Presentation on theme: "SPIN : S ENSOR P ROTOCOL FOR I NFORMATION VIA N EGOTIATION SUBMITTED BY : SANCHAITA CHATTERJEE ROLL : 13000110041 CSE -4 TH YEAR."— Presentation transcript:
SPIN : S ENSOR P ROTOCOL FOR I NFORMATION VIA N EGOTIATION SUBMITTED BY : SANCHAITA CHATTERJEE ROLL : CSE -4 TH YEAR
CONTENT Data Centric Protocol SPIN Introduction Features Working Goal Two Basic Ideas Protocols SPIN-PP, SPIN-EC, SPIN-BC, SPIN-RL SPIN 1 and SPIN 2 Advantages Disadvantages Future Work Limitations Conclusion
DATA CENTRIC PROTOCOL Data centric protocols are query based and they depend on the naming of the desired data, thus it eliminates much redundant transmissions. The BS sends queries to a certain area for information and waits for reply from the nodes of that particular region. Depending on the query, sensors collect a particular data from the area of interest. This particular information is only required to transmit to the BS and thus reducing the number of transmissions SPIN was the first data centric protocol
SPIN - INTRODUCTION SPIN stands for Sensor Protocol for Information via Negotiation. SPIN uses negotiation and resources adaption to address the deficiencies of flooding. Negotiation reduces overlap and implosion. assign a high-level name to completely describe their collected data (called meta-data) Use three types of messages ADV (advertisement), REQ (request) and DATA.
INTRODUCTION CONTD … Designed to classify the deficiencies of classic flooding by negotiation and resource adaptation. Sending data that describe the sensor data instead of sending the whole data The sensor nodes that are interested in the data will get a copy. SPIN is based on data-centric routing – broadcast an advertisement of the available data and wait for a request from interested sinks.
SPIN- FEATURES Application-level Control Meta-data SPIN Message Resource Management Negotiation : to operate efficiently and to conserve energy using a meta-data. Resource adaptation : to extend the operating lifetime of the system monitoring their own energy resources.
A PPLICATION L EVEL C ONTROL Design motivated by Application Level Framing (ALF) network protocols must choose transmission units that are meaningful to application. packetization is best done in terms of application data units. Next step: routing decisions are also best made in application-controlled and application-specific ways using knowledge of not just network topology but also application data layout and the state of resources at each node. FEATURES – contd…
M ETA -D ATA Sensors use meta-data to describe the sensor data briefly Consider data X and data Y If x is the meta-data descriptor for data X sizeOf (x) < sizeOf (X) If x<>y sensor-data-of (x) <> sensor-data-of (y), i.e X<>Y If X<>Y meta-data-of (X) <> meta-data-of (Y) Meta-data format is application specific Data about data Example : Geographically disjoint sensors, may use their unique ID, say all data by sensor x Target tracking – signal energy + geographical location FEATURES – contd…
SPIN M ESSAGES ADV – advertise data REQ – request specific data DATA – requested data A B A B A B ADV REQ DATA FEATURES – contd…
Resource Management Sensors poll their system resources to find available energy. They can also calculate cost of performing computations. FEATURES – contd…
WORKING OF SPIN Resource adaptive algorithm When energy is plentiful Communicate using the 3-stage handshake protocol. When energy is approaching a low-energy threshold If a node receives ADV, it does not send out REQ Energy is reserved to sensing the event
WORKING OF SPIN CONTD …
S PIN : THE GOAL Broadcast with minimum energy
C ONVENTIONAL A PPROACH B D E F G C A Send to all neighbors E.g. routing table updates Flooding
R ESOURCE I NEFFICIENCIES 3. Resource Blindness 2. Overlap problem 1. Implosion Problem
Gossiping A C B D Forward data to a random neighbor Avoids implosion Disseminates information at a slower rate Fastest rate = 1 node/round
W HAT IS THE OPTIMUM PROTOCOL ? B D E F G C A “Ideal” Shortest-path routes Avoids overlap Minimum energy Need global topology information
T WO BASIC IDEAS The SPIN family of protocols rests upon two basic ideas: To operate efficiently and to conserve energy Nodes in a network must monitor and adapt to changes in their own energy resources to extend the operating lifetime of the system.
