A SIPBased Network for Distributed Simulation

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A SIP-Based Network for Distributed Simulation
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Introductions and Background

• Gestalt LLC
• Global engagements require coordination and
  integration of multiple systems within military
  branches and between those branches - and between
  coalition forces. To ensure combat readiness of
  war fighters, armed forces must minimize
  boundaries and seamlessly share information.
  Decision-makers must be empowered with more
  robust and accessible information so they can
  train, as they would fight.
• Multi-Channel Service Oriented Architecture
  (MCSOA)
• A peer-to-peer (P2P) Service Oriented
  Architecture (SOA) facilitating distributed
  communication between systems infrastructure
  focused on integrating disparate systems across
  wide-area-networks.
• Brian ONeill, boneill_at_gestalt-llc.com
• and William Back, bback_at_gestalt-llc.com

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SIP for Simulation

• Using the Session Initiation Protocol to Create
  a Standards-Based Service Oriented Architecture
  to Support Distributed Networks for Simulation
• Agenda
• Motivation
• Solution
• Architecture

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• MOTIVATION

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Current State of Training Events

• Training events follow a fairly standard
  life-cycle
• Training audience and objectives are identified.
• Simulations are identified to meet training
  requirements.
• Scenarios are created for each simulation.
• The scenarios are coordinated and tested, often
  at a pre-exercise event.
• The training audience gathers together at a
  simulation center for the actual training event.
• After action analysis is performed for both
  technical and operational feedback.

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Problems With Current State

• Time Consuming and Expensive
• Develop a scenario for each simulation.
• Collaboration tests must occur to ensure
  enumerations match and all entities are accounted
  for.
• Must ensure interactions between simulations are
  fair and consistent regardless of the simulations
  hosting the particular entities.
• Must set up and support expensive training
  centers with hardware, software, and staff.
• The high cost of the training centers means that
  there are few of them, which limits training
  opportunities.
• Sending trainees to training centers adds
  additional cost, also reducing training
  opportunities.

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Scenario Development

• In order to support particular training objective
  it is necessary to have an environment that
  supports the execution of the training tasks.
• For military training this includes
• Terrain
• Environment
• Simulated friendly and opposing forces
• Currently these are created for each simulation
  participating in the event.
• Redundant effort
• Extended testing
• Requires a knowledgeable scenario developer for
  each system.

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Training Centers

• Provide the tools and services necessary to host
  a training event
• Hardware to run the simulation systems.
• Hardware to support exercise participants.
• High speed networks for internal and external
  connections.
• Meeting facilities to support pre-mission
  briefings and after action review.
• Support staff to
• Run the simulations.
• Provide technical support and troubleshoot
• White cell controllers.
• Role players.
• This can be convenient since everything is
  conveniently located, but it has problems
• Any one feature can limit the available training
  capability.
• Limited (expensive) training centers limits
  training opportunities

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Limited Number of Training Events

• Since simulation is limited to training centers,
  frequency of events is limited.
• For example, the DMOC hold four main events every
  year.
• Large scale events, such as UFL occur even less
  frequently.
• Problems
• Given limited resource, participants are also
  limited, meaning not everyone is getting trained.
• Training for mission rehearsal is also difficult
  because of the large lead time required to set up
  an event.
• Fewer training events means less of a likelihood
  to train lower priority tasks. For some training
  audience members this means little or no training.

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• SOLUTION

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Scenario Service

• Single scenario service available to all
  simulations for initialization.
• Expands on concepts such as the Scenario
  Generation Server and the Distributed Database
  Development (RD3)
• Benefits
• Allow any set of compliant simulation system to
  initialize from the same scenario.
• Common interface for developing scenarios - less
  training and support.
• Provide for replay and comparison across a number
  of alternative simulations.
• Desired Services
• Ability to create, copy, edit, and search
  repository.
• Ability to easily import from real-world C2
  systems.
• Metadata support for finding appropriate
  scenarios.
• Ability to support initialization of multiple
  simulation systems from the same scenario.

