MCA-213
Wireless Sensor Networks
Networks of small battery-powered sensors — node architecture and operating systems, MAC and routing under an energy budget, and the applications they serve.
- Semester
- Semester 3
- Credits
- 3
- Scheme
- 3 lectures a week
- Contact hours
- 40 across four units
- Category
- Core Elective - II
What the paper is
Wireless Sensor Networks is Computer Networks under a constraint: every node is small, battery-powered and expected to run unattended for a long time. Almost every design decision in the paper follows from that, and the recurring question is what a protocol costs in energy rather than in throughput.
The paper builds bottom-up — the radio channel, then the node, then the operating system, then the MAC, network and transport layers — and each layer is revisited for how it is different from its wired equivalent. TinyOS in Unit II is the concrete operating system, and it is genuinely unlike the ones from the first semester.
Unit IV is the payoff: structural health monitoring, traffic control, medical and military applications, habitat monitoring, precision agriculture and underground mining, plus the simulation platforms — TOSSIM, ns-2, Avrora, OPNET, QualNet — used to evaluate any of it.
What to concentrate on
- Energy efficiency is the thread through the whole paper. For any protocol you are asked about, be ready to say where its energy goes and what it trades away to save some — that framing answers most long questions.
- The comparison between a WSN and an ad hoc network is a standing question in Unit I and a good organising answer: scale, energy, addressing, mobility and data-centric versus address-centric routing.
- For Unit III, cluster-based and hierarchical routing — LEACH-style protocols — and data-centric routing are the most examined. Know why flooding and gossiping are the baselines they are compared against.
Syllabus, unit by unit
Summarised from the approved scheme. Hours are the contact hours the scheme allots, which is a fair guide to where the marks sit.
Unit I · Wireless fundamentals and node architecture
10 hours- Fundamentals of wireless communication, the electromagnetic spectrum, radio propagation, characteristics of wireless channels
- Modulation and multiple access techniques; wireless LANs, PANs, WANs and MANs; the wireless internet
- Characteristic requirements and challenges for WSNs; WSNs versus ad hoc networks
- Sensor node architecture: sensing subsystem, processor subsystem, communication interfaces
- Prototypes: IMote, IRIS, Mica Mote, EYES nodes, TelosB
Unit II · Operating systems, topology and medium access
10 hours- Operating systems: scheduling, data types, stacks, system calls, memory allocation, interrupt handling; TinyOS and LA-TinyOS
- Wireless communication characteristics: link quality, fading, shadowing, localisation
- Connectivity and topology: sensor deployment mechanisms, coverage issues, node discovery protocols
- Medium access protocols: energy efficiency, power allocation and medium access control issues
Unit III · Network and transport layers
10 hours- Routing metrics, flooding and gossiping
- Data-centric routing, cluster and hierarchical routing protocols
- Energy-efficient routing, location-based routing, QoS-based routing
- Transport protocol design issues and the performance of transport control protocols
Unit IV · Middleware, security and applications
10 hours- Middleware and application layer: data dissemination, data storage, query processing
- Security: issues, attacks and countermeasures; IEEE 802.15.4 and Zigbee security
- Applications: structural health monitoring, traffic control, highway monitoring, medical and military applications, wildfire instrumentation, habitat monitoring, home control, building and industrial automation, precision agriculture, underground mining
- Simulation platforms: TOSSIM, ns-2, Avrora, OPNET, QualNet
How it is examined
- Question 1 is compulsory, covers the whole syllabus, and is made of objective or short-answer questions. It carries 12 marks.
- The rest of the paper is four units matching the four above. Each unit sets two questions and you attempt one, so there are four more answers at 12 marks each.
- Examiners are asked to map every question to a course outcome using Bloom's taxonomy, which is why questions are phrased as “apply”, “analyse” or “evaluate” rather than only “explain”.
The pass mark is 40 out of 100 in every paper.
Learning objectives
- The basics of wireless communication and wireless sensor networks
- Protocols at the different layers of a wireless sensor network
- The applications of wireless sensor networks
Assumed beforehand
- Computer Networks
Paired in the scheme with MCA-265 Lab based on Core Elective II.
Books it is taught from
- TB1Fei Hu and Xiaojun Cao, “Wireless Sensor Networks: Principles and Practice”, Auerbach Publications, 1st edition, 2010
- TB2C. S. Raghavendra, Krishna M. Sivalingam and Taieb Znati, “Wireless Sensor Networks”, Springer, 1st edition, 2006
Notes for MCA-213
Lecture notes, question papers and assignments filed against MCA-213 are in the library. Everything there has been checked by a moderator before it appears, and an account is free — new ones are approved by hand, which is what keeps the shelf clean.