Overview Of Tenet: Architecture For Tiered Sensor

A.Jeevarathinam et al. / International Journal of Engineering Science and Technology (IJEST)

Overview Of Tenet: Architecture For Tiered Sensor Networks A.JEEVARATHINAM Lecturer, Computer Science Dept, Karpagam University, Pollachi Main Road, Eachanari Post, Coimbatore – 641 021, Tamil Nadu, India

K .LAKSHMI Lecturer, Computer Science Dept, Karpagam University, Pollachi Main Road, Eachanari Post, Coimbatore – 641 021, Tamil Nadu, India

K. THILAGAM Research Scholar, Computer Science Dept, Karpagam University, Pollachi Main Road, Eachanari Post, Coimbatore – 641 021, Tamil Nadu, India

K. RAMA Lecturer, Computer Science Dept, Karpagam University, Pollachi Main Road, Eachanari Post, Coimbatore – 641 021, Tamil Nadu, India

MANJU PRIYA .S Research Scholar, Computer Science Dept, Karpagam University, Pollachi Main Road, Eachanari Post, Coimbatore – 641 021, Tamil Nadu, India Abstract Most sensor network research and software design has been guided by an architectural principle that permits multi-node data fusion on small-form-factor, resource-poor nodes, or motes. We argue that this principle leads to fragile and unmanageable systems and explore an alternative. The Tenet architecture is motivated by the observation that future large-scale sensor network deployments will be tiered, consisting of motes in the lower tier and masters, relatively unconstrained 32-bit platform nodes, in the upper tier. Masters provide increased network capacity. Tenet constrains multimode fusion to the master tier while allowing motes to process locallygenerated sensor data. This simplifies application development and allows mote-tier software to be reused. Applications running on masters task motes by composing task descriptions from a novel tasklet library. Our Tenet implementation also contains a robust and scalable networking subsystem for disseminating tasks and reliably delivering responses. We show that a Tenet pursuit-evasion application exhibits performance comparable to a mote-native implementation while being considerably more compact. Keywords: Sensor Networks, Network Architecture, Motes, Tiered Networks 1 INTRODUCTION The wireless sensor network (WSN) technology is a key component for ubiquitous computing. A WSN consists of a large number of sensor nodes. Each sensor node senses environmental conditions such as temperature, pressure and light and sends the sensed data to a base station (BS), which is a long way off in general. Since the sensor nodes are powered by limited power batteries, in order to prolong the life time of the network, low energy consumption is important for sensor nodes. Wireless sensor networks are distributed computing systems that have many limitations. These include limited computing power, low memory, typically can run on batteries, and have low bandwidth available for communication. A typical application for a sensor network (see Figure 1) could be a deployment of sensors to observe a physical area and report of any intruders entering the protected zone. The “x” marks a location where the sensor with the circle around it has detected an intruder of some kind. This information must be delivered to a base station of some sort in a timely fashion.

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In this paper, we report on the design of a generic sensing software called TENET. TENET is designed for a two-tier network of sensors and actuators: a lower tier consisting of low-power sensing nodes which we generically call motes and which enable _exible deployment of dense instrumentation, and an upper tier containing fewer, relatively less constrained, 32-bit nodes with higher-bandwidth radios, which we call masters. In TENET, applications run on one or more master nodes. They task motes to sense and locally process data. Conceptually, a task is a small program written in a constrained language. The results of tasks are delivered by the TENET system to the application program. This program can then fuse the returned results, and re-task the motes or trigger other sensing modalities. More than one application can run concurrently on a TENET. We have designed and implemented TENET and have implemented several applications on it . 2.RELATED WORK 2.1 Purpose of this document This paper explains the purpose and characteristics of the TENeT (Trusted Environment with Networking eTRON) specification that provide Java APIs and message formats among smartcards and application programs for authority value （electronic voucher）transaction.This specification is one of the ‘eTRON appliance’ specifications for authority value circulation in the mobile environment. 2.2 Our Approach The Tenet software system includes all necessities for basic wireless sensor network programming: drivers, routing protocol, flow control, end-to-end reliability, a two-tier network hierarchy, and a simple scripting language for easy programming of applications. These properties, in addition to Tenet’s flexibility towards future improvements, make Tenet the ideal choice for our deployment. We have added new software pieces to Tenet for using Cyclops camera and MDA300 sensor board, implemented basic image compression, and formed a complete end-to-end system. The nest boxes are generally sparse, being spread 50 to 100 meters apart in areas of dense trees and foliage. Newer 2.4 GHz radios tend to perform poorly in these environments; instead we used Mica2s with 433 MHz radios as our wireless communication hardware in the mote-tier. This drastically limits available bandwidth but propagates farther through the foliages. These factors together enabled us to reach our goal of increasing the temporal resolution of data, providing near real time monitoring which saved time and labor for the biologist, and allowing a larger spatial area to be covered with sensors.

