Applying Design Patterns to Wireless Sensor Network Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

References [1]S.O. Amin and C.S. Hong, “On Design Patterns for Sensor Networks,” The 27TH KIPS Spring Conference, [2]K. Tei, Y. Fukazawa, and S. Honiden, “Applying design patterns to wireless sensor network programming,” Computer Communications and Networks, ICCCN Proceedings of 16th International Conference on, 2007, pp. 1099–1104. Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

sensor representation ‘Object’ of OOP sensing the environment and responding it ‘methods’ of an object Sensor states ‘attributes’ of an OOP object Modeling sensors as an OOP objects Enhancement in the management of sensor networks good sensor network design Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall 2010 Apply Design Patterns of other Domains in Sensor Networks 3

Design patterns for Sensor Networks: Mediator Façade Chain of responsibility Watchdog Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall 2010 Apply Design Patterns of other Domains in Sensor Networks 4

Mediator in WSN Intent Encapsulates objects interactions Promotes loose coupling Lets you vary their interaction independently Decouples many peers Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Mediator in WSN Motivation Multi agent system Agent decomposition to enhance reusability Distribution of behavior results in many interconnections Solution is encapsulating collective behavior in a separate mediator module Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Mediator in WSN Motivation (example) in smart ubiquitous environment, mediator contains the control logic adding a new smart appliance requires only modification of the mediator decouples all the appliances within the system from each other Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Mediator in WSN Structure Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Mediator in WSN Applicability When a set of modules communicate in well-defined but complex ways When it is difficult to reuse a module because it refers to and communicates with many other modules. Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Mediator in WSN Consequences vary and reuse Colleague and Mediator independently Simplifies the maintenance of the system New functionality can be added at mediator without affecting colleagues Simplifies the communication protocol Mediator can become overly complex Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Few more Patterns at a glance Façade makes subsystem easier to use Provides simplified view to its users For example in smart ubiquitous environment, as soon as house owner puts his keychain on Smart key stand many related work such as turning on the lights, switching on the answering machine and so on, can be started as a sub layer. Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Chain of responsibility User wants to detect some activity If one sensor has not detected any action, it can ask the next sensor Each sensor that detect the activity, it can respond a vehicle may contain multiple sensors that can accomplish a given task Provides a way for the sensor to be selectable Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall 2010 Few more Patterns at a glance 12

K. Tei, Y. Fukazawa, and S. Honiden, “Applying design patterns to wireless sensor network programming,” Computer Communications and Networks, ICCCN Proceedings of 16th International Conference on, 2007, pp. 1099–1104. Applying Design Patterns to Wireless Sensor Network Programming Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Applying Design Patterns to Wireless Sensor Network Programming Middleware for WSN abstracts a network as an entity and hides programming difficulties from programmers. Step 1:discuss major middleware languages and compare the capabilities of their primitives. Step 2:extract design patterns from the representative middlewares to cover the missing capabilities identified in the comparison. Step 3:Apply this extract design patterns. Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Applying Design Patterns to Wireless Sensor Network Programming Various middlewares have been proposed by reseachers in the WSN community. Each middleware has different advantages and disadvantages in terms of : energy efficiency robustness number of tasks which a sensor node can hold simultaneously. Due to the diversity, a WSN administrator can select a middleware best suited for his or her the WSN. Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Applying Design Patterns to Wireless Sensor Network Programming MIDDLEWARES FOR WSN TinyDB EnviroTrack Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Applying Design Patterns to Wireless Sensor Network Programming The three kinds of tasks are : 1.Nest 2.Offline Delivery 3.Tracking Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Applying Design Patterns to Wireless Sensor Network Programming Type of Pattern: In-network Result Sharing Pattern Out-network Result Sharing Pattern In-network Data Repository Pattern In-network Tracking Pattern 18 Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall 2010 Nest Task Offline Delivery Task Tracking Task In-network Result Sharing Pattern

Applying Design Patterns to Wireless Sensor Network Programming Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall 2010 Extracting Design Patterns A pattern consists of the six essential elements: 19

In-network Result Sharing Pattern Design Patterns for Nest name it the In-network Result Sharing Pattern. Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

In-network Result Sharing Pattern Tasks can share their results through the in-network data repository The sub-tasks store their results in the data repository The main task loads the results from it to execute its own task This pattern uses an in-network data repository, which is maintained at each sensor node Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

In-network Result Sharing Pattern Sequence of the In-network Result Sharing Pattern Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

In-network Result Sharing Pattern Related pattern The In-network Result Sharing Pattern is strongly related to the In- network Data Repository Pattern A variation of the In-network Result Sharing Pattern can be conceived, i.e., the Out-network Result Sharing Pattern. Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Applying Design Patterns Applying the In-network Result Sharing Pattern Consider the case that a main task uses a result of a sub-task. The sub-task is described as follows. Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Applying Design Patterns Informally, the main task is described as follows. Modify the sub-task to store its result in a buffer as follows. Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall

Applying Design Patterns Modify the main task to retrieve a result of the sub-task from the buffer, as follows. The main task is formal, and can use the result of the sub-task. With this conversion, Nest can be described in TinyDB. Sajjad Soroush AmirKabir University of Technology, Department of Computer Engineering & Information Technology Advanced design pattern Course Fall