International Journal of Engineering Trends and Technology (IJETT) – Volume 4 Issue 10-Oct 2013
Design & Implementation Of DAA Protocol
Mr.P.Anilkumar#1, Mr. K. Sudhakar*2
#
M.Tech Student, Department of ECE & St.John’s College of Engineering & Technology
Yerrakota, Yemmiganur, Kurnool,A.P,India
Abstract— False data can be injected by compromised sensor
nodes in various ways, including data aggregation and relaying
in wireless sensor networks. Since data aggregation is essential to
reduce data redundancy to improve data accuracy, false data
detection is critical to the provision of data integrity and efficient
utilisation of battery power and bandwidth. To support
confidential data transmission, the sensor nodes between two
consecutive data aggregators verify the data integrity on the
encrypted data rather than the plain data. Performance analysis
as shows that DAA detects any false data injected up to ‘T’
compromised nodes, and that the detected false data are not
forwarded beyond the next data aggregator on the path. Despite
that false data detection and data confidentiality increases the
communication overhead; simulation results shows the DAA can
still reduce the amount of transmitted data up to 60% with the
help of data aggregation and early detection of false data. The
main objectives of this paper are- false data detection, integrate
the detection of false data with data aggregation and
confidentiality, to present the novel security protocol DAA to
integrate data aggregation, confidentiality and false data
detection and to reduce the amount of transmitted data over the
wireless sensor networks with the help of data aggregation and
early data detection of false data, to a significant improvement in
bandwidth utilisation and energy consumption. Compromised
sensor nodes in wireless sensor networks, can distort the integrity
of data by injecting false data. Previously known techniques on
false data detection do not support data confidentiality and
aggregations, even though they are usually essential to wireless
sensor networks. However, this paper has presented the novel
security protocol DAA to integrate data aggregation,
confidentiality and false data detection.
Keywords— DAA, Data integrity, network-level Security,
confidentiality, aggregation, bandwidth.
I.
INTRODUCTION
Wireless sensor networks are vulnerable to many types of
security attacks, including false data injection, data forgery,
and eavesdropping. Sensor nodes can be compromised by
intruders, and the compromised nodes can distort data
integrity by injecting false data. The transmission of false data
depletes the constrained battery power and degrades the
bandwidth utilization. False data can be injected by
compromised sensor nodes in various ways, including data
aggregation and relaying. Because data aggregation is
essential to reduce data redundancy and/or to improve data
accuracy, false data detection is critical to the provision of
data integrity and efficient utilization of battery power and
bandwidth. In addition to false data detection, data
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confidentiality is required by many sensor networks
applications to provide safeguard against eavesdropping.
Fig.1 forming sensor pairs
Above Fig. 1 is an example of forming sensor pairs to
authenticate data for the false data detection scheme in, where
data aggregation is not allowed if it requires any change in the
data.
This Work is the first of its kind to integrate the detection
of false data with data aggregation and confidentiality. Data
confidentiality prefers data to be encrypted at the source node
and decrypted at the destination. However, data aggregation
techniques usually require any encrypted sensor data to be
decrypted at data aggregators for aggregation. The existing
false data detection algorithms address neither data
aggregation nor confidentiality. Although they could be
modified easily to support data confidentiality, it is a
challenge for them to support the data aggregation that alters
data. For instance, the basic idea behind the false data
detection algorithm in is to form pairs of sensor nodes such
that one pair mate computes a message authentication code
(MAC) of forwarded data and the other pairmate later verifies
the data using the MAC, as illustrated in Fig. 1. In this scheme,
any data change between two pairmates is considered as false
data injection, and therefore, data aggregation is not allowed if
it requires alterations in the data. Hence, the false data
detection algorithm cannot be implemented when a data
aggregator between two pairmates changes the data.
Data aggregation is implemented in wireless sensor
networks to eliminate data redundancy, reduce data
transmission, and improve data accuracy. Data aggregation
results in better bandwidth and battery utilization, which
enhances the network lifetime because communication
constitutes 70% of the total energy consumption of the
network. Although data aggregation is very useful, it could
cause some security problems because a compromised data
aggregator may inject false data during data aggregation.
When data aggregation is allowed, the false data detection
technique should determine correctly whether any data
alteration is due to data aggregation or false data injection. A
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International Journal of Engineering Trends and Technology (IJETT) – Volume 4 Issue 10-Oct 2013
joint data aggregation and false data detection technique has
to ensure that data are altered by data aggregation only.
