it is seminar ppt

1. • SEMINAR
WIRELESS MESH
NETWORK

2. HON. SHRI. BABANRAO PACPUTE VICHARDHARA TRUST'S
PARIKRAMA COLLEGE OF ENGINEERING, KASHTI ,
SHRIGONDAAHMEDNAGAR.
Seminar Presentation
On
• Wireless Mesh Network
By
Mahesh Nikam
Guide
Mrs.Kanade mam

3. INTRODUCTION
• Wireless Mesh Networks (WMNs) are dynamically self organised and self
configure ,with the nodes in the network automatically establishing an ad
hoc network and maintaining the mesh connection.
• A mesh network can be designed using a flooding technique or a routing
technique . When using a routing technique , the message is propagated
along a path , by hoping from node to node util the destination is reached.

4. CHANNEL ASSIGNMENT SCHEME
• In wireless mesh network, channel can be allocated between source
to destination and in between source and destination each router is
connected to its neighbour router in peer to peer manner, whole
channel consists of number of routers some of them use static
routing and others use dynamic routing scheme.
• Types of channel allocation scheme:
1.Static Channel allocation
2.Dynamic Channel Allocation
3.Hybrid Channel Allocation

5. DEFINATION
• “Wireless connect entire cities using inexpensive , existing
technologyA mesh network is a network that employs one of
two connection arrangements , full mesh topology or partial
mesh topology, In node is connected directly to each of others.
In the partial mesh topology , nodes are connected to only
some , not all , of the others nodes.”
• Wireless Mesh Networks(WMNs) are regard as an economical
alternative key technology for next generation wireless
networking.

6. DYNAMIC ALLOCATION
• In Dynamic channel allocation , an interface is allowed to switch
from one channel to another channel frequently.
• Dynamic Strategies require frequent channel switching and
thus have higher overhead than static strategies.
• The channel allocation can be changed with the changing
traffic.

7. ROUTING TREE CONSTRUCTION
• The basic tree construction process uses the metric by each WMN node to
determine a parent to achieve better load balancing , and load-aware
channel assignment.
• Gateway is used as central node which pass maximum traffic and it pass the
information to its directly connected node by sending advertisement
message and this advertisement message consists of costs directly
connected node.
• Other node which can receive the advertisement message can join or leave
the node. If the new node has less cost the old node then it can join the new
node and leave the old node. In this way shortest path is selected from
source to destination.

8. HYBRID CHANNEL ALLOCATION
• Both static and dynamic allocation have their own advantages
and disadvantages so we use hybrid architecture which is
combination of both , to can achieve better adaptively compare
to the pure static architecture without much increase of
overhead compare to the pure dynamic architecture.

9. BFS-CA(BREADTH FIRST SEARCH CHANNEL
ASSIGNMENT)
• represent edges between mesh radios instead of edges
between mesh routers which overcome the problem of both the
fixed and dynamic channel allocation scheme. This scheme is
based on interference – Aware channel assignment algorithm
improved the capacity of wireless mesh network by making use
of all available non-overlapping channels. This algorithm is
based on an extention to the conflict graph called the multi
radio conflict graph(MCG).

10. MULTI RADIO
• Mesh router can be equipped with multiple radios to perform
routing and access functionalities. This enables separation of
two main type of traffic in the wireless domain.
• Mesh routers improves the capacity of the network.
• Mesh radios help to mesh routers to send data to other nodes
by using different frequency.

11. MULTI-CHANNEL
• In WMNs multi-channel concept is used with multi-radio to
improve the capacity of network.
• By using multi radios every radio can be connected with
numbers of different channels.
• In this way number of non overlapping channel increases and
reduce the channel interference. Data can be send on different
channels without overlapping.

12. ROUTING PROTOCOLS
• A routing protocol specifies how routers communicate with each
other , disseminating information that enables them to select routers
between any two nodes on a computer network. Routing algorithm
determine the specific choice of route. Each router has a prior
knowledge only of networks attached to it directly.
• Types Of Routing Protocols
• 1.DSR
• 2.AODV
• 3.MR-LQSR

13. DSR-DYNAMIC SOURCE ROUTING
PROTOCOL
• This protocol is based on the concept of source routing. The
mobile nodes are required to maintain caches that contain
source routes of which it is aware. The entries in the route
cache are continually updated as new routes are learned.

