Engenharia de Comunicações - 2006/07
Telecommunications Systems 2
Signalling Systems
Sistemas de Telecomunicações II - 3.1
Engenharia de Comunicações - 2006/07
SIGNALLING SYSTEMS
ITU-T Q.110
Analogue and Digital
Signalling System R1 (USA) and R2 (EUR)
• Line Signalling
Signalling System No. 4 (1954) and No. 5 (1964)
• In-band signalling systems
• Circuits connected on a 4-wire basis
• Circuits routed partly or wholly via PCM transmission systems
Signalling System No. 6 (1968)
• Analogue voice-frequency /PCM voice-frequency channels
• Circuits connected on a 4-wire basis
• Transmission of signalling information over digital systems / Satellite
Sistemas de Telecomunicações II - 3.2
Engenharia de Comunicações - 2006/07
SIGNALLING SYSTEMS
Signalling System No. 7 (1980)
Developed for the use in integrated digital networks
Optimized for 64 kbit/s PCM transmission channels
Can be used on analogue transmission channels
Digital Subscriber Signalling System No. 1
Integrated Services Digital Network (ISDN)
Digital Subscriber Signalling System No. 2
Broadband Integrated Services Digital Network (B-ISDN/ATM)
Sistemas de Telecomunicações II - 3.3
Engenharia de Comunicações - 2006/07
Definitions
ITU-T Q.9
Communication: - Information transfer according to agreed conventions.
In the context of the present vocabulary, the ordinary dictionary
meaning of the term is appropriate and sufficient.
The French term "communication" and the Spanish term "comunicación" have the
current meaning given in this definition, but they also acquire a more specific
meaning in telecommunication.
Telecommunication: - Any process that enables a correspondent to pass
to one or more given correspondents (telegraphy or telephony), or
possible correspondents (broadcasting), information of any nature
delivered in any usable form (written or printed matter, fixed or
moving pictures, words, music, visible or audible signals, signals
controlling the functioning of mechanisms, etc.) by means of any
electromagnetic system (electrical transmission by wire, radio
transmission, optical transmission, etc., or a combination of such
systems).
Sistemas de Telecomunicações II - 3.4
Engenharia de Comunicações - 2006/07
Definitions
ITU-T Q.9
Connection: - An association of transmission channels or circuits,
switching and other functional units set up to provide a means for a
transfer of information between two or more points in a
telecommunication network.
Call: - The action performed by a calling party in order to obtain
communication with the wanted terminal equipment and by extension,
the operations controlled by the action performed; The use, or the
possible use, of a complete connection set up between a calling party
and the called party or service.
Exchange: - An aggregate of traffic carrying devices, switching stages,
controlling and signalling means at a network node that enables
subscriber lines and/or other telecommunication circuits to be
interconnected as required by individual users.
Handover: - The action of switching a call in progress.
Sistemas de Telecomunicações II - 3.5
Engenharia de Comunicações - 2006/07
Definitions
ITU-T Q.9
Service, telecommunication service: - That which is offered by an
Administration or Recognized Private Operating Agency (RPOA) to
its customers in order to satisfy a specific telecommunication
requirement.
Bearer service: - A type of telecommunication service that provides the
capability for the transmission of signals between user network
interfaces (the ISDN connection type used to support a bearer service
may be identical to that used to support other types of
telecommunication service).
Teleservice:- A type of telecommunication service that provides the
complete capability, including terminal equipment functions, for
communication between users according to protocols established by
agreement between Administrations and/or RPOAs.
Basic service:- The fundamental type of service, or the most commonly
provided service in a telecommunications network. It forms the basis
upon which supplementary services may be added.
Supplementary service; - Any service provided by a network in addition
to its basic service or services.
Sistemas de Telecomunicações II - 3.6
Engenharia de Comunicações - 2006/07
Definitions
Signalling
The exchange of information (other than by speech) specifically
concerned with the establishment, release and other control of calls,
and network management, in automatic telecommunications
operation.
A qualification implying an action as defined above, e.g.:
signalling channel
signalling procedure
signalling equipment
signalling relation
signalling information
signalling route
signalling link
signalling system
signalling message
signalling time slot
Sistemas de Telecomunicações II - 3.7
Engenharia de Comunicações - 2006/07
Definitions
Switching
The establishing, on demand, of an individual connection from a
desired inlet to a desired outlet within a set of inlets and outlets for
as long as is required for the transfer of information.
A qualification implying the action as defined above, e.g.:
switching centre
switching network
switching delay
switching node
switching device
switching point
switching equipment
switching system
switching exchange
switching unit
switching matrix
Sistemas de Telecomunicações II - 3.8
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(Local) Exchange
Sistemas de Telecomunicações II - 3.9
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Generic Addressing and Transport Protocol
Protocol for exchanging
Application Protocol Data Units (APDUs)
between service provision points
that may be located within the same network,
between networks, or
between a terminal and a network.
May be used in conjunction with:
– Digital Subscriber Signalling System No. 1 (DSS1);
– Digital Subscriber Signalling System No. 2 (DSS2);
– Signalling System No. 7 (SS No. 7).
