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6. Next Generation Networks 6.1. Transition to NGN 6.2. Key drivers of NGN development 6.3. Evolution of networks

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Title: 6. Next Generation Networks 6.1. Transition to NGN 6.2. Key drivers of NGN development 6.3. Evolution of networks


1
6. Next Generation Networks6.1. Transition to
NGN6.2. Key drivers of NGN development 6.3.
Evolution of networks architecture to NGN 6.4.
NGN architecture 6.5. Main NGN protocols and
building blocks
2
6.1. Transition to NGN First wave
  • Growth of Internet and other IP-based networks
    with their
  • requirements for bandwidth and capacity has
    driven rapid
  • innovation in telecommunication access and
    transport networks
  • Examples
  • leveraging copper wire last-mile networks
    through digital subscriber line (DSL)
    technologies
  • re-architecturing of cable networks to support
    IP services
  • advances in optical networking technologies
    (e.g. PON)

3
Convergence of Telephony World and Internet World
4
Transition to NGN Second wave
  • Ongoing trend towards integration
    interoperability of IP-
  • based and PSTN network services and applications
  • Emergence of differentiated Quality of Service
    IP-based services
  • Managed end-to-end performance needed for new
    applications
  • requiring real-time traffic (e.g., video, voice)
  • New network management, QoS, traffic
    engineering, pricing
  • accounting models

5
Transition to NGN Third wave
  • Evolution of current PSTN, mobile, wireless and
  • IP-based networks to unified Next Generation
    Networks
  • providing both Internet and carrier-grade
    telecommunications
  • networks and services offerings with QoS
  • Transition to Third wave
  • Ubiquitous Pervasive Networks
  • anybody, anytime, anywhere
  • Global Information Infrastructure (GII) ITU,
    1995
  • EII ETSI Project (1995)
  • ETSI 3GPP (1998)
  • 3GPP activity (FMC and IMS development)
  • TISPAN Project (ETSI, 2003)
  • TISPAN - Telecoms Internet converged
    Services Protocols for Advanced Networks
  • ITU NGN 2004 Project
  • Y.1xx ITU-T SG 13 NGN Architecture,
    Evolution and Convergence

6
One unified network for everything
Transition to NGN Third wave
Today
Tomorrow
Internet
Telephone network
IP-Network
Mobile radio network
  • Multimedia Access - Advantages
  • easy to handle
  • reliable
  • mobile

7
The Unified NetworkThe Vision
Situation Today
Target Solution
Voice Fix and Mobile
The Unified Multi Service Network
FR
IP
...
ATM
8
The Unified NetworkThe Data Migration
Voice
The Unified Multi Service Network
FR
IP
...
ATM
9
The Unified NetworkThe Voice Migration
Voice
The Unified Multi Service Network
FR
IP
...
A new network concept supporting voice in a
packetized environment is required The Next
Generation Network
ATM
10
ITU-T definition of NGN (Y.2001, Feb 2004)
  • A Next Generation Network (NGN) is a
    packet-based network
  • able to provide services including
    Telecommunications Services
  • and able to make use of multiple broadband,
    QoS-enabled
  • transport technologies and in which
    service-related functions
  • are independent from underlying transport-related
    technologies.
  • It offers unrestricted access by users to
    different service
  • providers. It supports generalized mobility which
    will allow
  • consistent and ubiquitous provision of services
    to users.
  • One of the primary goals of NGN is to provide a
    common, unified,
  • and flexible service architecture that can
    support multiple types of
  • services over multiple types of transport
    networks.

11
NGN is the public packet-based network with the
following main features
  • Layered architecture
  • Open interfaces between the layers and all other
    networks
  • Seamless control of multiple transport
    technologies
  • Centralized intelligence

12
NGN Characteristics
  • The NGN is characterized by the following
    fundamental aspects
  • Packet-based transfer in the core NGN network
  • Support for a wide range of services,
    applications and mechanisms
  • (including real time/ streaming/ non-real time
    services and multi-media)
  • Independence of service-related functions from
    underlying transport
  • technologies
  • Separation of control functions among bearer
    capabilities, call/session, and
  • applications/services
  • Broadband capabilities with required end-to-end
    QoS
  • Interworking with legacy networks via open
    interfaces
  • Generalized mobility
  • Unrestricted access by users to different service
    providers
  • Services convergence between Fixed/Mobile
  • Compliance with all Regulatory requirements, for
    example concerning emergency communications,
    security/privacy, etc.