2. 3 TENeT Outline The advancement of authority value trading technology and the spread of networks as social bases in recent years has led the continued offering of services that electronically issue and use authority values, such as money and tickets. Though the types of electronic authority values being handled today are limited, it is projected in the future that, as authority value circulation services infiltrate modern society, individual information, such as personal identity certificates, will become widely distributed and a transaction market for authority values between users, such as through auctions, will appear.

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a) Figure 1 provides an image of the TENeT-based authority value transaction environment

b) Figure 2 vibration Sensing with Onset-Detector The infiltration of authority value circulation services, however, will be accompanied by risks of a proliferation of illegal acts such as altering or forging authority values Technology protecting authority values from illegal operation will be required for the development of authority value circulation framework. Besides protecting authority values, it will also be important to assure that transactions can be done fairly, for users to securely circulate and trade authority values. In other words, when authority values are bought and sold among users for example, such illegal behavior as absconding with the authority values must be prevented. Particularly in wireless environments, such as with cell-phones, assuring transaction fairness will be an extremely important element, given that interruptions can occur in mid-transaction, due to such incidents as network cut-offs and cell-phone charge depletion. TENeT provides means to assume transaction fairness and thus enabling users to trade authority values without risks of illegal behaviors such as absconding. 2.3 Tenet Principle Multinode data fusion and multinode data processing should all be done at the master nodes Tenet" comes from the Latin word, "tenere", meaning "to hold." It refers to any opinion, principle, belief or doctrine that is held to be true by a person or group. It is generally used in connection with religion, politics and philosophy.  Fundamental Principle In a belief system or political or philosophical theory, a tenet is a principle that is accepted as authoritative. It is one of the principles on which a belief or theory is based. For example, one of the tenets of existentialist philosophy according to Jean-Paul Sartre is, "Man is nothing else but what he makes of himself."  Religion In religion, a tenet can be a central belief or doctrine that is proclaimed to be true without scientific proof. For instance, one of the tenets of Christianity is that Jesus was born of a virgin mother, while a main tenet of Hinduism is that one's present birth is the consequence of one's past actions in previous lives.  Core Value In a political system or government, or even a company or organization, a tenet is a core value. For example, freedom of speech is a tenet of American democracy, while the promise of top-quality customer service is a tenet of many businesses.  Personal Tenets An individual may possess his or her own tenets, such as always looking on the bright side of things or never being late for appointments.

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Usage in Sports The word "tenet" is also used in the sports world. "Keep your eye on the ball" and "always go for the sure out" are baseball tenets, while "keep your head up" and "hit the open man" are used in basketball 2. 5 Prescribed scope of the TENeT specifications Each of the following TENeT specifications has been prescribed to enable the mutual operability of the IC cards [M1]and application programs that make authority value transactions possible.  TENeT authority value transaction API specification An API for managing and circulating IC card authority values from application programs  TENeT messaging API specification An API for sending and receiving e2TP messages from application programs  e2TP (Extended eTRON Transfer Protocol) message specification Message format for e2TP messages and mapping method for the ISO7816-4 ADPU  TENeT message specification Message set for e2TP messages that must be provided by the TENeT specification IC card. 3. TENeT Usage Scenarios 3.1 Usage Scenarios A mobile environment is defined as “an environment where each user equips its own mobile terminal that is capable of network connection.” A typical example of the mobile terminal is a cell-phone. Authority value circulation in the mobile environment offers the following characteristics compared with authority value circulation where only a tamper proof device such as an IC card is carried.  The use of portable terminal network functions makes possible authority value interchanges with other users  The use of a portable terminal user interface makes it possible to control the authority values within an owned tamper-proof device. The usage scenarios indicated in Table 1 are conceivable through an authority value circulation in a mobile environment thanks to the above characteristics. Table 1 Usage scenarios of authority value circulation in a mobile environment

Usage scenario

Details

Purchase of authority values

Commuter passes or tickets purchased at specific locations, such as ticket vending machines at ticket gates, and charges for electronic money can be made anytime, anywhere using the portable terminal network function..

Transfer of authority values

It transfers authority values to other users. Though specialized equipment, PCs connected to networks, and the like were required for transfers in the past, authority values can be transferred through the use of portable terminal network functions, without the need for other equipment.