Sistemas de Telecomunicações II - 3.10
Engenharia de Comunicações - 2006/07
Definitions
APDU Application Protocol Data Unit
APM Application Protocol Mechanism
AS-ASE Application Service
Application Service Element
AS-Control Application Service
Control
DSS1 Digital Subscriber Signalling
System No. 1
DSS2 Digital Subscriber Signalling
System No. 2
GAT Generic Addressing and
Transport
GAT-Control Generic Addressing and
Transport Control
GAT-PDU Generic Addressing and
Transport Protocol Data Unit
IN Intelligent Network
ISUP ISDN User Part
N-ISDN Narrow-band Integrated
Services Digital Network
PDU Protocol Data Unit
PINX Private Integrated Services
Network Exchange
PSPDN Packet Switched Public Data
Network
ROSE Remote Operations Service
Element
SCP Service Control Point
SS No. 7 Signalling System No. 7
SSP Service Signalling Point
TCAP Transaction Capabilities
Application Part
Sistemas de Telecomunicações II - 3.11
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Generic Addressing and Transport Protocol
Transport mechanisms
Bearer-related service
Connection-oriented bearer-independent service
Sistemas de Telecomunicações II - 3.12
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Generic Addressing and Transport Protocol
Services provided by GAT-control
• Bearer-related service
– GAT-Setup: request for the transfer of data in the bearer establishment phase.
– GAT-Release: request for the transfer of data in the bearer release phase.
– GAT-Reject: rejection of the ability to use a transport mechanism.
– GAT-Data: request for the transfer of data in the active phase of a bearer.
• Connection-oriented bearer-independent service
– GAT-Setup: request for the establishment of a bearer-independent signalling
association (with data transfer if required).
– GAT-Release: request for the release of a bearer-independent signalling association
(with data transfer if required).
– GAT-Reject: rejection of the ability to use a transport mechanism
– GAT-Data: request for the transfer of data in the active phase of a bearer-independent
signalling association.
Sistemas de Telecomunicações II - 3.13
Engenharia de Comunicações - 2006/07
Generic Addressing and Transport Protocol
Services provided by the transport mechanisms
• Bearer-related service
-
Transport-Setup: request for the transfer of data in the bearer establishment phase.
Transport-Release: request for the transfer of data in the bearer release phase.
Transport-Reject: rejection of the ability to use a transport mechanism.
Transport-Data: request for the transfer of data in the active phase of a bearer.
• Connection-oriented bearer-independent service
– Transport-Setup: request for the establishment of a bearer-independent signalling
association (with data transfer if required).
– Transport-Release: request for the release of a bearer-independent signalling
association (with data transfer if required).
– Transport-Reject: rejection of the ability to use a transport mechanism.
– Transport-Data: request for the transfer of data in the active phase of a bearerindependent signalling association.
Sistemas de Telecomunicações II - 3.14
Engenharia de Comunicações - 2006/07
Addressing Mechanisms
Transport mechanism addresses
These addresses are provided per transport mechanism (included in the first transport
mechanism establishment message).
Transport mechanism addresses may influence routing of the transport mechanism.
– Origin of the transport mechanism;
– Endpoint of the transport mechanism;
For the bearer-related transport mechanism, this is identical to the
address of the called party.
– Selected service provider;
Not for the bearer-independent connectionless transport mechanism.
– Source entity;
– Destination entity;
– Service indicator.
GAT addresses
Sistemas de Telecomunicações II - 3.15
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Generic Addressing and Transport Protocol
Sistemas de Telecomunicações II - 3.16
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Remote Operations Model
Sistemas de Telecomunicações II - 3.17
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Protocol model
Sistemas de Telecomunicações II - 3.18
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Components of the ROPM state
Sistemas de Telecomunicações II - 3.19
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Remote Operations Service Element
Model of an application context
involving remote operations
Association Control
Service Element (ACSE)
Reliable Transfer Service
Element (RTSE)
Sistemas de Telecomunicações II - 3.20
Engenharia de Comunicações - 2006/07
Basic ROSE elements
• The basic ROSE protocol consists of the
following elements of procedure:
– association-establishment;
– association-release;
– association-abort;
– invocation;
– return-result;
– return-error;
– user-reject;
– provider-reject.
Sistemas de Telecomunicações II - 3.21
Engenharia de Comunicações - 2006/07
Remote Operations Model
•
Operations invoked by one AE (the invoker) are performed by the other AE
(the performer). Operations may be classified according to whether the
performer of an operation is expected to report its outcome:
- in case of success or failure (a result reply is returned if the operation is successful, an
error reply is returned if the operation is unsuccessful);
- in case of failure only (no reply is returned if the operation is successful, an error
reply is returned if the operation is unsuccessful);
- in case of success only (a result reply is returned if the operation is successful, no
reply is returned if the operation is unsuccessful);
- or not at all (neither a result nor an error reply is returned, whether the operation was
successful or not).
