localization & management of sensor networks

1 April 11, 2023]Rushin $hah

April 11, 2023]Rushin $hah2

Localization & Management of Sensor Networks

Unit - 4

WSN

3

Localization & Management of

Sensor Networks

April 11, 2023]Rushin $hah

» Localization in Sensor Network»Network Management Requirement»Network Management Model

»Design Issue» Energy Harvesting in Sensor N/W


Network Management for Wireless Sensor NetworksUnit 9 of book

April 11, 20235

Network Management Requirement

]Rushin $hah

A computer communication network generally consists of three

components:

Physical devices

Links (wireless or wired link),

Network nodes (hub, bridge, switch, or router), and

Terminals and Servers;

Protocol; and

Information that is being carried, including applications.

However, the physical devices and protocols are not sufficient to

support effective operation of a communications network.

Network Management (NM) tools and techniques are also

required to help provision network services & ensure co-

operation of entities in the network.

April 11, 20236

Reasons for Management Function

]Rushin $hah

The reasons for management functions are mainfold and may be summarized as follows: There are many heterogeneous devices and software

entities that comprise the network, and some may fail. It is the NM responsibility:

- To determine when, where, and why the fault had occurred

- & how to restore these entities. ‘Optimization of system performance’ as a distributed

system require NM to collaborate in the process. For example, in some networks,

Congestion Control through admission control, by changing routes or through device upgrade

Occurs/done by NM functions.

April 11, 20237

Reasons for Management Function

]Rushin $hah

Cont…

For most networks, NM functions

can be used to gather and analyze the behaviour of

user interaction during network interface,

which is very important in planning the long-term

evolution of network capacity and its performance.


NM : Set of Functions

Network management consist of a set of

functions:

Continuous monitoring of Network status,

Detection of Network faults and abnormalities,

Manage, Control, and Help configured Network

components,

Maintain normal operation, and

Improve Network efficiency and application performance.


Why NM, considered as an Application? To perform the previous tasks, NM needs to

collect real-time information in network devices,

analyze the information, and

apply control based on the information.

Information is often organized as a Management Information Base

(MIB) in each network device.

Usually, there is an Agent in each device

To collect the information and

Report to a network management centre.

Therefore,

“Network Management can be considered as an application.”

April 11, 202310

Simple Network Management Protocol

]Rushin $hah

For managing networks, SNMP is broadly use today.

It includes three components: Network Management System (NMS), Managed Elements, and Agents.

Role of NMS : NMS is a set of applications that monitor and/or control

managed elements. NMS can request management information/attributes

from the agent. NMS present the results to NM users in figures/tables

form. NMS can also set attributes within the agent.

SN

MP


Simple Network Management Protocol Role of Managed Element :

“ The managed elements are the network devices that are

managed ”.

SNMP agents run on each managed element.

The managed elements:

Collect & Store management information in the MIB and

Provide access through SNMP to the MIBs.

Examples: of managed elements include: Routers, Switches, Servers, and Hosts.

SN

MP

SwRo SeHo


Simple Network Management Protocol Role of Agents :

SNMP agents are management software modules that reside

on managed elements.

The Agents:

Collect and Store the state of the managed elements

Translate this information into a form compatible with

SNMP MIB.

Exchanges of network management information are through

messages called protocol data units (PDUs).

PDU are sent to nodes and

contain variables that have both attributes and values.

SN

MP



The SNMP defines five types of messages or PDUs:

Two deal with the reading terminal,

Another two handle terminal configuration, and

The fifth is Trap, used to monitor events in the managed

elements.

Each PDU contains both Attributes and Values.

Importance of PDU:

NM information can be exchanged through the PDUs in

order to monitor the managed elements.

SN

MP



Advantages of SNMP:

Its very simple and widely deployment.

In SNMP version 3 it can obtain more information by a

pair of PDUs such as (GetBulkRequest and GetResponse).

SN

MP



Disadvantages of SNMP :

It consumes considerable bandwidth since it often gets

only one piece of management information at a time:

GetRequest (GetNextRequest) and GetResponse.

Due to the usually large number of managed elements,

large bandwidth consumption still exists.

It only manages network elements; it does not support

network-level management.

SN

MP


Telecom Operation Map It is proposed by TeleManagement Forum.

It is based on the

Service management Network management

process models.

TOM presents a model for telecommunications management

for network and service management and a view of

‘‘operations.’’

IDEA:

To introduce processes comprising operations and their

automation.

TOM only provides a framework for service management.