13
6.2. Key drivers of NGN development
  • Short Term objective Create new revenue
    possibilities
  • Removal of boundaries between voice and data
    opens the way to new kind of services
  • Can be realized relatively quickly with limited
    investments
  • Long Term objective Realize cost savings
  • Simpler network
  • More efficient network
  • Cheaper network components
  • Full benefit only realized when all separate
    networks have fully migrated towards to the
    target solution

14
Key drivers technologies and services
Next Generation Network
15
NGN key drivers From IP Technology to User and
Application Centric
  • User demands
  • easiness to use and personalization of services
  • seamless service regardless of the access
    technology
  • a beautiful garden offering valuable services
    with security
  • openness to the entire Community
  • Operator challenges need to be addressed
  • need to manage complexity to deliver simplicity
  • platform for convergence of services and
    technologies
  • support of different device and access
    technologies
  • revenue opportunities by mobility and nomadicity,
    worldwide use
  • support migration from existing technologies

16
NGN services
17
NGN Services
  • Voice Telephony NGN will likely need to support
    various existing voice telephony
  • services (e.g., Call Waiting, Call Forwarding,
    3-Way Calling, various IN features,
  • various Centrex features and etc.).
  • Data Services Allows for the real-time
    establishment of connectivity between
  • endpoints, along with various value-added
    features
  • Multimedia Services Allows multiple parties
    to interact using voice, video, and/or
  • data.
  • Virtual Private Networks (VPNs) Voice VPNs
    improve the interlocation networking
  • capabilities of businesses by allowing large,
    geographically dispersed organizations to
  • combine their existing private networks with
    portions of the PSTN, thus providing
  • subscribers with uniform dialing capabilities.
  • .

18
NGN Services
  • Public Network Computing (PNC) Provides public
  • network-based computing services for businesses
    and
  • consumers.
  • Unified Messaging Supports the delivery of
    voice mail, email,
  • fax mail, and pages through common interfaces.
  • Information Brokering Involves advertising,
    finding, and
  • providing information to match consumers with
    providers.
  • E-Commerce Allows consumers to purchase goods
    and
  • services electronically over the network. Home
    banking and
  • home shopping fall into this category of
    services. This also
  • includes business-to-business applications

19
NGN Services
  • Call Center/Web Contact Services A subscriber
    could place a call to a call/Web contact center
    agent by clicking on a Web page.
  • Interactive gaming Offers consumers a way to
    meet online and establish interactive gaming
    sessions (e.g., video games).
  • Distributed Virtual Reality Refers to
    technologically generated representations of real
    world events, people, places, experiences, etc.,
  • Home Manager With the advent of in-home
    networking and intelligent appliances, these
    services could monitor and control home security
    systems, energy systems, home entertainment
    systems, and other home appliances.

20
Applications
  • VoIP
  • Web Browsing
  • Chat
  • Instant Messaging
  • WAP Browsing
  • Multimedia Messaging
  • VoD Movies/Gaming/News/Sports/Training
  • Video Telephony
  • Video Broadcasting
  • Video Conferencing
  • Video Collaboration
  • IP PBX/Centrex
  • Email

21
NGN Today Facing the Multi-Application/Multi-Acc
ess Challenge
22
6.3. Evolution of networks architecture to NGN
  • The unified network will use packet-based
    technology as the common transport mechanism
  • Data is the fastest growing segment due to
  • Success of Internet
  • Growing use of E-mail
  • Growing data traffic between business users
  • Data should be handled in the most efficient way
  • Packet technology is the best way to transport
    data
  • Packet technology is only technology that allows
    simultaneous delivery of different information
    streams towards one and the same end-point on one
    single connection