Sistemas de Telecomunicações II - 3.22
Engenharia de Comunicações - 2006/07
Application-associations
•
Application-associations are classified by which application-entity is
allowed to invoke operations:
– Association Class 1: Only the association-initiating application entity can
invoke operations.
– Association Class 2: Only the association-responding application entity
can invoke operations.
– Association Class 3: Both the association-initiating and the associationresponding application entities can invoke operations.
Sistemas de Telecomunicações II - 3.23
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Generic Functional Protocol
Conceptual model
•Bearer-related transport;
•Connectionless bearerindependent transport;
•Connection-oriented bearerindependent transport.
Sistemas de Telecomunicações II - 3.24
Engenharia de Comunicações - 2006/07
Services provided by GFT-control
•
Bearer-related service
– GFT-Setup: request for the transfer of data in the bearer establishment phase.
– GFT-Release: request for the transfer of data in the bearer release phase.
– GFT-Reject: rejection of the ability to use a transport mechanism.
– GFT-Data: request for the transfer of data in active phase of a bearer.
•
Connectionless bearer-independent service
– GFT-Unit Data: request for the transfer of data.
•
Connection-oriented bearer-independent service
– GFT-Setup: request for the establishment of a bearer-independent signalling
association (with data transfer if required).
– GFT-Release: request for the release of a bearer-independent signalling
association (with data transfer if required).
– GFT-Reject: rejection of the ability to use a transport mechanism.
– GFT-Data: request for the transfer of data in active phase of a bearerindependent signalling association.
Sistemas de Telecomunicações II - 3.25
Engenharia de Comunicações - 2006/07
Services provided by bearer-related
transport
• Any of the bearer-related procedures specified in Rec.
Q.2931 and Q.2971 can be used for bearer-related
protocol control.
• In addition, these services provide one additional service:
– BR-Data: this service is an unconfirmed service.
Services provided by connectionless
bearer-independent transport
• Connectionless bearer-independent transport provides the
following services to GFT-Control via the coordination
function:
– CL-BI-Unit Data: This service is an unconfirmed service.
Sistemas de Telecomunicações II - 3.26
Engenharia de Comunicações - 2006/07
Services provided by connectionoriented bearer-independent transport
• Connection-oriented bearer-independent transport
provides the following services to GFT-Control via the
coordination function:
–
–
–
–
CO-BI-Setup: this service is a confirmed service;
CO-BI-Release: this service is a confirmed service;
CO-BI-Reject: this service is an unconfirmed service;
CO-BI-Data: this service is an unconfirmed service.
• In addition, connection-oriented bearer-independent
transport also supports a notification data transfer service
as follows:
– CO-BI-Notification: this service is an unconfirmed service.
Sistemas de Telecomunicações II - 3.27
Engenharia de Comunicações - 2006/07
Generic Functional Protocol
Local information exchange
Sistemas de Telecomunicações II - 3.28
Engenharia de Comunicações - 2006/07
Generic Functional Protocol
Multiple subscriber number and
subaddressing supplementary services
Sistemas de Telecomunicações II - 3.29
Engenharia de Comunicações - 2006/07
Structures for the international public
telecommunication number
Number for geographic areas
CC Country Code for geographic areas
n Number of digits in the country code
NDC National Destination Code (optional)
SN Subscriber Number
Sistemas de Telecomunicações II - 3.30
Engenharia de Comunicações - 2006/07
Structures for the international public
telecommunication number
Number for global services
CC Country Code for geographic areas
GSN Global Subscriber Number
Sistemas de Telecomunicações II - 3.31
Engenharia de Comunicações - 2006/07
Structures for the international public
telecommunication number
Number for networks
CC Country Code for geographic areas
IC Identification Code
x Number of digits in Identification Code
SN Subscriber Number
Sistemas de Telecomunicações II - 3.32
Engenharia de Comunicações - 2006/07
Number portability
Conceptual framework for incoming calls
Sistemas de Telecomunicações II - 3.33
Engenharia de Comunicações - 2006/07
Number portability mechanisms
•
Call rerouted from donor network by use of onward routing principles
•
Call rerouted by dropback principles from donor network
Sistemas de Telecomunicações II - 3.34
Engenharia de Comunicações - 2006/07
Number portability mechanisms
•
Call rerouting initiated by "Query on Release (QoR) " principles from
donor network
•
Routing initiated by "All call query" principles
Sistemas de Telecomunicações II - 3.35
Engenharia de Comunicações - 2006/07
Digital subscriber Signalling System No. 1
Interface to call control
Sistemas de Telecomunicações II - 3.36
Engenharia de Comunicações - 2006/07
Digital subscriber Signalling System No. 1
LAPD - Link Access Procedure on the D-channel
Sistemas de Telecomunicações II - 3.37
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 1
Primitive sequences
Sistemas de Telecomunicações II - 3.38
Engenharia de Comunicações - 2006/07
Digital subscriber Signalling System No. 1
User-network interface
management
•
•
•
•
•
Physical layer profile
– Basic rate physical layer
– Primary rate physical layer
Data link layer profile
Network layer profile
– Use of the extended facility
information element
– Call independent management
procedures
– Call associated management
procedures
Convergence function
Application layer
–
–
–
–
–
Association control
Remote operations
Common management information service
System management application service
element (SMASE)
Syntax and encoding
Sistemas de Telecomunicações II - 3.39
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 2
B-ISDN signalling reference configuration
Sistemas de Telecomunicações II - 3.40
Engenharia de Comunicações - 2006/07
Signalling protocol stacks
At the UNI
Sistemas de Telecomunicações II - 3.41
Engenharia de Comunicações - 2006/07
Signalling protocol stacks
At the NNI
the ATM network is used
Sistemas de Telecomunicações II - 3.42
Engenharia de Comunicações - 2006/07
Signalling protocol stacks
At the NNI
the existing SS No. 7 network interface is used
Sistemas de Telecomunicações II - 3.43
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 2
Meta-signalling protocol
The Meta-signalling protocol has procedures for the:
– assignment of a point-to-point signalling virtual channel and an
associated broadcast signalling virtual channel;
– assignment of a point-to-point signalling virtual channel;
– checking of the status of signalling virtual channels;
– removal of signalling virtual channels.
