200 likes | 413 Views
Dynamic Spectrum Access Policy. Lynn Grande COT6930 – Semantic Web Fall 2011. What is Dynamic Spectrum Access?. The real-time adjustment of spectrum utilization in response to changing circumstances and objectives.
E N D
Dynamic Spectrum Access Policy Lynn Grande COT6930 – Semantic Web Fall 2011
What is Dynamic Spectrum Access? The real-time adjustment of spectrum utilization in response to changing circumstances and objectives. NOTE―Changing circumstances and objectives include (and are not limited to) energy-conservation, changes of the radio’s state (operational mode, battery life, location, etc.), interference-avoidance (either suffered or inflicted), changes in environmental/external constraints (spectrum, propagation, operational policies, etc.), spectrum-usage efficiency targets, quality of service (QoS), graceful degradation guidelines, and maximization of radio lifetime. **From IEEE P1900.1-2008
What is Policy? a) A set of rules governing the behavior of a system. NOTE 1―Policies may originate from regulators, manufacturers, developers, network and system operators, and system users. A policy may define, for example, allowed frequency bands, waveforms, power levels, and secondary user protocols. B) A machine interpretable instantiation of policy as defined in (a) NOTE 2―Policies are normally applied post manufacturing of the radio as a configuration to a specific service application. NOTE 3—Definition b) recognizes that in some contexts the term “policy” is assumed to refer to machineunderstandable policies. **From IEEE P1900.1-2008
What is Cognitive Radio? a) A type of radio in which communication systems are aware of their environment and internal state andcan make decisions about their radio operating behavior based on that information and predefined objectives. NOTE—The environmental information may or may not include location information related to communication systems. b) Cognitive radio [as defined in item a)] that uses software-defined radio, adaptive radio, and other technologies to adjust automatically its behavior or operations to achieve desired objectives.
What is Whitespace? Whitespace (unused unlicensed spectrum)
Relationship between cognitive radio, dynamic spectrum access and policy. From: IEEE DYNAMIC SPECTRUM ACCESS POLICY STANDARDS WORK Lynn Grande, MILCOM 2009.
Abstract Abstract: Cognitive and next generation radio technology is instrumental in handling the dynamic nature of spectrum management. Efficient use of spectrum is essential because there is more competition for licensed and unlicensed spectrum and it is being divided up to more stakeholders. There are two distinct changes in the area of spectrum management. The first is the availability of white space (broadcast) spectrum bands that was freed up by the conversion to digital TV. The second is the United States government broadband plan, which involves selling off some of its licensed spectrum for profit. This greatly affects the military, which now has a much smaller piece of the spectrum pie. How can Semantic Web technology improve this? We need an ontology that can define radio characteristics and define a policy ontology framework to manage the dynamics changes in a radio system. If there was a common ontology, all the devices involved in a radio system and between radio system would be able to share information easier.
Abstract, continued We also need these ontologies to be able to search the spectrum databases for available white space spectrum. These databases will be accessed over the internet. There are many stakeholders affected by the spectrum changes, such as 1) commercial wireless and networking product suppliers: they need to know how to search for available spectrum to use in their local devices; 2) military: need to efficiently use their smaller spectrum band; 3) Federal Communications Commission: they need to be able to propagate spectrum changes easily to consumers and make sure that users and suppliers are following the rules; 4) public safety domain: they need an easier way to taker over spectrum in emergencies; and lastly, 5) the general public: who wants all their wireless devices to work all the time.
Abstract, continued I do not propose to solve all these issues but to apply the knowledge and tools defined in this course to create a starting point that can be carried on in my IEEE working group (P1900.5) for completion and publication in a standard that could be accepted by the stakeholders mentioned. The demonstration of this project will involve creating a subset policy ontology and a way to query the white space database service for available spectrum. Some of the devices needing spectrum could be personal area networking devices for medical purposes.
Work Outline • Create Policy Ontology subset of Kaoswith Protege; • Tie in existing radio ontology create by Wireless Innovation Forum MLM working group. • Create white space database interface; • Create queries to white space database; • Demonstrate receiving results of available white space and having that information disseminate to devices using policy • Document results.
Use Cases • Actors • White Space database service • Radio-enabled network device (CR) • Policy Manager • Reasoner • Software Control • Policy Enforcer
Use Cases, continued • White Space DB Service Access Use case Diagram
Use Cases, continued • Cognitive Radio Use Case Diagram
Design White Space devices, be they access points or clients, will operate in TV-broadcast spectrum that isn't being used locally. When a White Space device is switched on it connects, over the internet, to a chosen database and supplies its location. The database responds with a list of radio frequencies that are available locally. The Policy Manager selects one (or more) to use, and passes that information on to the CR. The CR then uses that frequency to communicate on a particular channel.
Draft Policy Ontology • Use requirements from P1900.5 standard - IEEE Standard Policy Language Requirements and System Architectures for Dynamic Spectrum Access Systems • Some of the entities: • Policy Set • Policy Rule • Policy Effectivity • Time • Location • Policy Action • Use subset of Kaos policy ontology
Kaos Policy ontology The Kaos policy Ontology was created under DARPA/NASA sponsorship. The current version of KAoS Policy Ontologies(http://ontology.coginst.uwf.edu/) defines basic ontologiesfor actions, actors, groups, places, various entities related to actions (e.g., computing resources),and policies. I have loaded this into Protégé as shown.
White Space Database Service Use API definition from actual white space database service at Spectrum Bridge; After the access point registers with the white space database, the list of available frequencies are returned for use in the CR devices.
Implementation & Test • Created ontologies in Protégé; • Created Java code to: • Use Jena for ontologies. • Create test code to simulate: • Querying white space database for available spectrum; • Policy creation sent to CR using policy ontology. • Results will be documented in final paper.