TO

M


Telecom Operation Map : Levels / Layers

Vertical Layers for service management:

Network and Systems Management,

Service Development and Operations, and

Customer Care Process.

Horizontally Layers for service management

Service Fulfilment,

Service Assurance, and

Service Billing.

TO

M


Funda

Neither SNMP nor TOM is designed particularly for

wireless sensor networks.

However, by utilizing

The Simplicity of SNMP and

The Layered Framework of TOM

Design of effective & efficient n/w management

architecture for Wireless Sensor Networks is possible.

SN

MP

& T

OM


Network Management Design Issues

Requirement of NM in WSN:

WSN is a special type of wireless network:

possibly with ad hoc structure and

probably with limited resources.

Due to these WSN constraints: networking protocols, the

application model, middleware and sensor node OS

(operating systems) should be designed very carefully.

So here, Network management for WSNs is required to

use those limited resources effectively & efficiently.

20

Network Management Design Issues


Importance of NM in WSN: is for following reasons: (Design

Issue)

1. In order to deploy an Adaptive and Resource-Efficient algorithm in

WSNs, the current resource level needs to be gathered through

network management.

- For example: the power availability should be known before

switching a sensor node from active (or sleep) mode to sleep (or

active) mode.

- Most traditional networks do not have these requirements.

2. Collaboration and Cooperation between sensor nodes are required

to optimize system performance.

- Network management is an effective tool to provide the platform

required for this purpose.

The number are issue


Network Management Design Issues3. Most WSN applications need to know the coverage area

so that they ensure that the entire space is being

monitored.

- Topology management can be used in case an

uncovered area is detected.

- Approaches to increasing the coverage area:

I. Increase the node’s radio power,

II. Increase the density of deployment of senor nodes,

and

III. Move the sensor nodes around to achieve equal

distribution.

4. Nodes in WSNs are usually arranged in an ad hoc

manner. - The parameters of this ad hoc network are obtained by the network management system.

The number are issue


An issue is whether in the meanwhile, any of the existing network

management solutions (e.g., SNMP, TOM) can be used for WSNs.

SNMP is often used to manage network elements such as switches

and routers.

It uses GetResponse and GetResponse PDUs to collect information

from network elements.

In SNMP, a local management agent should run in each managed

element.

The local agent is a static and passive agent that receives

commands from a manager and returns the corresponding

response.

For Reference


It can also issue Trap messages to the manager when the managed

element encounters a preconfigured event.

Agents in different network elements are independent, and there is

not collaboration among them.

TOM is a new operation and management model that provides a

layered architecture for management and administration.

Each layer has a different management function and set of managed

objects.

TOM can be used to manage most tasks, from the underlying physical

network element to the entire network, as well as the services

provided.

For Reference


SNMP provides five management functions: fault management,

configuration management, accounting management,

performance management, and security management; and

TOM, the management functions are layered in network element

management, network management, and service management.

In each layer, different management functions are embodied.

WSNs need some of these management functions.

Therefore, WSNs need layered management architecture with

different management functions in each layer.

For Reference


The issue of management architecture for WSNs should also be considered

carefully.

A network management platform consists of three major components:

manager, agent, and MIB.

The manager is used to manage and control the entire network and works

as an interface to other systems.

The agent is located in managed elements.

MIB is an object-oriented structured tree that informs the manager and

agent about the organization of management information.

A standardized MIB guarantees that the management products from

different vendors interconnect.

The manager receives management information and commands the

managed elements using a SNMP-like method or mobile-agent-based

entities.

For Reference


The method of accessing management information and the

placement of the manager or agent usually determines the

management architecture.

The agent-based method can save bandwidth since it can

report only final management information.

Although WSNs have a centralized data collecting point

(sink), they are more like distributed networks.

As a result, agent-based hybrid management architectures

might be more suitable for WSNs.

For Reference


In WSNs, management information can be used to improve

system performance.

For example, if the network management system detects a

dysfunctional sensor node, it can command another sensor

node to take over.

So the issue of integration of network management with

the functions of network protocols and algorithms becomes

critical.

For Reference


Which factors should be consider while designing a

Network Management Protocol ?

29

Special Features of WSNs in NM function.


Management solutions should be energy efficient, using as little

wireless bandwidth as possible since communication is highly energy

demanding.

Management solutions should be scalable. This is especially important

since in future WSNs may consist of tens to thousands of nodes.

Management solutions should be simple & practical since WSNs are

resource-constrained distributed systems.

MIB for WSNs should contain a general information model for sensor

nodes, features of WSNs and WSN applications.

Management solutions for WSNs should provide a general interface

to the applications since applications can perform better when able to

access management information.