Using these procedures, Plane Management can:
– resolve the possible contention for particular signalling virtual channels;
– allocate cell rate to signalling virtual channels;
– allocate a broadcast signalling virtual channel identity;
– associate a signalling endpoint with a particular point-to-point signalling
and broadcast signalling virtual channel pair.
Sistemas de Telecomunicações II - 3.44
Engenharia de Comunicações - 2006/07
Meta-signalling protocol architecture model
Sistemas de Telecomunicações II - 3.45
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 2
Signalling relations under control of Meta-signalling
PSVCI - Point-to-point Signalling Virtual Channel Identifier
GBSVCI - General Broadcast Signalling Virtual Channel Identifier
SBSVCI - Selective Broadcast Signalling Virtual Channel Identifier
UMSPE - User Meta-signalling Protocol Entity
NMSPE - Network Meta-signalling Protocol Entity
Sistemas de Telecomunicações II - 3.46
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 2
Signalling higher layer functions
UNI
Call/connection control functions:
– call establishment and release;
– bearer establishment and release, for point-to-point VCCs;
– compatibility checking;
– support of N-ISDN services;
– signalling interworking between N-ISDN and B-ISDN.
NNI
Call/bearer connection control functions:
– call establishment and release;
– bearer connection establishment and release, for point-to-point VCCs;
– transfer of access transport information;
– interworking with N-ISDN services.
Sistemas de Telecomunicações II - 3.47
Engenharia de Comunicações - 2006/07
ATM Adaptation Layer (AAL) functions
Sistemas de Telecomunicações II - 3.48
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Services of the SAAL at the UNI
Unacknowledged Transfer of Data: The SAAL service provides for the
unacknowledged transfer of SAAL service data units on point-to-point and
point-to-multipoint ATM connections. The SAAL supports the transfer of octet
aligned SDUs up to a maximum of 4096 octets (i.e. maximum information size
k in UD-PDU). The SAAL unacknowledged data transfer service does not
relieve the user from loss or insertion of data which may occur.
Assured Transfer of Data: The SAAL service provides for the assured transfer of
SAAL service data units on point-to-point ATM connections. The SAAL
supports the transfer of octet aligned SDUs up to a maximum of 4096 octets
(i.e. maximum information size k in SD PDU). The SAAL service relieves the
user from loss, insertion, corruption, and misordering of data which may
occur. In some cases due to unrecoverable errors in the ATM adaptation
layer, duplication or loss of SDUs may occur.
Transparency of Transferred Information: The SAAL service provides for the
transparent transfer of SAAL service data units. It does not restrict the
content, format or coding of information, nor does it ever need to interpret its
structure or meaning.
Establishment and Release of SAAL Connections for Assured Transfer of Data:
The SAAL service provides a means to establish and release SAAL connections
which operate in the assured mode. In some cases, the SAAL service provider
may release the SAAL connection. Depending on the conditions, release of an
SAAL connection may result in loss of SAAL user-data.
Sistemas de Telecomunicações II - 3.49
Engenharia de Comunicações - 2006/07
SAAL primitives used at the UNI
Sistemas de Telecomunicações II - 3.50
Engenharia de Comunicações - 2006/07
SAAL primitives used at the UNI
The AAL-ESTABLISH request/indication/confirm: This is used for
establishing assured information transfer between AAL entities at the
UNI. This is only required in conjunction with point-to-point
signalling virtual connections.
The AAL-RELEASE request/indication/confirm: This is used for
terminating assured information transfer between AAL entities at the
UNI. This is only required in conjunction with point-to-point
signalling virtual connections.
The AAL-DATA request/indication: This is used in conjunction with
assured SDU data transfer at the UNI. It is assumed that assured
information transfer was initiated with the ESTABLISH primitive. This
is only required in conjunction with point-to-point signalling virtual
connections.