SPIN ON P OINT - TO -P OINT N ETWORKS SPIN-PP 3-stage handshake protocol Advantages Simple Minimal start-up cost SPIN-EC SPIN-PP + low-energy threshold Modifies behavior based on current energy resources
SPIN on Broadcast Networks One transmission reaches all neighbors SPIN-BC Same 3-stage handshake protocol as SPIN-BC Uses only broadcast communication Same transmission cost as unicast Coordination among nodes Broadcast message suppression sensor-data-of (x) = sensor-data-of (y) SPIN-RL SPIN-BC + Reliability Periodically re-broadcast ADVs and REQs
SPIN 1 AND SPIN 2 SPIN Resource Management Can make informed decisions about using their resources effectively Specifies an interface that applications can use to probe their available resources SPIN Implementation Implement the basis SPIN message types, message handling routines and, resource management functions Sensor applications can then use these libraries to construct their own SPIN protocols SPIN-1 : 3-Stage Handshake Protocol Simple handshake protocol for disseminating data through a lossless network Work in three stages (ADV-REQ-DATA) Computer Network21
SPIN 1 AND SPIN 2 SPIN-1 : 3-Stage Handshake Protocol Node A starts by advertising its data to node B (a). Node B responds by sending a request to node A (b). After receiving the requested data (c), node B then sends out advertisement to its neighbors (d), who in turn send requests back to B (e, f).
SPIN 1 AND SPIN 2 SPIN-2 : SPIN-1 with a Low-Energy Threshold Adds a simple energy-conservation heuristic to the SPIN-1 protocol When energy is plentiful, SPIN-2 nodes communicate using the same 3-stage protocol as SPIN-1 node When its energy is approaching a low-energy threshold, it adapts by reducing its participation in the protocol SPIN-1 : 3-Stage Handshake Protocol SPIN-1 can be run in a completely un-configured network with a small, startup cost to determine nearest neighbors. If the topology of the network changes frequently, these change only have to travel one hop before the nodes can continue running the algorithm.
ADVANTAGES Topological changes are localized - Each node needs to know only its neighbors provides more energy savings than flooding, and metadata negotiation almost halves the redundant data. Resource-adaptive enhancements. Outperforms gossiping. Seems better than flooding (solves data implosion and overlap). Simplicity Each node performs little decision making when it receives new data Need not forwarding table
DISADVANTAGES SPIN’s data advertisement mechanism cannot guarantee delivery of data. Large overhead Data broadcasting The paper does not consider collisions in the REQ stage Implosion problem still exists in REQ stage SPIN not good for applications that need reliable data delivery.
F UTURE WORK Consider the cost of not only communicating data, but also synthesizing data, make it more realistic resource- adaptation protocols. Queuing delay, loss-prone nature of wireless channels can be incorporated and experimented.
L IMITATIONS The SPIN EC(Energy Constrained) version’s strategy may be too simple. There should be a topology dependent strategy, e.g. a narrow bridge connecting two connected component should be more energy conservative. The ideal criteria used to compare with SPIN is ideal in terms of data dissemination rate, so really not ‘ideal’ anymore when energy or other resources are limited, need a new goal function.
CONCLUSIONS Successfully use meta-data negotiation to solve the implosion, overlap problem of simple flooding and gossiping. Resource-adaptive enhancements Simple scheme, small communication overhead, but a performance close to the ideal situation.
BIBLIOGRAPHY Negotiation based protocols for Disseminating Information in Wireless Sensor Networks by Joanna Kulik, Wendi Heinzelman, and Hari Balakrishnan