or integrated with third party
applications and hardware. However, the well-defined message interface
allows the M3UA module to be used with alternative implementations if
required.
This manual provides an overview of the internal operation of the M3UA
module and defines the message based APIs for configuration, management
and applications to use.
1.1 Feature Overview
Key features of the M3UA module include:
Implementation of IETF MTP3 User Adaptation Layer RFC 3332 and RFC
4666 [1]
Message based interface common with other Dialogic®DSI Signaling
Protocols
May be used as part of an ASP or IPSP
May be used as part of a single Local AS or can support Multiple Local AS
Fully automatic or full user control of ASP / AS Activation as required.
Supports Single Exchange Activation
Supports 14, 16 and 24 bit Point Codes
Supports MTP3 User interface to route messages based on DPC
Load-shares across two Signaling Gateways (STPs)
Load-shares across ASPs within a RAS and SGPs within an SG
Load-shares across multiple streams within an SCTP Association
Buffers messages while rerouting
Supports connections to multiple peer ASs
Diagnostic tracing of messages exchanged with SCTP and MTP3 User
Supports SNMP for Links, RAS and Routes
Supports Routing Key Management procedures in ASP mode

Section 1: Introduction
8
1.2 Related Documentation
[1] IETF RFC 4666 MTP3-User Adaptation Layer
[2] IETF RFC 2960 Stream Control Transmission Protocol
[3] Dialogic®DSI SS7 Programmer's Manual for SIGTRAN Host
Software
[4] Dialogic®DSI SCTP Programmer's Manual
[5] Dialogic®DSI Software Environment Programmer's Manual
[6] Enabling Dual-Chassis Fault Tolerance with Dialogic® SIGTRAN
Protocols
1.3 Abbreviations
Abbreviation
Description
AS
Application Server
ASP
Application Server Process
IETF
The Internet Engineering Task Force
IPSP
IP Signaling Point
ISUP
ISDN User Part
ITU
The International Telecommunication Union (Previously CCITT)
M3UA
SS7 MTP3 User Adaptation Layer
MTP2
Message Transfer Part Layer 2
MTP3
Message Transfer Part Layer 3
DPC
Destination Point Code
OPC
Originating Point Code
RC
Routing Context
RK
Routing Key
RKM
Routing Key Management
SCCP
Signaling Connection Control Part
SCTP
Stream Control Transmission Protocol
SG
Signaling Gateway
SGP
Signaling Gateway Process
SNMP
Simple Network Management Protocol
SIGTRAN
The IETF Signaling Transport Group
SS7
Signaling System Number 7

Dialogic®DSI Protocol Stacks M3UA Programmer's Manual Issue 11
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2General Description
2.1 Module Overview
The M3UA module implements the SS7 MTP3-User Adaptation Layer as
defined in the IETF RFC 4666. The module interface is message based. The
module reads messages from a single message input queue and sends
responses and indications to the message input queues of other modules in
the system.
The M3UA module interfaces with SCTP using the User Primitives defined in
the Dialogic© DSI SCTP Programmer's Manual.
2.1.1 ASP and IPSP Operation
When used as part of an ASP or IPSP, M3UA offers a primitive interface to its
Users identical to that of MTP3. This allows M3UA to interface directly to
protocols that interface with MTP3 and for systems that currently use MTP3 to
be easily modified to use M3UA.
The M3UA module allows MTP Tx Indications to be forwarded to signaling end
points, either directly in an IPSP configuration or via STPs in an ASP –SGP
configuration. When M3UA receives a Tx Request from the User it forwards it
based on the DPC in the routing label and configured routes.
When M3UA connects to a peer M3UA it must first establish its SCTP
association, following that it must bring the ASP up and then before sending
traffic it must activate the ASP for the AS. This process may be automated
by M3UA or controlled step by step over the M3UA Management Interface.
M3UA distributes messages received from the network based on the Service
Indicator in the MTP Routing Label.
2.2 Module Configuration
The Configuration interface uses the same message passing environment as
the User and Management API. The full list of configuration messages is
defined in Section 0. Each configuration message will instantiate a new
element and set its configuration parameters as requested, this will include a
logical id for the element. Where one element references another the
referenced element must have been previously configured.
The first configuration message sent to the module must be the module
configuration message M3U_MSG_CONFIG. This tells M3UA where its SCTP
module is, where to send maintenance messages and where to send
management messages.
It is recommended that lower layer protocols are configured first. E.g.
configure SCTP before M3UA before ISUP or SCCP etc.
2.3 System Activation
Once configured the system associations and servers must be brought into
service before traffic can be sent and received. This can be easily achieved by
sending an M3U_MSG_ACTIVATE request message for each association which
has been configured. M3UA will then:
1. Activate the association
2. Wait for the association to come into service (this is indicated to
Layer Management with the M3U_MSG_ASS_STATUS_IND message)