The AAL-UNITDATA request/indication: This is used in conjunction
with unacknowledged SDU data transfer at the UNI. This is required
in conjunction with broadcast and point-to-point signalling virtual
connections.
Sistemas de Telecomunicações II - 3.51
Engenharia de Comunicações - 2006/07
State transition diagram
Point-to-point
states:
1 - AAL connection
released state;
2 - awaiting establish
state;
3 - awaiting release
state;
4 - AAL connection
established state.
Sistemas de Telecomunicações II - 3.52
Engenharia de Comunicações - 2006/07
AAL structure for signalling applications
SAAL - Signalling AAL
SAP - Service Access Point
SAR -Segmentation And
Reassembly
SSCF - Service Specific
Coordination Function
SSCOP - Service Specific
Connection Oriented
Protocol
SSCS - Service Specific
Convergence Sublayer
CPCS - Common Part
Convergence Sublayer
Sistemas de Telecomunicações II - 3.53
Engenharia de Comunicações - 2006/07
Service Specific Connection Oriented Protocol
The SSCOP is a peer-to-peer
protocol which provides the
following functions:
– transfer of user data with sequence
integrity;
– error correction by selective
retransmission;
– flow control;
– connection control;
– error reporting to layer management;
– connection maintenance in the
prolonged absence of data transfer;
– local data retrieval by the user;
– error detection of protocol control
information; and
– status reporting.
Sistemas de Telecomunicações II - 3.54
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 2
• User-Network Interface (UNI) layer 3 specification
- for basic call/connection control
- for point-to-multipoint call/connection control
• Q.2931-based separated call control protocol
• Bearer control protocol
• Generic functional protocol
• Generic identifier transport
- Extensions (for support of bearer independent call
control)
Sistemas de Telecomunicações II - 3.55
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 2
Sistemas de Telecomunicações II - 3.56
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 2
Call association information element
Sistemas de Telecomunicações II - 3.57
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 2
Bearer identifier information element
Sistemas de Telecomunicações II - 3.58
Engenharia de Comunicações - 2006/07
Message format and information elements
AAL parameters information element
Sistemas de Telecomunicações II - 3.59
Engenharia de Comunicações - 2006/07
AAL parameters information elements
Sistemas de Telecomunicações II - 3.60
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Frame format of B-ISUP and MTP-3 over SAAL
Sistemas de Telecomunicações II - 3.61
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Digital Subscriber Signalling System No. 2
CO-BI transport mechanism
Sistemas de Telecomunicações II - 3.62
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 2
Addressing of APDUs
Sistemas de Telecomunicações II - 3.63
Engenharia de Comunicações - 2006/07
Successful ATM connection establishment
with traffic parameter negotiation
Sistemas de Telecomunicações II - 3.64
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Digital Subscriber Signalling System No. 2
Additional traffic parameters
- Additional signalling capabilities to support traffic parameters for the
tagging option and the sustainable cell rate parameter set
- Support of ATM transfer capability in the broadband bearer capability
information element
- Signalling capabilities to support traffic parameters for the available bit
rate (ABR) ATM transfer capability
- Signalling capabilities to support traffic parameters for the ATM Block
Transfer (ABT) ATM transfer capability
- Additional traffic parameters for cell delay variation tolerance
indication
- Additional signalling procedures for the support of the Statistical Bit
Rate (SBR) ATM transfer capabilities
Sistemas de Telecomunicações II - 3.65
Engenharia de Comunicações - 2006/07
Negotiation during call/connection establishment phase
• Connection characteristics
• Connection modification
- Peak cell rate modification by the connection owner
- Modification procedures for sustainable cell rate
parameters
- ATM traffic descriptor modification with negotiation
by the connection owner
• Support of Quality of Service classes
- Signalling of individual Quality of Service parameters
Sistemas de Telecomunicações II - 3.66
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 2
• Signalling specification for Frame Relay service
• Switched virtual path capability
- Application of DSS2 service-related information
elements by equipment supporting B-ISDN services
• Call priority
• B-ISDN and broadband private integrated
services network (B-PISN)
- Call control protocol
- Pre-negotiation
Sistemas de Telecomunicações II - 3.67
Engenharia de Comunicações - 2006/07
Frame Relaying connection between
a B-ISDN user and a PDN user
Sistemas de Telecomunicações II - 3.68
Engenharia de Comunicações - 2006/07
B-ISDN application protocols for the network signalling
• Network Node Interface specification for point-to-multipoint
call/connection control
• Look-ahead without state change for the Network Node Interface
• Call priority
• Network generated session identifier
• Extensions to the B-ISDN user part - Application generated identifiers
• Signalling System No. 7 B-ISDN user part (B-ISUP)
–
Supplementary services
• Closed User Group (CUG)
–
–
–
–
–
–
Extension of Q.751.1 for SAAL signalling links
Functional description of the B-ISUP
General functions of messages and signals
Formats and codes
Basic call procedures
Application transport mechanism (APM)
Sistemas de Telecomunicações II - 3.69
Engenharia de Comunicações - 2006/07
Point-to-multipoint call/connection control
Supported capabilities:
–Establishment of a call/connection
containing one point-to-multipoint
network connection requested by the
root party of the network connection.
