TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY
An Implementation of the Server Cache Synchronization
Protocol (SCSP)Jose Costa Requena
Raimo Kantola [email protected]
SPIE Conference Boston, September 1999
TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY
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TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY Contents
Problem Definition
Conclusions and Future Work
SCSP as Solution Protocol Specifications (RFC 2334)Basic Features
Our Implementation Modules in the implementationInteraction between modules
ApplicationsGLP ImplementationGLP Interoperability : IP GSTN
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TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY Problem DefinitionTEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY
Directories are key component for IP based communications networks.
Subscriber & User
Database
NetworkOperator
ServiceProvider
Value AddedService Provider
Billing
UsageUsage
Billing User Data Management
Subscription & Service Profile Management
Usage
The large amount of data is stored in distributed databases the changes must be updated among the entities related to the same service.
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TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY Problem DefinitionTEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY
IP TelephonySignaling server
IP TelephonySignaling server
Zone B
Zone A
Zone B Database
Zone A Database
Directories hold static and dynamic information about the users and the services themselves.
Services need to interoperate across administrative boundaries anddirectories need to be accessible from everywhere.
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TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY Our SolutionTEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY
The SCSP solves the problem of data replication/synchronisationin a group of distributed servers without heavy overheads like in the actual tight consistency techniques.
SCSPSCSP
IP TelephonySignaling server
IP TelephonySignaling server
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TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY
Server Group (SG). Is the group of servers to be synchronised.
Local Server (LS). Is the server under scrutiny.
Direct Connected Server (DCS). Is the server directly connected to LS.
TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY SCSP Specifications
The SCSP elements
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TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY SCSP Specifications
The SCSP is based on three sub-protocols.
Hello Protocol is used to know whether the connection between servers is available.
Cache Alignment Protocol allows a server to synchronise its entire data:
exchanging short summaries from the entire database, comparing of
summaries to know the newest data, requesting the entire information to
the server which provided the summary with the newest data
Cache State Update performs a flooding mechanism where any
new information in one of the servers is dynamically updated in
all other servers.
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TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY
SCSP Algorithms module Communications module (TCP/IP)User Interface Auto Configuration SystemDatabases module Object Tables
UserInterface
SCSP
TCP/IP
SCSP
TCP/IP
DATA BASESDATA BASESDATA BASESDATA BASES
Auto ConfigSystem
Auto Config.System
OBJECT TABLES
OBJECT TABLES
UserInterface
SCSP Modules
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TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY Modules Interaction
t
HFSM
CAFSM
CSU
SCSPSCSP
HFSM
CAFSM
CSU
SCSPSCSP
Server i Server i+1Hello Packets
Cache Alignment packets
Cache State Updatepackets
CLIENT USE SCSP
PRIMITIVES
CLIENT USE SCSP
PRIMITIVES
tt
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TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY Applications
SCSP for data replication in the GLP Implementation
SCSP
database
GLPGLP
database
SCSP
SCSP
database
GLP
LSLS
LSLS
LSLS
GLP: Gateway Location ProtocolLS: Location ServerITAD: Internet Telephony Administrative Domain
ITAD 1
ITAD 3
ITAD 2
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TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY
GATEKEEPER
SS7 PSTN
GLPDatabase
SCSP
TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY Applications
SCSP as the common element for a global GLP Implementation and interoperability between GSTN and IP
GATEKEEPERGLP
DatabaseSCSP
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GATEKEEPERSCP
SS7 PSTN or GSM
TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY Applications
SCSP as basic component to allow interoperability between INdatabases and user information directories in IP
GATEKEEPER
GLPDatabaseSCSP
DatabasesSCSP
GLPDatabaseSCSP
IP
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TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY
TEKNILLINEN KORKEAKOULUHELSINKI UNIVERSITY OF TECHNOLOGY Conclusions
SCSP has been developed in a modular way to provide a generic service to be used by other systems for their data replication.
SCSP follows a building-block design to permit its integration with other mechanisms to achieve an efficient overall behaviour.
In terms of overall positioning we consider the SCSP as a key tool for the future services globalisation.
NOWADAYS ...NOWADAYS ...
We continue working on future applications of the
SCSP as the generic component to allow
interoperability between IN and IP services.
SCSP could become a key component of the emerging
directory enabled networks.
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