Section 2: General Description
10
3. Send an ASP UP Request to the peer SGP or IPSP
4. Wait for an ASP UP Acknowledgement or retransmit the ASP UP
request (ASP UP is indicated to Layer Management with the
M3U_MSG_ASP_UP_CON or M3U_MSG_ASP_UP_IND message).
5. Optionally perform RKM REG_REQ and handle REG_RSP (ASP only)
6. Send an ASP Activate Request to the peer SGP or IPSP
7. Wait for an ASP Active Acknowledgement or retransmit the ASP
Activate Request (ASP Active is indicated to Layer Management with
the M3U_MSG_ASP_ACT_CON or M3U_MSG_ASP_UP_IND message).
8. The Association is now ready to handle SS7 messages.
If M3U_MSG_ACTIVATE is used to activate the system then should the
association fail M3UA will automatically, without the need for further
requests, reactivate the association.
Some systems require the association to be activated and the ASP to be
brought up without immediately activating the ASP. Should this be the case
then the user can manually activate the association and bring the ASP UP as
follows:
1. Activate association by sending M3U_MSG_ACT_ASSOC
2. Wait for the association to come into service (this is indicated to
Layer Management with the M3U_MSG_ASS_STATUS_IND message)
3. Send an ASP UP Request to the peer by sending
M3U_MSG_ASP_UP_REQ
4. Wait for an ASP UP Acknowledgement or retransmit the ASP UP
request (ASP UP is indicated to Layer Management with the
M3U_MSG_ASP_UP_CON or M3U_MSG_ASP_UP_IND message).
5. If RKM configured for the server a RKM REG_REQ will be initiated if a
RK has previously been configured. Alternatively it will occur as soon
as the RK is configured with M3U_MSG_CNF_RK.
Note: Activation can pause at this point indefinitely. M3UA will be notified
about changes in the availability of any dual partner units and the
distributed service it is part of and may choose to become fully active as
required. This is achieved by taking the following steps:
6. Send an ASP Activate Request by sending M3U_MSG_ASP_ACT_REQ.
7. Wait for an ASP Active Acknowledgement or retransmit the ASP
Activate Request (ASP Active is indicated to Layer Management with
the M3U_MSG_ASP_ACT_CON or M3U_MSG_ASP_UP_IND message).
If associations are activated manually as above it may be desirable to have
M3UA automatically return the association to its previous activation state
following a network failure. Options are available on the ASP UP and ASP
Activate request messages to request this.
Associations can be deactivated by sending the M3U_MSG_DEACTIVATE
message.
2.4 Throughput Monitoring
The M3UA license model allows specific data throughput rates to be used. The
available M3UA licenses and the capability of each are detailed in the table
below:

Dialogic®DSI Protocol Stacks M3UA Programmer's Manual Issue 11
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Description
Throughput
In kilobits
per second
Max
Associations
TDM Link
Equivalents*
SS7SBHSTM3UAU
312kb/s
4
4
SS7SBHSTM3UAT
616kb/s
8
8
SS7SBHSTM3UAS
1,232kb/s
16
16
SS7SBHSTM3UAR
2,464kb/s
32
32
SS7SBHSTM3UAL
4,920kb/s
64
64
SS7SBHSTM3UAK
9,832kb/s
128
128
SS7SBHSTM3UAJ
19,664kb/s
256
256
SS7SBHSTM3UAM
29,496kb/s
384
384
SS7SBHSTM3UAN
39,328kb/s
384
512
SS7SBHSTM3UAP
58,984kb/s
384
768
SS7SBHSTM3UAG
78,648kb/s
384
1024
*This comparison assumes the use of 64kb/s links at a maximum loading of
0.6 Erlang. Individual user deployments may exhibit different characteristics
from this in which case it may be necessary to provision more or less capacity
accordingly
When the module starts it reads its license to determine exactly what data
rate it can use. To support this M3UA provides the following mechanisms to
ensure good visibility and control of the system.
2.4.1 Read current rate and read peak rate.
M3UA supports message type MGT_MSG_R_LIC_STATUS which returns
licensing information about the current state of the system including the
licensed data rate expressed in Kbytes/s. It also supports message type
MGT_MSG_R_THR_STATS which returns the maximum throughput
experienced by the module since the last Restart or Stats Reset. In addition it
reports the total amount of Data transmitted and received. These messages
can be used to see the average and peak throughputs.
The peak and current rates allow users to see what proportion of their
systems throughput capacity is being used.
2.4.2 Notification when license limit exceeded.
If the system exceeds its licensed limit then the system will issue a warning
indication using message type MGT_MSG_LIC_EVENT. This will alert the user
offering an opportunity to throttle the throughput rate. If the throughput rate
continues to exceed the licensed limit then M3UA will issue a subsequent
indication indicating that M3UA is now throttling the rate. Once the rate has
abated below the licensed limit then M3UA will indicate this with a further
MGT_MSG_LIC_EVENT indication.
These indications allow the Customer Application to dynamically throttle the
throughput to stay within the licensed limit.
2.4.3 Notification when 80% of license limit exceeded.
An additional indication is made available when the peak throughput exceeds
80% of the licensed limit. When this happens a MGT_MSG_LIC_EVENT is
generated.

Section 2: General Description
12
This indication can be used by system administrators to help identify systems
coming close to their rated throughput and which may require a license
upgrade. The alarm will persist until the throughput level drops below 40%
of the licensed limit.
2.5 Load Sharing
M3UA data messages sent from a User Part to M3UA for transmission are
formatted starting with the MTP3 Routing Label. This contains a field called
the Signaling Link Selector (SLS) which is used by the SS7 network for load-
sharing of messages through the network. M3UA also uses this for load
sharing of messages. Messages from MTP3 Users are expected to have an
approximately even distribution of SLS values allowing a deterministic spread
of messages through the network.
When transmitting messages to the SS7 network via Signaling Gateways
M3UA will perform the following load sharing steps:
1. Select between two Signaling Gateways using the highest bit in the
SLS.
2. Select between up to sixteen SGPs in the SG using the SLS bits.
3. Select an SCTP Stream in the Association using the lowest bits in the
SLS.
When transmitting messages to an IPSP system which has registered, or is
configured, to operate in load share mode, then the following steps are
taken:
1. Select between up to sixteen ASPs in the RAS using the SLS bits.
2. Select an SCTP Stream in the Association using the lowest bits in the
SLS.
2.6 Dual Resilient Systems
Details of how to configure and use M3UA as part of a Dual Resilient system
may be found in [6] Enabling Dual-Chassis Fault Tolerance with Dialogic®
SIGTRAN Protocols, available from the Dialogic Web Site.