–Addition of one new party,
requested by the root party of the
network connection.
–Drop of a leaf party from an
existing call/connection, requested by
the root party.
–Drop of a leaf party from an
existing call/connection, requested by
the party itself.
–Release of the call/connection,
requested by the root party.
Actions to be taken at six
exchange types:
– originating exchange;
– intermediate national
exchange;
– outgoing international
exchange;
– intermediate international
exchange;
– incoming international
exchange;
– destination exchange.
Sistemas de Telecomunicações II - 3.70
Engenharia de Comunicações - 2006/07
Example for the user plane configuration of a point-to-multipoint call
Root: The source of the point-to-multipoint connection.
Leaf: One of the destinations of the point-to-multipoint connection.
Sistemas de Telecomunicações II - 3.71
Engenharia de Comunicações - 2006/07
Management of VPCI value and
bandwidth of each VPC pool
Before a route between two exchanges can be put
into service, the following is necessary:
- the VPCIs to be used must be assigned unambiguously
and identically at both exchanges;
-VPC pools must be defined on a physical interface basis
identically at both exchanges;
-each VPC pool consists of a continuous range of
VPCIs;
- a bandwidth pool must be allocated to each VPC pool
identically at both exchanges;
- for every VPC pool it must be defined which exchange.
Sistemas de Telecomunicações II - 3.72
Engenharia de Comunicações - 2006/07
Management of VPCIs and bandwidth
resources between a pair of exchanges
Sistemas de Telecomunicações II - 3.73
Engenharia de Comunicações - 2006/07
Possible relationships between VPCIs,
VPIs, bandwidth pools and interfaces
Sistemas de Telecomunicações II - 3.74
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 2
Multiple interfaces controlled by SVC
Sistemas de Telecomunicações II - 3.75
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 2
GFP - Fully terminated Interworking with N-ISDN
Sistemas de Telecomunicações II - 3.76
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 2
GFP - Generic interworking
Sistemas de Telecomunicações II - 3.77
Engenharia de Comunicações - 2006/07
Digital Subscriber Signalling System No. 2
Supplementary services
Stage 3 description for number identification
- Basic Call
- Support of ATM end system addressing format by Number
identification
Stage 3 description for community of interest
- Closed User Group (CUG)
Stage 3 description for additional information
transfer
- Basic call
- User-to-user signalling (UUS)
Sistemas de Telecomunicações II - 3.78
Engenharia de Comunicações - 2006/07
N-ISDN Services not supported by B-ISDN
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Call Forwarding Busy
Call Forwarding No Reply
Call Forwarding Unconditional
Call Deflection
Call Waiting
Call Hold
Conference Add-on Call
Three-Party Service
Terminal Portability
Multi-level Precedence and Preemption
User-to-User Signalling 1 (explicit)
User-to-User Signalling 2
User-to-User Signalling 3
Explicit Call Transfer (ECT)
Malicious Call Identification (MCID)
Completion of calls to busy subscribers (CCBS)
Mapping tables
Completion of calls – no reply (CCNR)
Global Virtual Network Service (GVNS)
Reverse charging
Sistemas de Telecomunicações II - 3.79
Engenharia de Comunicações - 2006/07
Interworking between SS7 B-ISUP and DSS2
•
•
•
•
Interworking for successful call set-up procedures
Interworking for call release procedures
Interworking for unsuccessful call set-up procedures
Interworking for Supplementary services
–
–
–
–
–
–
–
Direct-Dialling-In
Multiple Subscriber Number
CLIP/CLIR
COLP/COLR
Interworking specification for the Sub-address
UUS 1 supplementary services
Closed User Group
Sistemas de Telecomunicações II - 3.80
Engenharia de Comunicações - 2006/07
Signalling System No. 7
•
Message Transfer Part (MTP)
– the ISDN User Part (ISUP)
– the Telephone User Part (TUP)
– the Signalling Connection Control Part (SCCP)
– the Data User Part (DUP)
•
•
•
Telephone User Part (TUP)
ISDN User Part (ISUP)
Signalling Connection Control Part (SCCP)
– the ISDN User Part (ISUP)
– Transaction Capabilities (TC)
– Operations Maintenance and Administration Part (OMAP)
•
•
•
Transaction Capabilities (TC)
Application Entity (AE)
Application Service Elements (ASEs)
Sistemas de Telecomunicações II - 3.81
Engenharia de Comunicações - 2006/07
Signalling System No. 7 Architecture
Sistemas de Telecomunicações II - 3.82
Engenharia de Comunicações - 2006/07
Functional levels
Sistemas de Telecomunicações II - 3.83
Engenharia de Comunicações - 2006/07
Functional interface
Message Transfer Part and the User Parts
Sistemas de Telecomunicações II - 3.84
Engenharia de Comunicações - 2006/07
Signalling message structure
Sistemas de Telecomunicações II - 3.85
Engenharia de Comunicações - 2006/07
Signalling message structure
BIB - Backward indicator bit
BSN - Backward sequence number
CK - Check bits
F - Flag
FIB - Forward indicator bit
FSN - Forward sequence number
LI - Length indicator
SF - Status field
SIF - Signalling information field
SIO - Service information octet
Sistemas de Telecomunicações II - 3.86
Engenharia de Comunicações - 2006/07
Message Transfer Part
Signalling link control
Sistemas de Telecomunicações II - 3.87
Engenharia de Comunicações - 2006/07
Message Transfer Part
Signalling Network Level
•
•
Message handling
Signalling network management
Signalling Data Link Level
•
•
•
Transmitted blocks are delivered with no errors, losses or
duplication.