14. WMNS STANDARDS
• IEEE 802.16a WMAN Mesh
• mesh mode in addition to the point-to-multipoint
(PMP) mode defined in IEEE 802.16.
• Operating in the licensed and unlicensed lower
frequencies of 211 GHz, allowing
non-line-of-sight (NLO) communications, spanning
up to a 50 km range.
• Supporting multi hop communications.
•

15. WMNS STANDARDS
• 802.11s WLAN Mesh
• Multi-hop capability added to 802.11g/a/b
• Auto configure on power up
• Multi-channel multi-radio operation
• Topology discovery
• MAC Path selection protocol
• Modified forwarding for QOS and mesh control
•

16. NETWORK ARCHITECTURE
• WMNs consist of two types of nodes Mesh Routers
and Mesh Clients
• Mesh router
• Additional routing functions to support mesh
networking.
• Multiple wireless interfaces with same or
different wireless access technologies.
• The gateway/bridge functionalities enable the
integration of WMNs with existing wireless
networks(cellular, sensor net, Wi-Fi, WiMAX).
• Mesh Clients
• Conventional nodes (e.g., desktops, laptops,
PDAs, Pocket PCs, phones, etc.) equipped with
wireless network interface cards (NICs), and can
connect directly to wireless mesh routers.
• Customers without wireless NICs can access WMNs
by connecting to wireless mesh routers through,
e.g., Ethernet.

17. DIAGRAM OF MESH TECHNOLOGY

18. ADVANTAGES
• requires only one node in the network to be physically wired for internet connection;
• provides collaborative, redundant backup technology, which ensures data security in the event of disk failure;
• is able to be configured dynamically for speed;
• uses less power;
• offers increased reliability, as each node is connected to several other nodes and, if one drops out of the
network, its neighbors simply find another route;
• uses the same set of standards as most Wi-Fi networks -- 802.11a, b and g;
• is scalable, as it is typically easy to add nodes to the network; and
• can effectively provide coverage to home Wi-fi mesh networks without reducing bandwidth, unlike Wi-Fi range
extenders.

19. DISADVANTAGES
• Networks with low processing capabilities may have more latency, as data
often must hop through several different nodes.
• The lack of a central server can make mesh systems more complicated to
monitor, control and troubleshoot.
• The lack of centralization can make routing and resource management
processes more complex than with other types of wireless networks.
• Initial network setup can be complex, as ideal node placement across different
points in the area will likely involve some trial and error.
• For homes, node devices can be less cost-effective than traditional
router/modem Wi-Fi networks.

20. CONCLUSION
• It can be concluded that Multi-Radio, Multi-Channel wireless
mesh topology is best over all other topologies which helps us
to improve the network performance by increasing network
throughput and decreasing the delay in the network.

21. REFERENCES
•
[1] Blackmore, S.(1994). Precision Farming: An Introduction. Outlook on Agriculture 23(4) 4, 275-280.
• [2] Ning Wang, Naiqian Zhang, Maohua Wang, “Wireless sensors in agriculture and food industry—Recent development and future perspective”,
published in Computers and Electronics in Agriculture 50 (2006) 1–14.
• [3] Akyildiz, I.F., Xudong Wang: A Survey on Wireless Mesh Networks, IEEE Communications Magazine (September 2005)
• [4] Azo Nanotechnology Article: “Precision Agriculture - Nanotech Methods Used, Such as ‘Smart Dust’, Smart Fields’ and Nano sensors:”
http://www.azonano.com/details.asp.ArticleID=1318
• [5] “SoilNet - A Zigbee based soil moisture sensor network” Project Group, Institute Of Chemistry And Dynamics Of The Geosphere (ICG), Agrosphere
Institute, ICG 4, Forschungszentrum Jülich GmbH, 52425 Jülich, http://www.fz-juelich.de/icg/icg-4/index.php.index=739
• [6] IEEE Std. 802.15.4-2003, Wireless Medium Access Control (MAC) and Physical Layer (PHY) Specifications for Low Rate Wireless Personal Area
Networks (2003)
• [7] CC2420: http://focus.ti.com/docs/prod/folders/print/cc2420. html
• [8] Kwang Koog Lee, Seong Hoon Kim, Yong Soon Choi, Hong Seong Park: A Mesh Routing Protocol using Cluster Label in the ZigBee Network, IEEE
International Conference on Mobile Adhoc and Sensor Systems (October 2006)
• [9] Ran Peng, Sun Mao-heng, Zou You-min, ZigBee Routing Selection Strategy Based on Data Services and Energybalanced ZigBee Routing, IEEE Asia-
Pacific conference on Services Computing (December 2006)
• [10] Ho-In Jeon, Yeonsoo Kim: Efficient, Real-Time Short Address Allocations for USN Devices Using LAA (Last Address Assigned) Algorithm, 9th
International Conference on Advanced Communication Theory (February 2007)