XGSP Session Protocol DS-RT 2005 Grid Tutorial

IEEE DS-RT 2005 Montreal Canada Oct. 9 2005

Geoffrey Fox

CTO Anabas Corporation andComputer Science, Informatics, Physics

Pervasive Technology LaboratoriesIndiana University Bloomington IN 47401

gcf@indiana.eduhttp://www.infomall.org

Collaboration Web services System

Event Messaging Service

(NaradaBrokering)

XGSP Conference Control Service

Audio Video

Web Service

Instant Messaging

Web Service

Shared Display

Web Service

Shared

….

Web Service

XGSP Framework To integrate heterogeneous systems into one

collaboration system, we need to reach the following goals:

(1) Different kinds of application endpoints should join leave in the same collaboration session.

(2) Different providers for multipoint A/V and data collaboration should be connected together to build unified A/V and data multipoint channels.

(3) A common user interface should be present for all the collaboration participants using different A/V and data application endpoints.

XML based General Session ProtocolServices

The XGSP conference control includes three services: conference management supports user sign-in, user

create/terminate/join/leave/invite-into XGSP conferences

application session management provides users with the service for creating/terminating

application sessionsXGSP application session management provides the services to A/V and data application endpoints and communities, controlling multipoint A/V RTP and data channels.

floor control manages the access to shared collaboration resources in

different application sessions.

XGSP Conference Control Architecture

Conference Manager

NaradaBrokering

User 5

User 3User 2

NodeManager

ApplicationInstance 0

ApplicationInstance 1

User 1

App Sessions

ConferenceCalendar

ApplicationRegistry

UserAccounts

XGSP Conference Management Provides services of Create / Modify / Terminate

Conference, allowing users to make meeting schedules and look up active meetings

Conference Calendar Users in a XGSP Conference

• three roles: administrator, conference chairman and normal users.

XGSP Conference membership maintenance

XGSP Application Session Management Different Application sessions in XGSP

• public application sessions and private application session Topic name schema for application sessions

• /xgsp/conferenceID/Application-Session-ID

• public application sessions ~ < application type, sequence number >

• private application sessions ~ < application type, initiator-ID, sequence number>

for example: /xgsp/ourtestroom/whiteboard/testuser/0123 Creating and terminating application sessions Join/Leave Application Session

XGSP Floor Control XGSP should provide:

• Floor control primitives, including: request floor, release floor, grant floor, cancel floor, remove floor request

• mediator-controlled floor control: to support the mediator control policy

• Collaboration applications have to define their own roles in the XGSP registration so that the mediator could assign the role of the application to each user.

for example, a shared PowerPoint application should define master/non-master role.

XGSP Example: Conference Schedule

< XGSPConference><ConferenceID> GameRoom </ConferenceID><ConferenceName> Our Chess Game </ConferenceName><ConferenceCreator> John </ConferenceCreator><ConferenceDate>

<StartTime> 9:00AM </StartTime> <EndTime> 12:00AM </EndTime></ConferenceDate><ConferenceType> Moderated </ConferenceType><ApplicationList>

<ApplicationID> Audio-Video </ApplicationID><ApplicationID> chat </ApplicationID><ApplicationID> chess </ApplicationID>

</ApplicationList></XGSPConference>

XGSP Example: application role definition

< ApplicationRegistry>< ApplicationID> chess </ApplicationID><roles>

<role> <roleName> black </roleName> <capabilities> player-first </capabilities> <roleName> white </roleName> <capabilities> player-second </capabilities> <roleName> observer </roleName> <capabilities> non-player </capabilities> </role> </roles>

…. </ApplicationRegistry>

XGSP Example: New Session <CreateAppSession>

<ConferenceID> GameRoom </ConferenceID><ApplicationID> chess </ApplicationID><AppSessionID> chess-0 </AppSessionID><AppSession-Creator> John </AppSession-Creator><Private> false </Private>

</CreateAppSession><SetAppRole>

<AppSessionID> chess-0 </AppSessionID><UserID> Bob </UserID><RoleDescription> black </RoleDescription>

</SetAppRole><SetAppRole>

<AppSessionID> chess-0 </AppSessionID><UserID> Jack </UserID><RoleDescription> white </RoleDescription>

</SetAppRole>

XGSP Audio-Video Session Management XGSP signaling protocol for

• H.323 signaling protocols (H.225, H.245) • SIP signaling protocol ( Invite, Bye Message )• Access Grid ( Unicast VIC & RAT )

Join XGSP Session, Leave XGSP Session,

Invite into XGSP Session, Expel from XGSP Session Activate the XGSP session

• the XGSP session server will link all the “rooms” in the session together by connecting multipoint A/V and data channels from different communities to the XGSP A/V Media and Data Channel Services.

Link/Disconnect XGSP SubSession

XGSP Audio-Video Session Control Service

creating/destroying sessions allowing endpoints to join/leave session

• Common signaling protocol• Translate H.323/SIP into it XGSP

make audiovisual selection• Video/audio stream subscription• Stream filters generation

managing audiovisual service elements • Video/audio mixing, transcoding service management• Service meta-data description• Search service through NaradaBroker

XGSP AV Signaling Protocol with H.323H323 Terminal H323 Gateway

H225.Setup

H225.Connect

JoinAVSession

JoinAVSession OK

Terminal CapabilitySet

ACK

Terminal Capability Set

ACK

OpenLogicChannel ( Video )

ACK

JoinAVSession (Video)ACK

OpenLogicChannel ( Video )

OpenLogicChannel ( Audio )

ACK

OpenLogicChannel ( Audio )

ACK JoinAVSession (Audio)

ACK with video RTPLink<IP Addr, Port>

ACK with Audio RTPLink<IP Addr, Port>

with the RTPLinks <IP Addr, Port>

& capability description

H.225Call Setup

H.245CapabilityExchange

OpenAudio &VideoLogicChannels

XGSP H323Session server

Steps to build Collaboration Web-Services using XGSP and NaradaBrokering

Use NaradaBrokering for control communication and data distribution

Define roles and its capability in XGSP Define application specific processing services and

hooked it into NaradaBrokering Implement the interface between the XGSP

NodeManager and application clients

XGSP Futures XGSP needs richer set of capabilities to capture

different floor models and to allow multiple applications to be supported• Straightforward but time consuming• Use Grid metadata catalog to automatically store

Grid/Web service security model – still maturing in other applications

Need to support rich set of group security models