Management solutions should be implementable as middleware.

April 11, 202330

MANNA : Management Architecture

]Rushin $hah

An optimization problem for monitoring, management

provides the monitoring regions given that the ‘battery and

energy consumption rate for each sensor are known

beforehand’.

Mo

nit

ori

ng

Man

ag

em

en

t

MANNA is a management

architecture for WSNs

proposed by Ruizetal.

The architecture considers

three management

dimensions:

Management Function

Areas,

Management Levels, and

WSN Functionalities


MANNA : Management dimensionsManagement Function Areas Management Levels

Similar to those in SNMP

Fault mng,

Configuration mng,

Performance mng,

Security mng, and

Accounting Management

NOTE: Configuration management has a notably more important

role in MANNA, where all other functions depend on it.

Similar to those in TOM

Network Element,

Network Element

Management,

Network Management,

Service Management, and

Business Management.

FCPAS

Five types of traditional management functions similar to SNMP:


MANNA : Management dimensions

A number of other functions are proposed by MANNA:

Configuration,

Maintenance,

Sensing,

Processing, and

Communication.

With the Aim of promoting productivity and integrating the

functions of configuration, operation, administration and

maintenance of all elements and services in a WSN

- MANNA architecture includes three architectural elements:

Functional, Physical, and Informational architectures.Mo

nit

ori

ng

Man

ag

em

en

t

ProCoMaSeComm

PLZ!


MANNA : Architectural Element

Functional architecture:

- It provides functions executed in

the management entities (manager, agent, and MIB) and

the location scheme for managers and agents.

Physical architecture:

- It is where functional architecture is implemented.

- MANNA uses a lightweight protocol as a communication

interface between management entities.

Information architecture:

- The Architecture element provides an object-oriented model

for mapping manageable resources and supporting object

classes.


MANNA : Managed Object Classes

Network (information on network behaviour and features

such as data delivery model, network structure, and

mobility),

Managed elements (such as sensor nodes),

Equipment (the physical components of sensor nodes),

System (information on operating system),

Environment (the environment the WSN is running),

Phenomenon, and

Connection.


MANNA : Common Management Functions

An Environment monitoring functions,

A coverage area supervision function,

A topology map discovery function,

An energy-level discovery function,

An energy map generation function, and several others.


MANNA : dynamic MIB model

MANNA also provides a dynamic MIB model for WSNs:

A sensing coverage area map,

A communication coverage area map,

A WSN behaviour model,

A node dependence model,

network topology,

residual energy, and so on.

In MANNA, the management functions have the lowest

granularity and can be combined into management

services.

-1st sense then communication coverage area map.-Then create two model : behaviour & node dependence-Now define network topology and residual energy


Issues Related to Network Management The most important issues in Network

management areI. Naming,II. Localization,III. Maintenance, andIV. Fault tolerance.


Meaning of Each IssueД Naming is the scheme used to identify a sensor node.

-An efficient naming scheme can lower computation overhead and

make routing protocol energy efficient.

Д Localization schemes determine the location of sensor nodes since

such information is important for some sensor applications.

Д The maintenance issue may involve actions such as replacing

batteries, keeping connectivity, and configuring sensor nodes.

-The maintenance activity is used to maintain normal operation of

the entire network for as long as possible.

Д Several factors can cause faults in network operation, including

hardware and software error. Therefore, different schemes must be

implemented to provide fault tolerance.

April 11, 202339

Naming

]Rushin $hah

A node in a networked system is identified through

Naming.

This identifier is then used for communication between

nodes.

Approaches to Naming: Low-level naming such as node addresses is typically

application independent but topology and location dependent.

High-level naming is usually application dependent and location independent.

High-level Naming is built on the top of Low-level

Naming.

Communication between applications uses high-level

naming only, whereas physical communication relies on

low-level naming.

Therefore, a binding mechanism is required to realize

mapping bbetween high- and low-level naming.

April 11, 202340

Naming

]Rushin $hah

For example: the domain name system (DNS) in the

Internet uses two types of naming: a domain name and an

IP address.

The domain name is used by applications such as

Internet browsers.

The IP address is used by routing protocol to guarantee

packet forwarding.

Domain name and IP addresses are often directed to the

same host. The DNS servers map between domain

names and IP addresses.

When a Web site is accessed using a domain name, the

application program requests a corresponding IP address

from the DNS so as to set up low-level communications.

