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Programmable Architecture for the Creation and Seamless Control of Hybrid Services. Constant Gbaguidi Swiss Federal Institute of Technology (Lausanne). Outline. Problem Statement Need for a creation and control architecture, with well-defined service components Our approach - PowerPoint PPT Presentation
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Programmable Architecture for the Creation and Seamless Control of
Hybrid Services
Constant Gbaguidi
Swiss Federal Institute of Technology (Lausanne)
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
2
Outline• Problem Statement
– Need for a creation and control architecture, with well-defined service components
• Our approach– Service-centricity, as opposed to network- and end-system-centricity
– Programmability: changing the behavior of a system through an API
– Smooth migration from existing infrastructures to more “futuristic” ones
– Use of tools that can be understood by Telecom as well as Internet people
• Case studies– Voice-Access-to-Content, Closed User Group (CUG)
• Related Work
• Conclusion
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
3
Scope of Hybrid Services
Telecommunication services
Internet servicesHybrid Services
ConferenceIN VPNVoice MailCall ForwardingMobility
ConferenceInternet VPNEmail and VoicemailChat (IRC)Content services (Web)Electronic commerce
Voice Access to ContentTelecommutingTeleconferenceIntegrated VPN
• Hybrid services are not re-implementations of existing services
• They allow access to services already implemented on either telecommunication or IP networks
• They allow unique implementation of services, which can still be accessed from any network
• They pave the road to the provision of future services that do not rest on only one network
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
4
Problem Statement
• How to create and control hybrid services?– Control:
• Provision of a service binding layer that permits passing service control information across networks (Today we have interoperability at the media transfer and media control layers)
– Creation: • Specification of components out of which services can be built (The components must
make sense to both Telecom and Internet communities)
• Mapping of the components onto the service system elements
IP network PSTN
H.323 gatewayCaller Callee
Freephone service logic
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
5
An Overview of Our Solution
ServiceCreation
Environment
Internet
PSTN(and N-ISDN)
CellularNetwork
API
API: Application Programming Interface
Java Service Layer
Programmability
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
6
API
API: Application Programming Interface
Java Service Layer
ServiceCreation
Environment
Programmability
Terminal Network Node Control Server Gateway
SwitchRouterWireless LAN NodeGSM Base Station
H.323 gatewayFirewall
IN Service Ctrl PointH.323 gatekeeperDHCP serverDNS
WorkstationSmart phone
An Overview of Our Solution (cont’d)
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
7
Service Creation Environment Service Factory
Service Instance
Beans Archive
1. Identify service components
SS SSSS
ST/S2
ST/S1
SN/S1
SC/S2
SC/S1
SG/S1
Controller Controller Controller Controller
Terminal Network Node Control Server Gateway
Java Service Layer
Service binding Service binding Service binding Service binding
CT/Si: Subsystem on Terminal for Service #iCN/Si: Subsystem on Network node for Service #iCC/Si: Subsystem on Control server for Service #ICG/Si: Subsystem on Gateway for Service #iSS: Service Subsystem
3. Build the binding
layer
Architecture of Our Solution
2. Download the components
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
8
1. Service Modeling: A Way to Identify Components
A Service is composed of features, each of which is associated with an object model. Classes in the models are the sought components
Customer Service
Feature
defines *
Charging Call control Connectivity User Interaction
involvesinteracts with
Address Translation
Security
Inheritance
Composition
Object class
Association class
Key:
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
9
1. Example: Address Translation
• End-system is a generic concept that embraces terminals, gateways, information converters, multipoint control units, etc.