Exchange of authority values

It exchanges the authority value with other users. It can mutually transfer authority values using the network function of the portable terminals, the same as indicated above. Transaction services as a whole can be applied, provided that the exchange can be executed securely. Unrestricted transaction services are possible, through free markets on networks, for example.

Use of authority values

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Authority values can be used at ticket examination points and gates, by holding them overa portable terminal, in the same manner as conventional proximity type non-contact IC cards. The local communication function of portable terminals could, for example, be used in much the same way as the smart keys of automobiles to open doors automatically using authority values.

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3.2 TENeT Characteristics To enable the secure usage of authority values within various environments and in the mobile environment in particular, TENeT stores the authority values in tamper-proof devices, such as IC cards and USIMs. These are called TENeT IC cards. TENeT has adopted the “Optimistic Exchange Protocol for Fair Authority Value Transactions”[THIF01] technology to make possible the secure and fair circulation and transaction of authority values thorough networks. As a result, it possible to transact authority values, both securely and fairly, between IC cards located at a distance from each other, without inviting a concentrated on the server. To facilitate the use of the above described exchange protocol type distributed processing between IC cards from application programs, TENeT has put together a mechanism for sending and receiving messages by dispersed type transmission between IC cards and between IC cards and application programs. 3.3 TENeT Architecture System Architecture The Tenet software collects images and environmental data from every sensor node and stores them on the local server at James Reserve. Tenet applications run on the local server, and multiple Stargates act as Tenet-masters which relay commands to and data from the Cyclops nodes. A backend server at CENS retrieves the data from the local server via Internet, and archives and processes the data. These components together give a complete, real-time, end-to-end system. Figure 3 shows the various components comprising TENeT. Here following, we will we outline each of these components. Figure 3 TENeT Architecture

3..4 Tenet Advantages Tenet is a software package for flexibly programming a tiered network of sensors. The Tenet system consists of motes and less-constrained 32-bit platforms called masters. All applications run on the masters and task motes using a generic tasking API that allows the user to run simple programs on the master nodes to configure, control, sample, and process data without having to reprogram the motes. Tenet constructs seamless multi-hop routing over a tiered network of motes and masters which enables flexible deployment of sensors over large area. Tenet also provides end-to-end reliable delivery of packets with built in congestion control capability. Reliable delivery is an application requirement for our system, otherwise image quality can be severely compromised. It also allows our system to use loss-intolerant image compression techniques to increase effective network capacity since these techniques require 100% packet delivery for correct decompression. Congestion control allows our application to adapt its image transfer rate to network scale and wireless environment. By using Tenet, we can reuse all of the above networking and sensor data extraction code, thereby significantly reducing application development time.

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4 TENeT IC Card IC cards play the role of storing and managing the authority values for TENeT. Users can use the TENeT IC card for such operations as transacting, creating and deleting authority values. TENeT IC cards have multiple ‘folders’ and the authority values created or received through transactions can be stored in any folder. TENeT IC cards also have a user authentication function that prevents accessing for improperly manipulating authority values. 4.1 Functions Of TENeT Authentication function • IC card authentication - It authenticates that the user is an IC card owner. • Folder/ file access control - It sets the access privileges for folders and files. Authority value management functions • Folder creation and deletion - Creates or deletes folders within a card or • Folder list acquisition - Acquires a list of folder information within a card • Authority value creation - Creates authority values in the specified folder within a card • Authority value deletion - Deletes the specified authority values within a card • Acquisition of list of authority values (stored in the folder) - Acquires all the authority value information located in a folder within a card. Authority value circulation functions • Transfer and exchange of authority values - Transfers the specified authority values within a card or exchanges them with other authority values • Release of interrupted transactions - When the above exchange and transfer processing has been interrupted, it releases the transactions and finishes their processing. Operating system functions • Backup and restoration of the content of an IC card - Externally backs up all the information within the card, such as when the folder size has been changed 4. 2 Tasks and Task Library In the TENET task library, tasks are composed of tasklets. Each tasklet may be thought of as a service to be carried out as part of the task. The tasklets in the TENET task library provide the building blocks for a wide array of data acquisition, processing, measurement, classification, diagnostic, and management tasks. For example, to construct a task that samples a particular ADC channel 0 every 1000 ms and transmit ten samples at a time, with the tag TEMPERATURE, to its master, we write: Sample (500ms, 10, REPEAT, 1, ADC0, TEMPERATURE) -> SendPtr() This provides the most basic sampling and transmission support one might expect from a mote. It periodically collects a single sensor value and delivers data using multi-hop transport. If the application programmer wishes to put a timestamp on every packet, and send the packet only if the the sample value is above 45, then the task description will be in the following form: Mote Task Language Sample(10000ms, 1, REPEAT,ADC_LIGHT, X) -> LEQ(Y, X, 39) -> DeleteActiveTaskIf(Y) -> LocalTime(Z) -> Send() A More Complex Task Sample(1000ms, 10, REPEAT,ADC0, A) -> MeanDev(B, A) -> SetLeds(A) -> CountGEQ(C, A, 45) -> GEQ(C, C, 3) ->