Dialogic®DSI Protocol Stacks M3UA Programmer's Manual Issue 11
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3Configuration Model
This section describes the configurable entities supported by the M3UA
module. This description is intended to assist the user in understanding the
operation of the module. It is not necessary to acquire detailed knowledge of
these entities in order to use the module.
3.1 System Configuration
The M3UA module exists in a message passing environment and has a small
number of parameters controlling how it communicates with other modules.
The first configuration message to be sent to the module must be the module
configuration message (M3U_MSG_CONFIG) which configures these essential
parameters.
M3UA uses a small number of Timers controlling aspects of its behavior.
These take default values as suggested by the M3UA specifications or
otherwise. Should it be necessary these default timer values may be changed
using the timer configuration message (M3U_MSG_CNF_TIMERS). This
changes the M3UA timer values used throughout the module.
3.2 Local Application Server
At least one Local AS must be defined. This is done using the Network
Context configuration message (M3U_MSG_CNF_NC) since a Network Context
maps directly to a Local AS. Four Network Contexts (0 to 3) are supported,
and each may have a different point code format, which enables the LAS to
decode the routing label on Transfer requests and also how to encode the
routing label in Transfer indications sent to the local User Parts.
3.3 Association
M3UA makes use of SCTP Associations for its transport layer connecting it to
peer M3UA Nodes. M3UA requires an association configuration message for
each association used by the system. This message tells M3UA how to
communicate with the SCTP module concerning this Association and whether
the local and remote nodes are Signaling Gateways or Application Hosts.
An SCTP association is similar in concept to a TCP connection. It makes use of
IP and offers a reliable sequenced delivery. Unlike TCP, SCTP is designed to
pass packets as opposed to streaming data. SCTP has been designed by the
IETF for the transport of telecoms signaling.
An Application Host may have associations connecting it to one or more
Signaling Gateways through which it connects to the SS7 network. It may
also have associations connecting it to one or more peer application hosts
which terminate SS7 traffic directly.
At run time each SCTP association must be established and then the M3UA
peers must start communication by sending ASP UP and receiving ASP UP Ack
messages across each association.
Sometimes the peer may use the optional Network Appearance parameter in
certain messages. Should this be the case then M3UA will require a
configuration message for each association on which the Network Appearance
is used (M3U_MSG_MAP_NA).

Section 3: Configuration Model
14
3.4 Server
A Server is a logical entity which controls the routing of SS7 traffic, between
a Signaling Gateway and an SS7 Point Code, or for IPSPs, between two
different SS7 Point Codes.
Once M3UA peers have established communication by sending and receiving
UP requests, Application End Points and Signaling Gateways indicate they are
ready to send and receive SS7 Data traffic by sending and receiving ACTIVE
requests. If a Server is active then M3UA peers can send and receive SS7
traffic.
An Application Host may support one or more Local AS (LAS). A Server
relationship is configured between a LAS and a remote server. A LAS
requires a unique Server relationship for each Signaling Gateway it connects
to. When the Server relationship is active the LAS can send traffic to the
Signaling Gateway; when Inactive it cannot. A LAS connecting to IPSP Hosts
requires a unique Server relationship for each Remote Point Code the peer
hosts support.
A Server relationship may use more than one Association. A separate
configuration message is used to map the Server relationship to each
association it uses and at the same time to specify the Routing Context, if
any, to be used between the peers during Server activation and in SS7 Data
traffic.
Note: Each Server relationship configuration message controls how messages received
from the network are passed to the local User Parts. The message contains an
array of module ids controlling how messages are locally distributed based on the
Service Indicator in the message.
3.5 Routes
A Route maintains the availability status of a remote Point Code in the SS7
network via one or more Signaling Gateways. Each LAS connecting to
Signaling Gateways will require the configuration of Routes for each Remote
Signaling Point Code they wish to communicate with.
The configuration of routes uses two message types; one to declare a new
Remote Point Code for a particular LAS and one to add a Signaling Gateway
to the list of Signaling Gateways used to reach the Point Code.
LAS automatically synchronize their Route State with the Signaling Gateways
and generate PAUSE and RESUME primitive indications to their User Parts.
3.6 Connecting via Signaling Gateways
This example shows the M3UA entities configured when connecting an M3UA
application Host with a single LAS to an SS7 network via a pair of Signaling
Gateways as shown in Figure 1. This shows the M3UA Application Host being
configured, two Signaling Gateway relationships, two SCTP Associations used
to connect to each Signaling Gateway and a number of Destination Point
Codes (DPCs) beyond the Signaling Gateways.
Note: This example only concerns itself with M3UA entities. It is expected that additional
configuration is required for User Parts (ISUP / SCCP), SCTP and other system
elements but this is beyond the scope of this example.