23
  • Evolution of network architecture
  • Traditional telephony - Circuit switch based PSTN

24
Evolution of network architecture
Circuit Switched PSTN Packet Switched IP
network (VoIP Gateway) SG Signaling
gateway MGC Media gateway controller MG Media
gateway
25
Evolution of network architecture
  • Completely IP-oriented network

26
Convergence of network technologies and media
Nx64 kbps
27
6.4. NGN architecture
Management
System Management Servers
Application Servers
Applications
Softswitches Signaling gateways
Control
Packet Network
Core
MediaGateway
Mobile
PSTN
MediaGateway
Edge
Broadband
UTRAN
Access
CO
DSL
WLL
Cable
Mobile Users
Remote Office/SOHO
Enterprise Customers
ResidentialUsers
28
NGN architecture - NGN functional model
Application/Management Part
Application Servers Management Servers
Open Services Interfaces/API

Session Part (Call control)
Softswitches
Media Gateway Control

Transport Layer
Media Gateways
API - Application Programming Interface
29
NGN architecture
Services
Transport
30
ITU-T NGN architecture (Y.1001) and corresponding
protocols
IP Network
IW Functions
PSTN/ISDN
  • Softswitch includes MGC, SG
  • Media Gateway is protocol converter
  • Media Gateway Controller is master
  • controller of a media gateway
  • Intelligent Database - Network directory,
  • Billing, Call records

Intelligent Database (ID)
.
.
ID/SG
ID/MGC
API
.
.
Signaling Gateway (SG)
H.323/SIP/SIP-T/ SIGTRAN
.
CC7/SS7 ISUP
SG/MGC
MG Controller (MGC)
.
MGC/MGC
.
MGC/MG
MGCP/Megaco(H.248)
.
.
Media Gateway (MG)
RTP Packet Flow (Voice/Data/MM)
TDM Flow (Voice)
31
6.5. Main NGN protocols and building blocks
32
Main control protocols
  • Call Control (Session Control)
  • The ability of a network element to establish new
    calls.
  • A call in the next generation network can be
    viewed as
  • a session in which the session establishes either
    a voice
  • conversation or, ultimately, a multimedia (audio
    plus video)
  • stream.
  • There are two primary call control protocols
    unique to
  • packet-based networks
  • H.323
  • SIP

33
H.323, ITU-T
  • H.323 - first call control standard for
    multimedia networks.
  • Was adopted for VoIP by the ITU in 1996
  • H.323 is actually a set of recommendations that
    define how
  • voice, data and video are transmitted over
    IP-based networks
  • The H.323 recommendation is made up of multiple
    call control
  • protocols. The audio streams are transacted
    using the RTP/RTCP
  • In general, H.323 was too broad standard without
    sufficient
  • efficiency. It also does not guarantee
    business voice quality

34
SIP - Session Initiation Protocol, IETF (Internet
Engineering Task Force)
  • SIP - standard protocol for initiating an
    interactive user session that involves multimedia
    elements such as video, voice, chat, gaming, and
    virtual reality. Protocol claims to deliver
    faster call-establishment times.
  • SIP works in the Session layer of IETF/OSI model.
    SIP can establish multimedia sessions or Internet
    telephony calls. SIP can also invite participants
    to unicast or multicast sessions.
  • SIP supports name mapping and redirection
    services. It makes it possible for users to
    initiate and receive communications and services
    from any location, and for networks to identify
    the users wherever they are.

35
SIP - Session Initiation Protocol, IETF
  • SIP client-server protocol, Rq from clients, Rs
    from servers. Participants are identified by SIP
    URLs. Requests can be sent through any transport
    protocol, such as UDP, or TCP.
  • SIP defines the end system to be used for the
    session, the communication media and media
    parameters, and the called party's desire to
    participate in the communication.
  • Once these are assured, SIP establishes call
    parameters at either end of the communication,
    and handles call transfer and termination.
  • The Session Initiation Protocol is specified in
    IETF Request for Comments (RFC) 2543.