April 11, 202341

Naming : traditional hierarchical naming advantages

]Rushin $hah

Although the traditional hierarchical naming approaches

can be used for WSN, but not efficient compared with

application oriented low-level naming, which has the

following advantages: It avoids the overhead resulting from mapping between

high- and low-level naming. This feature is attractive for a sensor since it has limited resources.

Location-dependent addressing is not required. Since the topology of WSNs is highly variable due to node mobility, node life span, and wireless channel quality, a location-dependent address would cause additional problems.

It enables application-specific processing in the network, such as data compression and data fusion, which in turn reduces data transmission.


Sensor nodes are usually classified by the type of data they

gather.

For sensor nodes that gather only one type of data or can

have differing personalities and gather multiple types of

data, one name as their identifier would be sufficient.

The objective of low-level application naming is to realize

energy efficiency and fault tolerance in a variety of

environments.

April 11, 202343

Localization

]Rushin $hah

Sensor nodes are distributed all over the place

for sensing and data collection.

It is usually helpful if the locations of sensor

nodes are also known.


Localization : Advantages of Location Knowledge

Some applications, such as those for tracking of objects, are

highly location dependent;

Location-based Routing, which may also result in energy

conservation is enabled;

Knowledge of location usually enhances security;

Locations are helpful for sensor network management and

monitoring;

Locations stimulate the creation of new applications;

Sensor nodes that move can be controlled through knowledge of

their location; and

For applications with low-level naming and/or data-centric WSNs,

knowledge of location information is absolutely necessary.


Localization : Classification

Localization

Algorithm

Centralized

Schemes

Distributed

Schemes

Range-based

Scheme

Range-free

Schemes



Centralized Scheme

In this scheme Sensor nodes send control messages to a

central node whose location is known.

The central node then computes the location of every sensor

node and informs the nodes of their locations.

Distributed Scheme

Each sensor node determines its own location independently.

The distributed localization can be further grouped into:

Range-based schemes and

Range-free schemes.



In the range-based approach, some range information, such

as time of arrival, angle of arrival, or time difference of

arrival is required.

The range-free algorithms works as follows:

Several seed nodes are distributed in WSNs.

Seed nodes know their own locations, and they

periodically broadcast a control message with their

location information.

Sensor nodes that receive these control messages can

then estimate their own locations.


Last PPT of S

IR

Lecture -38

Localizatio

n


Introduction

The development of large scale distributed sensor

system is a significant scientific and engineering

challenge.

By placing sensors close to each other can increase

signal quality at reduce cost.


Taxonomy of localization

Commonly localization is divided in two major

categories

1. Active Localization

2. Passive Localization


Active Localization

Active localization technique emit signals into the

environment that are used to measure range to the

target.

These signals may be emitted by infrastructure

components or by targets.

Within this category of active localization there are

three subcategories.

1. Non-cooperative target

2. Co-operative target

3. Co-operative infrastructure


Non Co-Operative Target

In active Non Co-operative system, system elements

(Sensors) emit ranging signals, which are distorted or

reflected in flight by passive elements.

The system element then receive the signals and

analyze them to deduce their location relative to

passive elements of the environment.

Example includes RADAR System and SONAR systems

in robots.


Co-Operative Target

In co-operative target system, targets emit signal with

known characteristics and other element of the

system detects the signal and use information about

signal arrival to deduce the target’s location.


Co-Operative Infrastructure

In co-operative infrastructure system, elements of the

infrastructure emit signals that target can receive.

The infrastructure itself is assumed to be carefully

configured & synchronized to simplify the processing

done by the target.


Passive Localization

Passive localization techniques differ from active ones in

that they discover ranges and locations by passively

monitoring existing signals in a particular channel.

The term passive does not imply that they emit no signals,

instead of that the signals they emit are out side the

channel that is primarily analyzed for time-of-flight

measurement.

1. Blind source localization

2. Passive Target Localization

3. Passive Self-Localization


Blind source Localization

In a blind source localization system, a signal source

is localized without any priori knowledge of the type

of signal emitted.

Typically this is done by “blind beam forming”,

which effectively cross-correlates the signals from

different receivers.


Passive Target Localization

Passive target localization system is usually based on

coherent combination of signals, with the added

assumption of some knowledge of the source.

By assuming model for the signals generated by the

source, filtering can be applied to improve the

performance of the algorithm.


Passive Self Localization

In passive self-localization , existing beacon signals

from known infrastructure elements are used by

Target to passively deduce its own location.


Localization challenges in Multi hop ad-hoc sensor Networks

Physical layer challenges

Algorithm Design Challenge

- Noisy measurement

- Computation and Communication trade-offs

- Problem setup

localization & management of sensor networks

Education