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DeleteAttributeIf(C, A) -> DeleteAttribute(C) -> GlobalTime(D) -> Count(C,0, 1) -> Send() These linear forms of task construction are flexible, general, high-level, and efficient enough to support easy programming and tasking from masters. How can a TENET application make use of this tasking library? Shown below is the code for a complete application which collects vibration data from three axes at sampling frequency of 20Hz. This application is exactly what we have used for our bridge deployment. Here, SampleMDA400 is the tasklet that controls a specific vibration sensorboard, and SendStr() invokes our stream transport. Program In Master int main() { task_string = "Sample(5000ms, 1, REPEAT,2, VOLTAGE) -> /* task description */ NextHop(3)-> GlobalTime(4)-> Send()"; /* construct a task packet */ task_packet=construct_task(task_string); /* send the task */ task_id = send_task(task_packet); while (1) { (response, mode_id) = read_response(); voltage = response_find(2, response); nexthop = response_find(3, response); globaltime = response_find(4,response); store_data_to_file(mote_id, voltage,nexthop, globaltime); } 5. TENET EVALUATION This section evaluates Tenet through micro bench marks of its tasking and networking subsystems and reliable stream transport, and through four application studies, including a pursuer-evader game (PEG), an application believed to be particularly challenging to implement efficiently without in-network data fusion. We find that Tenet’s core mechanisms, such as tasking, scale well; that Tenets are robust and manageable; that its tasking language is flexible enough to accommodate a variety of applications; and that even challenging applications may be implemented with little efficiency loss. A) Concurrency for simple tasks is about 64 Sample(60000ms, 1, REPEAT, ADC0, A) -> Send() Max concurrency of Sample(20000ms, 1, REPEAT, 1, ADC0, A) -> LocalTime(B) -> Count(C, 0, 1) -> MeanDev(D, A) -> GT(E, A, 0) -> DeleteAttribute(A) -> Send()  is 32 on a Tmote B) Execution time for mean of multiple samples  Execution never CPU bound

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Input Samples Time (ms) ----------------------------------------------------1 1.8 40 2.3 400 6.8 800 11.9 1200 16.9 ----------------------------------------------------6. CONCLUSION We have demonstrated a complete, scalable, end-to-end imaging system to unobtrusively observe biological phenomena. Our deployment has shown that our system design has met most of the application requirements: ease of use, sufficient image transport rate, scalability exceeding that of wired cameras, and flexibility of deployment. This was made possible by using Tenet. Indeed, our TENET software can be used for other sensing applications as well. We have described a deployment of a network of wireless sensors on a suspension bridge, and have presented some preliminary results. In this article, we have shown that the Tenet architecture simplifies application development for tiered sensor networks without significantly sacrificing performance. By constraining multi-node fusion to the master tier, Tenet also benefits from having a generic mote-tier that does not need to be customized for applications. Our Tenet system is able to run applications concurrently, and our collections of task lets support data acquisition, processing, monitoring, and measurement functionality. Many interesting research directions remain: energy management, support for mobile elements, network congestion control, extending the task library to incorporate a richer tasklet set, and so forth. References [1] [2]