36
IN Control
  • Feature servers provide IN control with legacy
    central
  • offices and Softswitches.
  • INAP (Intelligent Network Application Part) - a
    member
  • of the family of SS7 application protocols.
  • Additional IN protocols have also been developed
  • for mobile networks (e.g. GSM-CAMEL).

37
Gateway control
  • The target of the Gateway control - to enable a
    simple
  • media gateway implementation with intelligence
  • centralized on a media gateway controller (which
    is also
  • called a call agent or a Softswitch)
  • Two gateway control protocols
  • Media Gateway Control Protocol (MGCP) as the de
  • facto standard
  • H.248/Megaco as the ITU and IETF approved
    standard.

38
MGCP/Megaco/H.248
  • MGCP - Media Gateway Control Protocol, IETF
    Telcordia (formerly Bellcore)/Level 3/Cisco
  • MGCP control protocol that specifically
    addresses the control of media gateways
  • Megaco/H.248 (IETF, ITU) - standard that combines
    elements of the MGCP and the H.323, ITU (H.248)
  • The main features of Megaco - scaling (H.323) and
    multimedia conferencing (MGCP)

39
Media Control
  • Media control is a form of device control used
    for network
  • elements that are specialized for advanced media
    processing.
  • Media control includes instructions to play and
    record voice
  • files, collect and generate tones (including DTMF
    touch-tones),
  • establish N-way conferences, perform fax
    conversions, generate
  • text-to-speech, and perform speech recognition.

40
Application Program Interface
  • API - routing, billing, call control, and media
    control on
  • the feature server and application server.
  • The goal of the APIs is to enable
  • 1. Service logic that is independent of network
    protocols,
  • network deployment architecture, and reference
    element
  • architecture to meet the service provider
    requirement for
  • service ubiquity
  • 2. Services that scale from an entry level
    integrated
  • solution to a distributed network deployment
    without
  • modifications, meeting the service provider
    requirement
  • for low cost infrastructure

41
Main transport protocols
  • Real-Time Transport Protocol (RTP) and Real-Time
    Control Protocol (RTCP)
  • RTP - for end-to-end network transport of
    communications services requiring
  • real-time data (i.e., audio and/or video).
  • Real-Time Control Protocol (RTCP) for data
    transport monitoring
  • RTP and RTCP are designed to be independent of
    the underlying network layers (e.g.,
  • UDP/IP, MPLS, or ATM).
  • RTP does not address resource reservation nor
    does it guarantee quality-of-service
  • (QoS).
  • Resource Reservation Setup Protocol (RSVP)
  • Multi-Protocol Label Switching (MPLS)
  • RTP routing over MPLS sessions

42
NGN architecture possible NGN configuration
Network Manager
Application Server
SNMP
RADIUS
API (Parlay, LDAP)
Softswitch
SIP/SIP-T H.323/BICC
SG
SIGTRAN
SG
SS7 ISUP
SIGTRAN
ISUP
Softswitch
SIP
MGC
MGCP/Megaco/H.248
Gatekeeper/ Proxy Server
Media Gateway
Media Gateway
Core IP Network (QoS)
?.323/ IP Network
43
B. NGN building blocks
  • Media Gateway - protocol converter
  • Media Gateway Controller - master controller of a
    media gateway
  • Softswitch MGC SG
  • Signaling Gateway
  • Application Server Information Database (ID) -
    Network directory, Billing, Call records,
    Authentication, authorization, and accounting
    (AAA)
  • Network Manager Operation, Administration,
    Management (OAM) provides network elements
    management from a centralized web interface

44
Media Gateway (IETF RFC 3015)
  • Media gateway (MG) protocol converter between
    different types
  • of networks (Example MG between
    circuit-switched voice
  • network - TDM flows, and the IP network - RTP
    packet flows.)
  • MG processes incoming calls via requests to the
    Application
  • Server using HTTP.
  • The media gateway (MG) terminates IP and
    circuit-switched
  • traffic. MGs relay voice, fax, modem and ISDN
    data traffic over the
  • IP network using Quality of Service enabled IP
    technology.