The blocks are delivered in the proper order.
The receiver is capable of exercising flow control over the
transmitted data.
- Fill In Signal Unit (FISU)
- Link Status Signal Unit (LSSU)
- Message Signal Unit (MSU)
Sistemas de Telecomunicações II - 3.88
Engenharia de Comunicações - 2006/07
Signalling network functions
Signalling network
management
Status of signalling links
Signalling link failure
Signalling link restoration
Signalling link deactivation
Signalling link activation
Signalling link blocking
Signalling link unblocking
Signalling link inhibiting
Signalling link uninhibiting
Procedures used in connection
with link status changes
Signalling link failed
Signalling link restored
Signalling link deactivated
Signalling link activated
Signalling link blocked
Signalling link unblocked
Signalling link inhibited
Signalling link uninhibited
Status of signalling routes
Signalling route unavailability
Signalling route availability
Signalling route restricted1
Procedures used in connection
with route status changes
Signalling route unavailable
Signalling route available
Signalling route restricted1
Status of signalling points
Signalling point unavailability
Signalling point availability
Procedures used in connection
with point status changes
Signalling point unavailable
Signalling point available
Signalling network congestion
Congestion status of signalling links
Procedures used in connection with link
congestion status changes
Congestion status of signalling route sets
Procedures used in connection with route set
congestion status changes
Sistemas de Telecomunicações II - 3.89
Engenharia de Comunicações - 2006/07
Message Transfer Part
Signalling traffic management (STM)
Sistemas de Telecomunicações II - 3.90
Engenharia de Comunicações - 2006/07
Telephone User Part
General function of telephone signalling messages and signals
• Telephone signalling messages
• Service information
– Service indicator
– Network indicator
• Signalling information
–
–
–
–
–
–
–
–
Label components
Message format identifiers
Forward set-up telephone signals
Backward set-up telephone signals
Call supervision signals
Circuit supervision signals
Circuit group supervision messages
Automatic congestion control signals
Sistemas de Telecomunicações II - 3.91
Engenharia de Comunicações - 2006/07
Telephone signalling messages
•
Forward address message group
•
Forward set-up message group
•
Backward set-up request message group
•
Successful backward set-up information message group
•
Unsuccessful backward set-up information message group
•
•
•
•
Call supervision message group
Circuit supervision message group
Circuit group supervision message group
Circuit network management message group
–
–
–
–
Initial address message
Initial address message with additional information
Subsequent address message
Subsequent address message with one signal
–
–
General forward set-up information message
Continuity check message
–
General request message
–
–
Address-complete message
Charging message
–
–
Simple unsuccessful backward set-up information message
Extended unsuccessful backward set-up information message
–
Automatic congestion control information message
Sistemas de Telecomunicações II - 3.92
Engenharia de Comunicações - 2006/07
ISDN User Part
Procedures and functions used within the network
in order to provide the users with circuitswitched services for voice and non-voice calls
•
•
•
•
•
•
Closed user group
User access to calling party address identification
User access to called party address identification
Redirection of calls
Call completion to busy subscribers
Malicious call identification
Sistemas de Telecomunicações II - 3.93
Engenharia de Comunicações - 2006/07
ISDN user part
• ISUP signalling procedures
–
–
–
–
Address signalling
Basic procedures
Signalling methods
Interworking
• Capabilities supported
– Internationally applicable class
– National use class
• Services assumed from the Message Transfer Part (MTP)
• End-to-end signalling
–
–
SCCP method of end-to-end signalling
Pass-along method of end-to-end signalling
• Future enhancements and compatibility procedure
Sistemas de Telecomunicações II - 3.94
Engenharia de Comunicações - 2006/07
Basic call control and signalling procedures
•
•
•
•
•
•
•
•
•
•
Successful call set‑up
Unsuccessful call set‑up
Normal call release
Suspend, resume
Signalling procedures for
connection type allowing
fallback
Propagation delay
determination procedure
Echo control signalling
procedures
Network features
Abnormal conditions
ISDN user part signalling
congestion control
•
•
•
•
•
•
•
•
•
•
Automatic congestion control
Unequipped circuit identification
code message (national use)
ISDN user part availability
control
MTP pause/resume
Overlength messages
Support for Temporary Alternative
Routing (TAR)
Hop counter procedure
Call collect request procedure
Support for hard to reach network
management functions
Calling geodetic location
procedure
Sistemas de Telecomunicações II - 3.95
Engenharia de Comunicações - 2006/07
Signalling Connection Control Part
The overall objectives of the signalling connection control
part are to provide the means for:
– Logical signalling connections within the Signalling System No.