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DPC 1523
DPC 10653
DPC 6379
DPC 1524
Signaling
Gateway
#1
Signaling
Gateway
#2
Association #1
Association #2
Association #3
Association #4
M3UA
Application Host
Figure 1: Connecting via SGs
This example requires the following M3UA configuration:
3.6.1 System Configuration
Configuration of Module IDs using M3U_MSG_CONFIG
Configuration of SS7 Routing Label Format and LAS for Network
Context 0 using M3U_MSG_CNF_NC.
In the event that default timer values require changing then this can be done
at this point.
3.6.2 Association Configuration
Configuration of Association #1 using M3U_MSG_CNF_ASSOC
Configuration of Association #2 using M3U_MSG_CNF_ASSOC
Configuration of Association #3 using M3U_MSG_CNF_ASSOC
Configuration of Association #4 using M3U_MSG_CNF_ASSOC
For all associations set the Host to be an ASP and the peer to be an SGP.
3.6.3 Server Relationship Configuration
Configuration of Signaling Gateway Relationship #1 using
M3U_MSG_CNF_SERVER
Configuration of Signaling Gateway Relationship #2 using
M3U_MSG_CNF_SERVER
For both relationships set the LAS id (0) via the net_ctxt parameter. Set the
Host to be an AS and the peer to be an SG. Set the server to use multiple
users and specify the Module IDs of the User Parts used on the system. Also
set the DAUD option to automatically synchronize routing tables. Set the
default peer traffic mode to load share and the local traffic mode to load
share (unless override or broadcast is required). The Point Code may be set
to zero.
Add Signaling Gateway relationship #1 to Association #1 using
M3U_MSG_ADD_SERV_ASSOC
Add Signaling Gateway relationship #1 to Association #2 to using
M3U_MSG_ADD_SERV_ASSOC
Add Signaling Gateway relationship #2 to Association #3 to using
M3U_MSG_ADD_SERV_ASSOC

Section 3: Configuration Model
16
Add Signaling Gateway relationship #2 to Association #4 to using
M3U_MSG_ADD_SERV_ASSOC
If The Signaling Gateway Expects a Routing Context then this is specified at
this point. If not then set the option to say no routing context is being used.
3.6.4 Route Configuration
Configuration of Route to DPC 6379 using M3U_MSG_CNF_ROUTE
Configuration of Route to DPC 10653 using M3U_MSG_CNF_ROUTE
Configuration of Route to DPC 1523 using M3U_MSG_CNF_ROUTE
Configuration of Route to DPC 1524 using M3U_MSG_CNF_ROUTE
Set the Routes to loadshare between the Signaling Gateways.
Add Route 6379 to Gateway #1 using M3U_MSG_ADD_ROUTE_SERV
Add Route 6379 to Gateway #2 using M3U_MSG_ADD_ROUTE_SERV
Add Route 10653 to Gateway #1 using M3U_MSG_ADD_ROUTE_SERV
Add Route 10653 to Gateway #2 using M3U_MSG_ADD_ROUTE_SERV
Add Route 1523 to Gateway #1 using M3U_MSG_ADD_ROUTE_SERV
Add Route 1523 to Gateway #2 using M3U_MSG_ADD_ROUTE_SERV
Add Route 1524 to Gateway #1 using M3U_MSG_ADD_ROUTE_SERV
Add Route 1524 to Gateway #2 using M3U_MSG_ADD_ROUTE_SERV
Note: If the Destination Point Code of a Route is the Point Code of the Signaling
Gateway itself then it may be necessary to set the option to presume the route is
available as soon as the Server becomes active without receiving a DAVA
message.
3.7 Connecting directly to Peer Applications
This example shows the M3UA entities configured when connecting an M3UA
application Host with a single LAS directly to peer applications without the
use of Signaling Gateways as shown in Figure 2: Connecting to Peer
Applications without Signaling Gateways. This shows the M3UA Application
Host being configured, two Remote Application Server relationships, two
SCTP Associations used to connect to each Remote Application Server (RAS).
Note: Again this example only concerns itself with M3UA entities. It is expected that
additional configuration is required for User Parts (ISUP / SCCP), SCTP and other
system elements but this is beyond the scope of this example.