45
Media Gateway (IETF RFC 3015)
  • All types of traffic (voice, data, video)
  • Control (from Media Gateway Controller) MGCP,
    Megaco/H.248
  • Interfaces STM-1to transport network, E1 to
    PSTN Eth-Fast/Gb to
  • IP network
  • Voice Packetization/Compression (Codecs ITU-T
    G.711, G.723.1, G.726, G.729A
  • Echo cancellation ITU-T G.165, G.168
  • QoS via DiffServ and ToS bits marking
  • Mapping addresses E.164 IP address

46
Softswitch
  • Signaling Gateway
  • Signaling Gateway (SG) offers a consolidated
    signaling
  • interface - SS7 signaling point for the NGN
    platform.
  • Also, SG supports a SIGTRAN interface (IETF SS7
    telephony
  • signaling over IP) as well as IP Proxy functions
    (SIP).
  • Media Gateway Controller
  • MGC acts as the master controller of a media
    gateway
  • Supervises terminals attached to a network
  • Provides a registration of new terminals
  • Manages E.164 addresses among terminals

47
Signaling Gateway Function
  • Several millions BHCA
  • Several hundreds controlled trunk ports
  • Control MGCP, MEGACO, SIP
  • Signaling ISUP, H.323, SIP, SIP-T, INAP, SIGTRAN
  • Mgmt SNMP

IP Signaling
SS7 Signaling
SIGTRAN
ISUP
IP Network
PSTN
Signaling Gateway
48

Application Server
  • Application server provides the applications
    (i.e., service logic) for new and
  • innovative services such as unified messaging,
    conferencing, speech dial tone,
  • and multimedia messaging services. Application
    servers are typically based on
  • advanced Java tool environments that provide
    multi-modal integration of voice
  • and data.
  • Application Server generates application
    documents (VoiceXML pages) in
  • response to requests from the Media Gateway via
    the internal Ethernet
  • network.
  • The application server leverages a web
    application infrastructure to interface
  • with data stores (messages stores, user profile
    databases, content servers)
  • to generate documents (e.g., VoiceXML pages).
  • AS provide interoperability between applications
    like WAP, HTML, and voice
  • allowing the end user to simultaneously input
    voice command and receive
  • presentation via WAP or HTML.

49
Appendix A Parlay
  • Parlay is an evolving set of specifications
    for industry-standard application programming
    interfaces (APIs) for managing network "edge"
    services
  • call control
  • messaging
  • content-based charging.
  • Parlay specifications are being developed by
    the Parlay Group, a consortium of member
    companies that include ATT, BT, Cisco, IBM,
    Lucent, Microsoft, Nortel Networks, and others.
  • Use of the Parlay specifications is expected
    to make it easier to add new cross-platform
    network applications so that users need not
    depend solely on the proprietary offerings of
    carriers.
  • The Parlay Group is not a standards group
    itself, but sees itself as a facilitator of
    needed interfaces. Application program interfaces
    are or will be defined for

50
Parlay
  • Authentication
  • Integrity management
  • Operations, administration, and maintenance
    (OAM)
  • Discovery (of the closest provider of a service)
  • Network control
  • Mobility
  • Performance management
  • Audit capabilities
  • Generic charging and billing
  • Policy management
  • Mobile M-commerce/E-commerce
  • Subscriber data/user profile/virtual home
    environment (VHE)
  • The Parlay APIs are said to complement and
    encourage use of the Advanced Intelligent Network
    (AIN) protocols.