7 network;
– A transfer capability for network service data units with or
without the use of logical signalling connections.
Functions of the SCCP are also used for the transfer of
circuit related and call related signalling information of
the ISDN user part with or without setup of end-to-end
logical signalling connections.
Sistemas de Telecomunicações II - 3.96
Engenharia de Comunicações - 2006/07
Functional diagram for the SCCP
The Signalling Connection Control Part is described in terms of:
•Services provided by the SCCP;
•Services assumed from the MTP;
•Functions of the SCCP.
Sistemas de Telecomunicações II - 3.97
Engenharia de Comunicações - 2006/07
Signalling Connection Control Part
Functions provided
by the SCCP
Connection-oriented functions
Functions for temporary
signalling connections
Functions for permanent
signalling connections
Connectionless service functions
Management functions
Lower boundary
of the SCCP MTP-SAP
MTP-primitives and parameters
TRANSFER
PAUSE
RESUME
STATUS
Notification of completion
of MTP restart
procedure
Routing and translation
functions
Sistemas de Telecomunicações II - 3.98
Engenharia de Comunicações - 2006/07
Transaction Capabilities Application Part
• The overall objective of Transaction Capabilities is to
provide the means for the transfer of information between
nodes, and to provide generic services to applications,
while being independent of any of these.
• Transaction Capabilities in a Signalling System No. 7
network should be considered for use between:
– Exchanges;
– An exchange and a network service centre (e.g. database, specialized facility unit,
OA&M Centre);
– Network service centres.
• Applications recognized as TC-users:
– Mobile service application (e.g. location of roamers);
– Registration, activation and invocation of supplementary services involving
specialized facility units (e.g. freephone service, credit card service);
– Non-circuit control-related exchange of signalling information (e.g. closed user
group, look-ahead procedure);
– Operation and maintenance applications (e.g. query/response).
Sistemas de Telecomunicações II - 3.99
Engenharia de Comunicações - 2006/07
Transaction Capabilities Application Part
•
Used to control non-circuit-related communications between two
or more signalling nodes
•
Interfaces between SCCP and TCAP
– Presentation layer
– Session layer
– Transport layer
•
Original implementations
– calling card
– 800-number applications
Sistemas de Telecomunicações II - 3.100
Engenharia de Comunicações - 2006/07
TC realization of Remote Operations
Sistemas de Telecomunicações II - 3.101
Engenharia de Comunicações - 2006/07
SS No. 7 management
TMN
functional
reference
model
Sistemas de Telecomunicações II - 3.102
Engenharia de Comunicações - 2006/07
GAT protocol architecture
Bearer-independent N-ISDN
(DSS1 & SS7)
Sistemas de Telecomunicações II - 3.103
Engenharia de Comunicações - 2006/07
GAT protocol architecture
Bearer-related N-ISDN
(DSS1 & SS7)
Sistemas de Telecomunicações II - 3.104
Engenharia de Comunicações - 2006/07
GAT protocol architecture
Bearer-related N-ISDN
(DSS2 & SS7)
Sistemas de Telecomunicações II - 3.105
Engenharia de Comunicações - 2006/07
Interworking of Signalling System No. 7 (TUP) to No. 5
Sistemas de Telecomunicações II - 3.106
Engenharia de Comunicações - 2006/07
Interworking of Signalling System No. 7 (TUP) to R2
Sistemas de Telecomunicações II - 3.107
Engenharia de Comunicações - 2006/07
International and national
signalling networks
Sistemas de Telecomunicações II - 3.108
Engenharia de Comunicações - 2006/07
Signalling between an International Switching Centre
and a digital interface to an ISDN satellite subnetwork
ISC - International Switching Centre
SCM - Satellite Connection Manager
Sistemas de Telecomunicações II - 3.109
Engenharia de Comunicações - 2006/07
Signalling interface definition
Protocol architecture
Sistemas de Telecomunicações II - 3.110
Engenharia de Comunicações - 2006/07
Call set-up procedures
NOTES
ACM - Address Complete Message
ANM - ANswer Message
IAM - Initial Address Message
1 This entire process is considered part of circuit selection, from ISUP protocol
perspective.
2 Instead of through-connect after ISIP set-up confirm, the exchange may
perform continuity check according to clause 7/Q.724 and then through
connect.
3 ACM/ANM may be replaced by CON message.
4 CPG may occur between ACM and ANM.
Sistemas de Telecomunicações II - 3.111
Engenharia de Comunicações - 2006/07
Transmission delays using satellite and
terrestrial message handling facilities
Sistemas de Telecomunicações II - 3.112