• The user makes use of a device (e.g., a Smart Card) that has an address
• The user may have a higher level address (e.g., email address)
• The user can bind addresses with one another
Device Device Address
User Address Binding
has1 1
1
manages
uses1
*
End-system
*
*User Address
Device Address
Address
User Address
1
1
has
Inheritance
Composition
Object class
Association class
Key:
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
10
Service Creation Environment Service Factory
Service Instance
Beans Archive
1. Identify service components
SS SSSS
ST/S2
ST/S1
SN/S1
SC/S2
SC/S1
SG/S1
Controller Controller Controller Controller
Terminal Network Node Control Server Gateway
Java Service Layer
Service binding Service binding Service binding Service binding
CT/Si: Subsystem on Terminal for Service #iCN/Si: Subsystem on Network node for Service #iCC/Si: Subsystem on Control server for Service #ICG/Si: Subsystem on Gateway for Service #iSS: Service Subsystem
3. Build the binding
layer
Architecture of Our Solution
2. Download the components
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
11
2. Component Download
0. put persistent component c: C
on server Web serverService instance
Controller
1. execute(C c, URL url)
2. get c
3. configure underlying element
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
12
Service Creation Environment Service Factory
Service Instance
Beans Archive
1. Identify service components
SS SSSS
ST/S2
ST/S1
SN/S1
SC/S2
SC/S1
SG/S1
Controller Controller Controller Controller
Terminal Network Node Control Server Gateway
Java Service Layer
Service binding Service binding Service binding Service binding
CT/Si: Subsystem on Terminal for Service #iCN/Si: Subsystem on Network node for Service #iCC/Si: Subsystem on Control server for Service #ICG/Si: Subsystem on Gateway for Service #iSS: Service Subsystem
3. Build the binding
layer
Architecture of Our Solution
2. Download the components
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
13
3. Service Binding Layer
System element interface
Enterprise components (e.g., RMI<->CORBA,
EJB)
Java RMI
Binding components(e.g., security, download)
Element
Element {openConnection,pauseConnection,
resumeConnection,releaseConnection,bindConnections,
transferConnection,handleEvent
}
e.g., TAPI, CallPath API, SS7
API, IN API
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
14
Element
Java Service Layer
Trigger-Event-Source
Trigger-Event-Listener(implements methods to handle the events caught)
Element
Network Node Gateway Control Server Terminal
Inheritance
3. A Way to Interface with Elements
Interruptions, APIs, SNMP, H.323, IN
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
15
1. fires
TriggerEvent
2. goes to
3. fires CnxAttemptEvent
CnxFailEvent6. fires
6. fires
7. goes to 4. goes to
5. creates
CnxCompleteEvent
7. goes to
8. creates
Service component
Event
Java Service Layer
Element
ConnectionFactory
Connection
ConnectionBinding
TriggerEventListener
Event Source
3. A Way to Interface with Elements (cont’d)
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
16
Service Creation Environment Service Factory
Service Instance
Beans Archive
1. Identify service components
SS SSSS
ST/S2
ST/S1
SN/S1
SC/S2
SC/S1
SG/S1
Controller Controller Controller Controller
Terminal Network Node Control Server Gateway
Java Service Layer
Service binding Service binding Service binding Service binding
CT/Si: Subsystem on Terminal for Service #iCN/Si: Subsystem on Network node for Service #iCC/Si: Subsystem on Control server for Service #ICG/Si: Subsystem on Gateway for Service #iSS: Service Subsystem
3. Build the binding
layer
Architecture of Our Solution
2. Download the components
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
17
Implementation Test-bed
• + Most elements of the test-bed can detect special services, by detecting prefixes in the numbers dialed
• - APIs existing on the elements are not easily customizable from an application
PABX H.323GW IP Network
Siemens Hicom 112
H.323GK
ISDN BRI
RADVision Elemedia H.323 stack
Java Service Layer
PABX controller GK controller Term. controller
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
18
Voice-Access-to-Email
PABX H.323GW IP Network
Siemens Hicom 112
Java Service Layer
H.323GK
ISDN BRI
RADVision
PABX controller GK controller Server controller
Accommodating server
Email server
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
19
Voice-Access-to-Email (cont’d)
• Start retrieving the mails : Email Retriever
• As long as nothing has come– play waiting message : User Interaction
• Parse the received mail : Email Parser – remove useless header fields (e.g., route information)
– remove useless tags (<FONT>, <BODY>, etc.)
• Convert the parsed file into speech: Microsoft Speech API (Java wrapper, JNI)
• Play the speech file over the network: Elemedia H.323 stack
• ~30s to read an email
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
20
H323 Call factory
Incoming H.323 messages
Outgoing H.323 messages
Call instances
Application
Email Retriever
Email Parser
Text-to-speech
Converter
User Interaction
Email Server
Voice-Access-to-Email (cont’d)
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
21
Voice-Access-to-W3
H323 Call factory
Incoming H.323 messages
Outgoing H.323 messages
Call instances
Application
Web site Retriever
HTML Parser
Text-to-speech
Converter
User Interaction
Web Server
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
22
Voice-Access-to-W3: HTML Parser
• Replace a link by an announcement like “Press 234 if you wanna learn more about this topic”
• Remove applet information
• Remove scripts
• A dedicated language would be a suitable solution but then all pages would have to be re-written!