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Association #1
Association #2
Association #3
Association #4
M3UA
Application Host
Peer
Application
DPC 378
Peer
Application
DPC 12874
Figure 2: Connecting to Peer Applications without Signaling Gateways
This example requires the following M3UA configuration:
Note: There is no Route Configuration required.
3.7.1 System Configuration
Configuration of Module IDs using M3U_MSG_CONFIG
Configuration of SS7 Routing Label Format and LAS for Network
Context 0 using M3U_MSG_CNF_NC
In the event that default timer values require changing then this can be done
at this point.
3.7.2 Association Configuration
Configuration of Association #1 using M3U_MSG_CNF_ASSOC
Configuration of Association #2 using M3U_MSG_CNF_ASSOC
Configuration of Association #3 using M3U_MSG_CNF_ASSOC
Configuration of Association #4 using M3U_MSG_CNF_ASSOC
For all associations set both the Host and Peer to be ASPs.
3.7.3 Server Relationship Configuration
Configuration of RAS relationship #1 using M3U_MSG_CNF_SERVER
Configuration of RAS relationship #2 using M3U_MSG_CNF_SERVER
For both relationships set the LAS id (0) via the net_ctxt parameter. Set the
Host and Peer to be an AS. Set the server to use multiple users and specify
the Module IDs of the User Parts used on the system. The DAUD option
should not be set. Set the default peer traffic mode to load share and the
local traffic mode to load share (unless override or broadcast is required). The
Point Codes must be set to the point code of the peer server.
Add RAS relationship #1 to Association #1 using
M3U_MSG_ADD_SERV_ASSOC
Add RAS relationship #1 to Association #2 using
M3U_MSG_ADD_SERV_ASSOC

Section 3: Configuration Model
18
Add RAS relationship #2 to Association #3 using
M3U_MSG_ADD_SERV_ASSOC
Add RAS relationship #2 to Association #4 using
M3U_MSG_ADD_SERV_ASSOC
If the Application Server expects a Routing Context then this is specified at
this point. If not then set the option to say no routing context is being used.

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4Interface to system services
4.1 System Functions
In addition to the primitive interface and the management interface to the
M3UA module (which is described in Section 6: Message Reference), the
module requires a few basic system services to be supplied by the underlying
operating system. This functionality is usually supplied by the appropriate
Dialogic©DSI Development package.
The following functions are required for inter-task communication:
Function
Description
GCT_send
Sends a message to another task.
GCT_receive
Accepts next message from input event queue,
blocking the task if no message is ready.
GCT_grab
As for GCT_receive but not blocking if no message is
ready.
The following functions are required for allocation of inter-task messages:
Function
Description
getm
Allocates a message.
relm
Releases a message.
4.2 Timer Operation
In order to provide internal implementation of the M3UA protocol timers the
module needs to receive a periodic timer tick message. This is provided by
the tick and tim processes which send a timer tick message to M3UA every
100ms.

Section 5: External Message Definitions: SCTP
20
5External Message Definitions: SCTP
The Dialogic® DSI M3UA module is intended to interface to the Dialogic®
DSI SCTP module. However it can interface with any other implementation of
SCTP which satisfies the SCTP / User interface defined in the SCTP
Programmer’s Manual. For example this may include operating system
specific SCTP implementations interfaced using the Dialogic® DSI SCTPN
interface module included in the Dialogic® DSI development packages for
Linux and Solaris.
The following primitives are used:
Table 1. Primitives from M3UA to SCTP
SCTP Activate association
(0x728a)
Servers wait for incoming assoc / Client attempt
association
SCTP Shutdown association
(0x728b)
Gracefully close down association
SCTP Abort association
(0x728c)
Initiate the abort of an association
SCTP Data transfer request
(0xc280)
Transmit a data packet
Table 2. Primitives from SCTP to M3UA
SCTP Status change
(0x028d)
Association status change
SCTP Data transfer indication
(0x8281)
Received data packet
SCTP Congestion status
(0x028f)
Change in the congestion status of the association
SCTP Network status
(0x028e)
Status of a network address within an association
has changed