What is MANET? Selfconfiguring network of mobile routers connected by wireless links. 1. Forms arbitrary topology. 2. R apid, apid, unpredictable topological changes
y
Each
device in a MAN ET is free to move independently in any direction, and will therefore change its links to other devices frequently. Each must forward traffic unrelated to its own use, and
y
therefore be a router . Characteristics y y y y
of MANET
No centralized control & administration Self-organizing and self-restoring ransmission through multiple multiple hops Transmission Frequent link breakage and change of network topology
Applications of MANET y y y y y
Battlefield
communication Sensor networks Personal area networking using PDAs, laptops and handphones, etc Search-and-rescue Cellular network and wireless Hot Spot extension
Problems y y
Without
a central infrastructure, things become much more difficult Problems are due to -: a) Lack of central entity for organization available b) Limited range of wireless communication c) Mobility of participants d) Battery-operated entities
What is WSN? A Wireless Sensor Network (WSN) consists of spatially distributed autonomous sensors to monitor physical or environmental conditions, such as temperature, sound, vibration, pressure, motion or pollutants and to cooperatively pass their data through the network to a main location
y
Application y
Physical
security for military operations
y
Indoor/Outdoor Environmental
y
Seismic and structural monitoring
y
Industrial
y
Bio-medical
y
Health and Wellness Monitoring
y
Inventory
y
Future consumer applications, including smart homes.
monitoring
automation applications
Location Awareness
Characteristics
y y y y y y y y y y
Power
consumption constrains for nodes using batteries or energ y harvesting Ability to cope with node failures Mobility of nodes Dynamic network topology Communication failures Heterogeneity of nodes Scalability to large scale of deployment Ability to withstand harsh environmental conditions Easy of use Unattended operation.
Similarities between MANET and WSN y
y
y
y
y
Both
are Distributed Wireless networks that is there is not a significant network infrastructure in place. outing between two nodes may involve the use of intermediate relay nodes also known R outing as Multihop Routing. Both Ad hoc and sensor nodes are usually battery-powered and therefore there is a big concern on minimizing power po wer consumption. Both networks use a wireless channel placed in an unlicensed spectrum that is prone to interference by other radio technologies techno logies operating in the same frequency. Self-management is necessary because of the d istributed nature of both networks.
Differences y
y
y
MANETs are usually ³close´ to humans, in the sense that most nodes in the network are devices that are meant to be used by human beings (e.g., laptop computers, PDAs, mobile radio terminals, etc.); conversely, sensor networks do not focus on human interaction but instead focus on interaction with the environment . The
number of nodes in sensor networks, as well as the d ensity ensity of d eployment eployment , can be orders of magnitude higher 1 than in ad hoc networks as the nodes in a sensor network are usually embedded in the environment to sense some phenomenon and possibly actuate upon it. Terms
such as unicast and multicast common in MANETs, are hardly applicable in WSN where we find other forms of routing such a s one-to-many, many-to-one, many-to-many, etc.
y
The
y
The
y
network size is case of a MANET depends upon no. of o f active users present in the extension of the Deployment area. But in WSN¶s the no. of nodes depends upon the extension observed area, characteristics of nodes and on required redundancy
traffic in MANET¶s are generally going to be higher owing to the use of well known services like Web, mail, video etc but in case of WSN¶s the d ata ata rate is low over a large period of time as WSN¶s interact with surrounding environment. In
evices (Laptop or a case of WSN¶s the sensor nodes are state of art computation d evices as in case of WSN¶s nodes are of o f simple and cheap elements implementing PDA) where as efficient algorithms.
y
WSN¶s
are conceivable with w ith different network d ensities ensities , from very sparse to dense deployments which will require different or least adaptive proto cols. This diversity although present, is not as quite large in MANET¶s.
y
In
both MANET¶s and WSN¶s energy is a scarce recourse. But WSN¶s have tighter requirements on network lifetime, and recharging o r replacing WSN¶s node batteries is much less an option opt ion then in MANET¶s. Owing to this, the impact of energy energ y considerations on the entire system architecture is much deeper in WSN¶s than in MANET¶s.
y
The
QoS services in a MANET is traditionally dictated by traditional applications (low jitter for voice applications) but for WSN¶s entirely new QoS is requires which also takes energy explicitly into account.
y
edundant R edundant
deployment makes d ata ata centric protocol very important in case of WSN¶s which is irrelevant and alien in case o f MANET¶s.
y
MANET¶s uses public key cryptography for security purposes but WSN¶s use Symmetric key cryptography.
y
Most nodes on WSN¶s applications have stationary nod es es compares to MANET¶s.
y
WSN¶s
y
are smaller, more powerful po werful and more memory constraine d compared to MANET¶s. Routing in MANET¶s support any node pairs, some source routing and distance vector protocols incur heavy control traffic but WSN¶s support specialized traffic pattern as they cannot afford to have too many node states and packet overhead.
y
WSN¶s
nodes are mostly prone to failure because of mobility as some WSN nodes requires mobility compared to MANET¶s.
y
The
main purpose of MANET is distributed computing but information gathering.
WSN¶s
are used for
