0-Ad Hoc Network_updated

8/3/2019 0-Ad Hoc Network_updated

http://slidepdf.com/reader/full/0-ad-hoc-networkupdated 1/25

ADHOC NETWORK



By.

P. Victer Paul

Dear,

We planned to share our eBooks and project/seminar contentsfor free to all needed friends like u.. To get to know about morefree computerscience ebooks and technology advancements incomputer science. Please visit....

http://free-computerscience-ebooks.blogspot.com/

http://recent-computer-technology.blogspot.com/

http://computertechnologiesebooks.blogspot.com/

Please to keep provide many eBooks and technology news forFREE. Encourage us by Clicking on the advertisement in theseBlog.

















Wireless Network

Wireless networks use some sort of radiofrequencies in air to transmit and receivedata instead of using some physical

cables.

Wireless Networking devices can operatein one of the two modes:

Infrastructure mode

Ad hoc modes



Infrastructure mode

Infrastructure mode wireless networkingbridges (joins) a wireless network to a wiredEthernet network.

A wireless access point (AP) is required for

infrastructure mode wireless networking. To join the WLAN, the AP and all wireless clients

must be configured to use the same SSID(Service Set Identifier, the name of the wireless

network that you wish to join). The AP is then cabled to the wired network to

allow wireless clients access to, for example,Internet connections or printers.



Infrastructure mode



Ad-Hoc Mode

ad-hoc mode is a method for wireless devices todirectly communicate with each other.

Operating in ad-hoc mode allows all wireless

devices within range of each other to discoverand communicate in peer-to-peer fashionwithout involving central access points.

To set up an ad-hoc wireless network, eachwireless adapter must be configured for ad-hocmode and must use the same SSID.



Ad-Hoc Mode



Ad hoc Network

Ad hoc has two definitions—thefirst can be either “impromptu”or “using what is on hand,”while the other is “for onespecific purpose.”

Ad hoc networks, which arealso called mesh networks , aredefined by the manner in whichthe network nodes are

organized to provide pathwaysfor data to be routed from theuser to and from the desireddestination.

All available nodes are aware

of all other nodes within range.



Routing Protocols

Routing protocols between any pair ofnodes within an ad hoc network can bedifficult because the nodes can move

randomly and can also join or leave thenetwork

Three categories that existing ad-hocnetwork routing protocols fall into:

1. Table Driven Protocols

2. On Demand Protocols

3. Hybrid Protocols



Ad-hoc Mobile Routing Protocols



Table Driven Routing Protocols

also known as Proactive Protocols work out routes in the background independent

of traffic demands.

Each node uses routing information to store thelocation information of other nodes in thenetwork and this information is then used tomove data among different nodes in thenetwork.

This type of protocol is slow to converge andmay be prone to routing loops.

Fisheye State Routing is an example of a Table

Driven Protocol.



On Demand Routing Protocols

also known as Reactive Protocols establish routes between nodes only when they are

required to route data packets.

When a route is required by a source node to a

destination for which it does not have routeinformation, it starts a route discovery processwhich goes from one node to the other until itarrives at the destination or a node in-between has

a route to the destination. On Demand Protocols more suited to large

networks with light traffic and low mobility.

An example of an On Demand Protocol is DynamicSource Routing.



Hybrid Routing Protocols

Combine Table Based Routing Protocols withOn Demand Routing Protocols.

Each node in the network has its own routing

zone, the size of which is defined by a zoneradius, which is defined by a metric such asthe number of hops.

Zone Routing Protocol (ZRP) is an exampleof a Hybrid routing protocol.



ad hoc wireless setup in a homenetwork

diagram illustrates use of a so-calledad hoc wireless setup in a homenetwork



Ad-Hoc Networking Features

Regardless of the application, there arecertain critical features that can determinethe efficiency and effectiveness of an ad-

hoc network.

These features can be categorized into

quantitative features and

qualitative features



Quantitative Critical Features

Network Settling Time

Network Join

Network Depart

Network Recovery Time

Frequency of Updates

Memory Byte Requirement

Network Scalability Number



Qualitative Critical Features

Knowledge of Nodal Locations

Effect to Topology Changes

Power Consciousness

Single or Multichannel Preservation of Network Security

QoS Routing and Handling of PriorityMessages

Real-time Voice Services

Real-time Video Services



Security in Ad-hoc Networks

Security Goals

Availability

Confidentiality

Integrity

Authentication



HOW TO SETUP WIRELESSADHOC NETWORK



Troubleshoot problems findingwireless

If Nodes does not detect a network thatyou think is in range of your computer, itcould be because of one the following

reasons: There is interference from other devices

The network you are looking for is set to

not broadcast its network name (SSID) Verify the SSID



Limitations of Ad Hoc Networks

While ad hoc networks are typically used wherethey have the greatest emphasis on its

advantages, there are some limitations: Each node must have full performance

Throughput is affected by system loading

Reliability requires a sufficient number of available

nodes. Sparse networks can have problems

Large networks can have excessive latency (timedelay), which affects some applications



Applications

Applications of Ad hoc networks.

Military battlefield networks

Personal Area Networks (PAN)

Disaster and rescue operation

Peer to peer networks

0-Ad Hoc Network_updated

Documents

Transcript of 0-Ad Hoc Network_updated