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
23
Closed User Group
A B C D
PABX H.323GW IP Network
Siemens Hicom 112
Java Service Layer
H.323GK
ISDN BRI
RADVision
CUGS controller
CUG Server
Term. controller
E F
Feature: Confidential information passing between F and C while in a session with A, B, D and E
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
24
Learnings
• The proposed architecture can be used to enhance the service offerings of current platforms
• To fully take advantage of the architecture, we need APIs for the platform elements
• Service composability within the architecture has been illustrated
• Java is a good candidate
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
25
Related Work in the Internet
• GeoPlex (AT&T)
– 5 programmable elements:• Cores: mission-critical
databases and functions
• Hops: e.g., routers
• Gates: entrances to the GeoPlex network
• Stores: directories, event reports
• Peers: GeoPlex-enabled devices
• Internet-dependent, although some of the APIs can be re-used for other elements
SecureSecuretrusted-domaintrusted-domain
boundaryboundary
ConsumerConsumerNetworkNetwork
ConsumerConsumerNetworkNetwork
HopHop
StoreStore
TelephoneTelephoneNetworksNetworksTelephoneTelephoneNetworksNetworks
HopHop
HopHop
InternetInternetInternetInternet
ee ClientClientPeerPeer
ClientClientPeerPeer
Extended Extended NetworkNetwork
VideoVideoSvcSvc
CoreCore
GateGate
GateGate
GateGate
GateGate
GateGateGateGate
GateGate
GateGate
ee ClientClientPeerPeer
ClientClientPeerPeer
eeClientClientPeerPeer
ClientClientPeerPeer
Our solution is more generic and applicable to all technologies
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
26
Related Work in Telecommunications
• Intelligent Network (IN)– dumb terminals
– services as compositions of functional building blocks
– service logic controlled by Service Control Points (SCP)
• no service creation environment standardized
• building blocks are heavily defined
• limited distribution (functional approach!)
SSP SSP
SCP
(1) We propose a service creation environment based on a platform-independent language (i.e., Java)
(2) We use an object-oriented technique to find and specify service components
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
27
Related Work in Telecommunications (cont’d)
• Telecommunications Information Networking Architecture (TINA)
– goal: enhance the IN with distributed processing and integrate service provision and management
• heavyweight connection management (connection-oriented networks)
• building of service logic not emphasized
Serv. Sess. Mgr
Net. Cnx Mgr
Net. Elt. Mgr Net. Elt. Mgr
Computationalobject
Our solution provides a simple connection model and a technique to determine generic service components
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
28
Related Work in Telecommunications (cont’d)
• XBIND (Columbia University, NY)– same objectives as TINA, but with a
service-centric vision: programmability of end-systems considered
• ATM-oriented
• lack of a service model
(1) Our solution is both past- and future-proof: no specific technology in mind(2) We provide a service model that helps find service components using an object-oriented technique
Serv. Sess. Mgr
Net. Cnx Mgr
Net. Elt. Mgr
Net. Elt. Mgr
Device Mgr
Camera Mgr
Display Mgr
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
29
Related Work on Hybrid Services
• Computer-Telephony Integration (CTI)
– goal: be able to place and control telephone calls from a computer
– “IN” for corporate networks• deployment at the edge of the network, e.g., in enterprise networks: complex
services need also to look into the network
PABX
CTI LinkOur solution enables CTI to
look into the network in order to implement
sophisticated services
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
30
Related Work on Hybrid Services (cont’d)
• PSTN and Internet Interworking (PINT)
– enable a telephone call from an IP terminal to the PSTN
• data is transported over the PSTN
• no service control from the initiating IP terminal
(1) Our solution extends data transport to any network, not only the PSTN(2) Service control can be performed from the IP network
SSP SSP
SCP
Internet (HTTP/CGI)
Web server
PSTN
PSTNIP
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
31
Summary• Legacy systems are unlikely to disappear overnight: the future will
be hybrid
• Main contributions– Thorough assessment of the benefits in integrating Telecoms and Internet
– A service-centric and programmable architecture
– A method for determining service components
– A method for interfacing with service system elements, including existing networks and mechanisms
• We provide a unified way to interface with existing networks
• Our method enables smooth introduction of new services
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
32
Summary (cont’d)
• Future directions– Inter-provider interface
• how to make service control layers of different operators talk to one another?
– Management• how to manage the behavior of a service?
• how to allocate resources for a service and control this allocation?
• how to solve feature interactions?
– Performance• what do we need to do in order to build a system that performs as
reliably as the PSTN?
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
33
Java Service Layer
Summary (cont’d)
• Future directions– Extension to wireless networks
• what are the effects of the characteristics of wireless networks on the design of the components?
BSSSoftware Radio
Creation and Control of Hybrid Services
Institute for computer Communications and Applications
Swiss Federal Institute of Technology, LausanneCommunication Systems Division (SSC)
34
References
• J. P. Hubaux, C. Gbaguidi, S. Koppenhoefer and J. Y. Le Boudec, “The impact of the Internet on Telecommunication architectures”, Computer Networks, Feb. 1999
• C. Gbaguidi, J. P. Hubaux, G. Pacifici and A. N. Tantawi, “Integration of Internet and Telecommunications: An architecture for hybrid services”, JSAC, Sept. 1999.
• C. Gbaguidi, J. P. Hubaux, M. Hamdi and A. N. Tantawi, “A programmable architecture for the provision of hybrid services”, IEEE Comm. Mag., July 1999.
• C. Gbaguidi, S. Znaty and J. P. Hubaux, “Multimedia resources: An information model and its application to an MPEG2 video codec”, JNSM, Sept. 1998.