51
Appendix B Application level protocols
  • A. LDAP (Lightweight Directory Access Protocol)
  • LDAP (Lightweight Directory Access Protocol) is a
    software protocol for enabling anyone to locate
    organizations, individuals, and other resources
    such as files and devices in a network, whether
    on the public Internet or on a corporate
    Intranet.
  • LDAP is a "lightweight" (smaller amount of code)
    version of Directory Access Protocol (DAP), which
    is part of X.500, a standard for directory
    services in a network. LDAP is lighter because in
    its initial version it did not include security
    features.
  • LDAP originated at the University of Michigan and
    has been endorsed by at least 40 companies.
    Netscape includes it in its latest Communicator
    suite of products. Microsoft includes it as part
    of what it calls Active Directory in a number of
    products including Outlook Express. Novell's
    NetWare Directory Services interoperates with
    LDAP. Cisco also supports it in its networking
    products.

52
B. LDAP
  • In a network, a directory tells you where in the
    network something is located. On TCP/IP networks
    (including the Internet), the domain name system
    (DNS) is the directory system used to relate the
    domain name to a specific network address (a
    unique location on the network). However, you may
    not know the domain name. LDAP allows you to
    search for an individual without knowing where
    they're located (although additional information
    will help with the search).
  • An LDAP directory is organized in a simple "tree"
    hierarchy consisting
  • of the following levels
  • The root directory (the starting place or the
    source of the tree), which branches out to
  • Countries, each of which branches out to
  • Organizations, which branch out to
  • Organizational units (divisions, departments,
    and so forth), which branches out to (includes an
    entry for) Individuals (which includes people,
    files, and shared resources such as printers)
  • An LDAP directory can be distributed among many
    servers. Each server can have a replicated
    version of the total directory that is
    synchronized periodically. An LDAP server is
    called a Directory System Agent (DSA). An LDAP
    server that receives a request from a user takes
    responsibility for the request, passing it to
    other DSAs as necessary, but ensuring a single
    coordinated response for the user.

53
B. Authentication, Authorization, Accounting
(AAA)
  • Authentication, Authorization, Accounting (AAA)
    is a term for a framework for intelligently
    controlling access to computer resources,
    enforcing policies, auditing usage, and providing
    the information necessary to bill for services.
    These combined processes are considered important
    for effective network management and security.
  • As the first process, authentication provides a
    way of identifying a user, typically by having
    the user enter a valid user name and valid
    password before access is granted. The process of
    authentication is based on each user having a
    unique set of criteria for gaining access. The
    AAA server compares a user's authentication
    credentials with other user credentials stored in
    a database. If the credentials match, the user is
    granted access to the network. If the credentials
    are at variance, authentication fails and network
    access is denied.
  • Following authentication, a user must gain
    authorization for doing certain tasks. After
    logging into a system, for instance, the user may
    try to issue commands. The authorization process
    determines whether the user has the authority to
    issue such commands. Simply put, authorization is
    the process of enforcing policies determining
    what types or qualities of activities, resources,
    or services a user is permitted. Usually,
    authorization occurs within the context of
    authentication. Once you have authenticated a
    user, they may be authorized for different types
    of access or activity.

54
B. Authentication, Authorization, Accounting (AAA)
  • The final term in the AAA framework is
    accounting, which measures the resources a user
    consumes during access. This can include the
    amount of system time or the amount of data a
    user has sent and/or received during a session.
    Accounting is carried out by logging of session
    statistics and usage information and is used for
    authorization control, billing, trend analysis,
    resource utilization, and capacity planning
    activities.
  • Authentication, authorization, and accounting
    services are often provided by a dedicated AAA
    server, a program that performs these functions.
    A current standard by which network access
    servers interface with the AAA server is the
    Remote Authentication Dial-In User Service
    (RADIUS).

55
C. RADIUS
  • Remote Authentication Dial-In User Service
    (RADIUS) is a client/server protocol and software
    that enables remote access servers to communicate
    with a central server to authenticate dial-in
    users and authorize their access to the requested
    system or service. RADIUS allows a company to
    maintain user profiles in a central database that
    all remote servers can share. It provides better
    security, allowing a company to set up a policy
    that can be applied at a single administered
    network point. Having a central service also
    means that it's easier to track usage for billing
    and for keeping network statistics. Created by
    Livingston (now owned by Lucent), RADIUS is a de
    facto industry standard used by a number of
    network product companies and is a proposed IETF
    standard.

