Rossana Andrade

1
Description of WIN Incoming Call Screening
Service usingUse Case Maps

• Rossana Andrade
• randrade_at_csi.uottawa.ca

2
Wireless Intelligent Networks

• TIA/EIA standard
• IN technology into wireless networks
• separates call processing intelligent and feature
  functionality from network switches
• facilitates mobility management functions
• offers a diversity of enhanced services to
  subscribers
• WIN Services
• Calling Name Presentation (CNAP)
• Voice Controlled Services (VCS)
• Incoming Call Screening (ICS)

3
WIN Network Reference Model
4
How WIN Is Described using UCMs
To UCM Scenario
Steps
From WIN Standard
WIN Informal Description
1
Paths and Responsibilities for the general WIN
Scenario
Paths and Responsibilities for the ICS service
Scenario
WIN Services (e.g. ICS) Informal Description
2
3
DFM Functional Entities
Components based on FE
4
NRM Network Entities
Components based on NE
Mapping of Fes to NEs
Responsibilities based on FE and NE
5
MSCs (low level of details for NEs)
Paths and Responsibilities based on NEs
6
5
Incoming Call Screening Service

• Provides for alternate routing, blocking, or
  allowing of specified incoming calls
• Incoming Call Termination Treatments
• Terminated normally to the subscriber with normal
  alerting
• Terminated normally to the subscriber with
  distinctive alerting
• Forwarded to another number
• Forwarded to voice mail
• Routed to subscriber-specific announcement
• Blocked

6
Wireless Intelligent Network Scenario using Use
Case Maps
Wireless Intelligent Network
callBlocked
ICS
incomingCall
callSetup
callForwarded
request
ReqServ
voiceMail
serviceRequest
announcement
7
ICS UCM Scenario based on NRM
SCP
HLR
voiceMailboxNumber
screeningFunction
anotherNumber
normalAlerting
checkICS
distinctiveAlerting
MSC
IP
incomingCall
voiceMail
playSpecAnnounc
checkLocation
callForwarded
playBlockAnnounc
callSetup
Routing
callBlocked
announcement
8
ICS Interaction with other Wireless Services
Wireless Intelligent Network
announcement
callForwarded
callBlocked
ICS
incomingCall
E911
SCA
PCA
voiceMail
callSetup
ReqServ
request
serviceRequest
9
Prototyping and Validation of the General Packet
Radio Service A Data Service of GSM

• Brahim Ghribi, Laurent Andriantsiferana

• Develop validated protocol suites and use cases
  for mobile systems
• Develop prototypes of these systems.
• This is done by using formal methods (LOTOS,
  SDL,...)

10
Why Develop a Formal Prototype?

• The protocols and services can be validated early
  during the standardization process.
• Ambiguities and errors can be detected and fixed
  before the implementation phase.
• Feedback and suggestions can be provided to the
  standardization committee.
• The prototype can provide a way to observe and
  simulate the behaviour of the system before the
  actual implementation.

11
Problems With Standards

• Abstraction and separation of concerns not used
• Information is spread through out the draft
  documents
• Changes may have unknown global effects
• Incomplete details and ambiguities
• Slow process
• gt A Need to address these issues by defining a
  methodology
• for Standard development

12
LOTOS

• LOTOS (Language of Temporal Ordering
  Specifications)
• A formal Specification Language for Distributed
  Systems
• gt An ISO standard
• Application Areas
• Protocols, Telephony, Distributed Systems.
• Used for
• Formal Specification, Design, Design
  Validation,
• Test Case Generation.

13
Transmission Plane
14
Validation Activities

• By using various tools such as ELUDO (LOTOS
  toolkit
• developed at the University of Ottawa) and LOLA
  (developed
• at the University of Madrid) we can
• Execute the LOTOS specification in a Step-by-Step
  mode.
• Generate a number of representative use cases,
  thus providing a set of behaviour scenarios.
• Generate finite state machines that can be used
  for verification such as model checking.
• Generate MSCs (Message Sequence Charts) to
  visually inspect the different scenarios.

15
An Example Scenario
16
Future Work

• Similar work towards
• - UMTS/IMT-2000.
• - WIN (Wireless Intelligent Network)
  Services
• Investigate the application of SDL versus LOTOS
  in prototyping Wireless Networks

This project is funded by ARRC (Advanced Radio
Data Research center) of MOTOROLA Canada. NSERC
under an IOR grant.