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The Communications Infrastructure

• Centralize the simulation service and expose its
  use to a distributed audience.
• Requirements of the communication mechanism
• Ability to communicate over the wide-area-network
  (WAN)
• Allow parties to join in an ad-hoc manner
• Provide for session creation between end-points
• Allow entities to monitor status and availability
  of resources and other entities on the network.

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Alternative Training Centers

• Separate the functionality provided by training
  center into logical parts
• Co-locate hardware and software for running
  simulations into a highly reliable environment as
  training servers, accessible to a wide number of
  training sites.
• Encourages greater use of the systems if
  generally available.
• Leverages H/W and S/W budget by not replicating
  at each center.
• Redefine training centers from locations to hold
  training to centers of excellence to support
  training.
• Train as much as possible in a realistic
  environment rather than at a sim center.

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• ARCHITECTURE

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The SIP Protocol

• What is SIP?
• SIP is a standard published by the Internet
  Engineering Task Force (IETF), RFC 3261
• It is an asynchronous messaging protocol.
• Used heavily in IP telephony, where its has been
  proven to be both reliable and suitable for
  deployment on secure networks.
• More power than HTTP, with provisional responses,
  
• What is SIMPLE?
• An extension to SIP for instant messaging and
  presence capabilities.
• Used by Windows Messenger buddy lists, IM,
  voice and video.

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SIP Capabilities / Messages

• SIP
• Register
• When entities join the system, they register
  their availability with a central server,
  heart-beating with that server.
• Invite
• Two entities can invite each other to join a
  real-time direct P2P session over which any media
  can be transferred. (e.g. HLA, VoIP)
• SIMPLE
• Messaging
• Entities can message one-another, that payload of
  which could be service invocations (e.g. SOAP).
• Presence
• Includes a lightweight, publish and subscribe
  mechanism to gather the status and availability
  information of an entity on the network.

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The Transition

• Distributed Systems communicate in much the same
  way people do and can therefore leverage the same
  infrastructure and protocols.
• In this case, a conference-call is a simulation
  with multiple participants connected to the same
  session, playing out a common scenario.
• Systems such as the Scenario Generation Server
  (SGS) are moderators in the discussion, and could
  control the signalling required to initialize the
  conference.
• Migration path could be HLA-based sessions, where
  SIP is used to coordinate bus initialization
  across the WAN.

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The Benefits of SIP

• Built to support ad-hoc sessions between remote
  endpoints.
• Support for mobile/portable devices and is
  already deployed on cell-phones and PDAs, which
  extends your possible participant base.
• Simulation can piggy-back on the IT acceptance of
  SIP for VoIP communication.
• Commercial Off-the-shelf support in IT and
  applications. (e.g. commercial SIP stacks, border
  controllers, and application servers)
• Leverages all the concepts of HTTP
• There is a smaller learning curve for application
  developers.
• Re-use infrastructure laid out for Web Services

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Components

• SIP Server
• Functions as a Registrar, Presence and Messaging
  server for the systems involved in the simulation
• Session Border Controller
• Functions as a secured media-gateway for the
  session between the systems.
• Discovery Mechanism
• Functions as a yellow-pages of available
  services.

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The Architecture
AwSim
Training Center
SUBSCRIBE sgs_at_tc1
NOTIFY sgs_at_tc1
SGS
INVITE sgs_at_tc1
tc1
VoIP
INVITE sgs_at_tc2
SUBSCRIBE cbs_at_tc2 NOTIFY cbs_at_tc2
tc3
Core Battle Systems (CBS)
Simulation Session (e.g. HLA)
Discovery
tc2
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Summary

• SIP can be used for a standards-based
  infrastructure for distributed communication
  providing the required functionality required the
  modeling and simulation community for remote
  training and system inter-system communication.
• Further research
• Exact interaction models
• Migration Path for existing systems
• Exploration of the new functionality available
  once the simulation systems can incorporate many
  distributed systems and participants attached
  over smaller, more mobile devices.

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Thank You.
Brian ONeill Technical Architect, Gestalt
LLC Multi-Channel Service Oriented
Architecture Mobile [phone] boneill_at_gestalt-
llc.com,