56
Appendix C. Additional NGN signaling protocols
  • SIP-T
  • SIGTRAN
  • BICC

57
A. SIP-T
  • SIP-T (SIP for telephones) is a mechanism that
    uses SIP to facilitate the interconnection of the
    PSTN with IP. SIP-T defines SIP functions that
    map to ISUP interconnection requirements.
  • This is intended to allow traditional IN-type
    services to be seamlessly handled in the Internet
    environment. It is essential that SS7 information
    be available at the points of PSTN
    interconnection to ensure transparency of
    features not otherwise supported in SIP. SS7
    information should be available in its entirety
    and without any loss to the SIP network across
    the PSTN-IP interface.

58
B. SIGTRAN
  • SIGTRAN (for Signaling Transport) is the standard
    Telephony Protocol used to transport Signaling
    System 7 signals over the Internet. SS7 signals
    consist of special commands for handling a
    telephone call.
  • The IETF Signaling Transport working group has
    developed SIGTRAN to address the transport of
    packet-based PSTN signaling over IP Networks,
    taking into account functional and performance
    requirements of the PSTN signaling. For
    interworking with PSTN, IP networks will need to
    transport signaling such as Q.931 or SS7 ISUP
    messages between IP nodes such as a Signaling
    Gateway and Media Gateway Controller or Media
    Gateway. Applications of SIGTRAN include Internet
    dial-up remote access and IP telephony
    interworking with PSTN.

59
B. SIGTRAN
  • A telephone company switch transmits SS7 signals
    to a SG. The gateway,
  • in turn, converts the signals into SIGTRAN
    packets for transmission over IP
  • to either the next signaling gateway.
  • The SIGTRAN protocol is actually made up of
    several components (this is
  • what is sometimes referred to as a protocol
    stack)
  • standard IP
  • common signaling transport protocol (used to
    ensure that the data required for signaling is
    delivered properly), such as the Streaming
    Control Transport Protocol (SCTP)
  • adaptation protocol that supports "primitives"
    that are required by another protocols.

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C. Bearer Independent Call Control (BICC)
  • Bearer Independent Call Control (BICC) is a
    signaling protocol based on N-ISUP that is used
    to support NB-ISDN service over a BB backbone
    network without interfering with interfaces to
    the existing network and end-to-end services.
    Specified by the ITU-T in recommendation Q.1901,
    BICC was designed to be fully compatible with
    existing networks and any system capable of
    carrying voice messages. BICC supports narrowband
    ISDN services independently of bearer and
    signaling message transport technology.

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C. Bearer Independent Call Control (Cntd.)
  • ISUP messages carry both call control and
    bearer control information, identifying the
    physical bearer circuit by a Circuit
    Identification Code (CIC). However, CIC is
    specific to time-division multiplexed TDM
    networks. BICC was developed to be interoperable
    with any type of bearer, such as those based on
    asynchronous transfer mode ATM and IP
    technologies, as well as TDM.
  • BICC separates call control and bearer
    connection control, transporting BICC signaling
    independently of bearer control signaling. The
    actual bearer transport used is transparent to
    the BICC signaling protocol - BICC has no
    knowledge of the specific bearer technology.

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C. Bearer Independent Call Control (Cntd.)
  • The ITU announced the completion of the second
    set of BICC protocols (BICC Capability Set 2, or
    CS 2) in July 2001 these are expected to help
    move networks from the current model - which is
    based on public-switching systems - to a
    server-based model. The BICC deployment
    architecture comprises a proxy server and a media
    gateway to support the current services over
    networks based on circuit-switched, ATM, and IP
    technologies, including third-generation
    wireless.
  • The completion of the BICC protocols is an real
    and important ITU step toward broadband
    multimedia networks, because it will enable the
    seamless of circuit-switched TDM networks to
    high-capacity broadband multimedia networks. The
    3GPP has included BICC CS 2 in the UMTS release
    4. Among the future ITU-T plans for BICC are the
    inclusion of more advanced service support and
    more utilization of proxies, such as the SIP
    proxy.
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