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S. Ahmadian, T. Ko, J. Hicks, M. Rahimi, D. Estrin, S. Soatto, and S. Coe. Heartbeat of a nest: using imagers as biological sensors. In submission to ACM Transactions on Computational Logic, April 2008. O. Gnawali, B. Greenstein, K.-Y. Jang, A. Joki, J. Paek, M. Vieira, D. Estrin, R. Govindan, and E. Kohler. The TENET Architecture for Tiered Sensor Networks. In Proc. 4th ACM International Conference on Embedded Networked Sensor Systems (SenSys’06), Boulder, Colorado,Nov. 2006. J. Paek and R. Govindan. RCRT: Rate-Controlled Reliable Transport for Wireless Sensor Networks. In Proc. 5th ACM International Conference on Embedded Networked Sensor Systems (SenSys’07), Sydney, Australia, Nov. 2007. M. Rahimi, R. Baer, O. I. Iroezi, J. C. Garcia, J.Warrior, D. Estrin, and M. Srivastava. Cyclops: In situ image sensing and interpretation in wireless sensor networks. In Proc. 3th ACM International Conference on Embedded Networked Sensor Systems (SenSys’05), pages 192–204, San Diego, California, Nov. 2005. Paek, J., Chintalapudi, K., Govindan, R., Caffrey, J., & Masri, S. 2005 (May). A Wireless Sensor Network For Structural Health Monitoring: Performance and Experience. In: Proc. of the Second IEEE Workshop on Embedded Networked Sensors. Abbasi, A.A., Younis, M., “A Survey on Clustering Algorithms for Wireless Sensor Networks,” Com- puter Communications, V30, pp.2826-2841, 2007. Greenstein, B., Kohler, E., and Estrin, D. 2004. A sensor network application construction kit (SNACK). In Proceedings of 2nd ACM International Conference on Embedded Networked Sensor Systems (SenSys’04). 69–80. Xu, N., Rangwala, S., Chintalapudi, K., Ganesan, D., Broad, A., Govindan, R., & Estrin, D. 2004 (November). A Wireless Sensor Network for Structural Monitoring. In: Proc. ACM Conference on Embedded Networked Sensor Systems. Levis, Philip, Patel, Neil, Culler, David, & Shenker, Scott. 2004 (March). Trickle: A Self-Regulating Algorithm for Code Propagation and Maintenance in Wireless Sensor Networks. In: First Symposium on Network Systems Design and Implementation, NSDI'04. Lynch, Jerome P., & Loh, Kenneth. 2005. A Summary Review of Wireless Sensors and Sensor Networks for Structural Health Monitoring. Shock and Vibration Digest, 38(2), 91.128. Doebling, S. W., Farrar, C. R., Prime, M. B., & Shevitz, D. W. 1996 (May). Damage Identi_cation and Health Monitoring of Structural and Mechanical Systems from Changes in their Vibration Characteristics: A Literature Review. Tech. rept. Los Alamos National Laboratory. Gnawali, Omprakash, Greenstein, Ben, Jang, Ki-Young, Joki, August, Paek, Jeongyeup, Vieira, Marcos, Estrin, Deborah, Govindan, Ramesh, & Kohler, Eddie. 2006 (November). The TENET Architecture for Tiered Sensor Networks. In: Proc. ACM Conference on Embedded Networked Sensor Systems. Culler, D., Dutta, P., Ee, C. T., Fonseca, R., Hui, J., Levis, P., Polastre, J., Shenker, S., Stoica, I., Tolle, G., and Zhao, J. 2005. Towards a sensor network architecture: Lowering the waistline. In Proceedings of 10th Hot Topics in Operating Systems Symposium (HotOS-X). 139–144. Dunkels, A., ¨Osterlind, F., and He, Z. 2007. An adaptive communication architecture for wireless sensor networks. In Proceedings of 5th ACM International Conference on Embedded Networked Sensor Systems (SenSys’07). Gnawali, O., Na, J., and Govindan, R. 2009. Application-informed radio duty-cycling in a re-taskable multi-user sensing system. In Proceedings of the 8th ACM/IEEE International Conference on Information Processing in Sensor Networks (IPSN’09). Greenstein, B., Mar, C., Pesterev, A., Farshchi, S., Kohler, E., Judy, J., and Estrin, D. 2006. Capturing high-frequency phenomena using a bandwidth-limited sensor network. In Proceedings of 4th ACM International Conference on Embedded Networked Sensor Systems (SenSys’06).

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Jeevarathinam A completed M.Sc M.Phil from Bharathiar University. Currently working as a lecturer in the department of Computer Science in Karpagam University. She has presented more than 5 papers in national conferences . Her research area includes network security ,sensor networks and digital image processing.

Lakshmi K has completed MCA M.Phil from Bharathiar University. Currently working as a lecturer in the department of Computer Application in Karpagam University. She has presented more than 5 papers in national conferences. Her research area includes network security, mobile computing.

Thilagam K has completed MCA M.Phil in Computer Science. Currently she is pursing Ph.D in Computer Science in Karpagam University, Coimbatore. She has 7 years of teaching experience. She has presented more than 5 papers in national conferences. Her research area includes image processing, data compression, stenography, digital image processing.

K. Rama, has completed M.C.A., M.Phil., from Bharathiar University. Currently working as a Lecturer in the department of Computer Science in Karpagam University. She has presented more than 7 papers in national conferences. Her research area includes digital image processing, stenography

Manju Priya .S has completed M.Sc, M.Phil in Computer Science from Bharathiar University, Coimbatore. She has 6 years of teaching experience. Currently she is pursing Ph.D in Computer Science in Karpagam University. She has presented more than 5 papers in national conferences. Her research area includes wireless sensor network, Computer communications.

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