This Work introduces a data aggregation and
authentication protocol (DAA) to provide false data detection
and secure data aggregation against up to T compromised
sensor nodes, for T>=1 . The value of T depends on security
requirements, node density, packet size, and the amount of
tolerable overhead.
In this Work it has been assumed that some sensor nodes
are selected dynamically as data aggregators, and the nodes
between two consecutive data aggregators are called
forwarding nodes simply because they forward data. To detect
false data injected by a data aggregator while performing data
aggregation, some neighbouring nodes of the data aggregator
(called monitoring nodes) also perform data aggregation and
compute MACs for the aggregated data to enable their pair
mates to verify the data later.
DAA also provides data confidentiality as data are
forwarded between data aggregators. To provide data
confidentiality during data forwarding between every two
consecutive data aggregators, the aggregated data are
encrypted at data aggregators, and false data detection is
performed over the encrypted data rather than the plain data.
Whenever the verification of encrypted data fails at a
forwarding node, the data are dropped immediately to
minimize the waste of resources such as bandwidth and
battery power due to false data injection.
A. Objectives of the Work
The main objectives of the Work are
 False data detection.
 To integrate the detection of false data with data
aggregation and confidentiality.
 To present the novel security protocol DAA to integrate
data aggregation, confidentiality, and false data
detection.
 To reduce the amount of transmitted data over the
wireless sensor network with the
help of data
aggregation and early detection of false data, to a
significant improvement in bandwidth utilization and
energy consumption.
II.
DESIGN OF DAA PROTOCOL
Wireless sensor networks are usually deployed in remote
and hostile environments to transmit sensitive information,
sensor nodes are prone to node compromise attacks and
security issues such as data confidentiality and integrity are
extremely important. Hence, wireless sensor network
protocols, e.g., data aggregation and authentication protocol,
must be designed with security in mind.
This Work presents a data aggregation and authentication
protocol (DAA) to provide false data detection and secure
data aggregation against up to T compromised sensor nodes.
Data aggregation techniques usually require any encrypted
sensor data to be decrypted at data aggregators for aggregation.
Data confidentiality prefers data to be encrypted at the source
node and decrypted at the destination. Data aggregation is the
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process of summarizing and combining sensor data in order to
reduce the amount of data transmission in the network.
A System Architecture of DAA
. To support false data detection, secure data aggregation,
and confidentiality against up to T compromised sensor nodes,
DAA forms 2T+1 pairs of sensor nodes by the neighbouring
and forwarding nodes of Au and Af.
This Work introduces a data aggregation and
authentication protocol (DAA) to provide false data detection
and secure data aggregation against up to T compromised
sensor nodes, for T ≥ 1. The value of T depends on security
requirements, node density, packet size, and the amount of
tolerable overhead. We assume that some sensor nodes are
selected dynamically as data aggregators, and the nodes
between two consecutive data aggregators are called
forwarding nodes simply because they forward data.
To detect false data injected by a data aggregator while
performing data aggregation, some neighboring nodes of the
data aggregator (called monitoring nodes) also perform data
aggregation and compute MACs for the aggregated data to
enable their pair mates to verify the data later. DAA also
provides data confidentiality as data are forwarded between
data aggregators.
To provide data confidentiality during data forwarding
between every two consecutive data aggregators, the
aggregated data are encrypted at data aggregators, and false
data detection is performed over the encrypted data rather than
the plain data. SYSTEM Design
III.
SYSTEM DESIGN
A. Introduction
System design is the stage of the Work when the
theoretical design is turned out into a working system. Thus it
can be considered to be the most critical stage in achieving a
successful new system and in giving the user, confidence that
the new system will work and be effective. This stage
involves careful planning, investigation of the existing system
and it’s constraints on implementation, designing of methods
to achieve change over and evaluation of changeover methods.
B. Block Diagram
Fig. 2 shows the functional block diagram of DAA
protocol. It contains the following modules,
 Networking Module.
 Stream Module.
 Message authentication codes Module.
 Key recovery Module.
 Authentication Module.
1) Networking Module: Client-server computing or
networking is a distributed application architecture that
partitions tasks or workloads between service providers
(servers) and service requesters, called clients. Often clients
and servers operate over a computer network on separate
hardware.
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International Journal of Engineering Trends and Technology (IJETT) – Volume 4 Issue 10-Oct 2013
Monitoring Server
Server
Router
IP
Address
Cryptographic
scheme
File
transfer
File
receive
Client
IP
Address
Cryptographic
scheme
Fig. 2 Block Diagram of the System
Fig. 2 shows the functional block diagram of DAA
protocol. It contains the following modules,
 Networking Module.
 Stream Module.
 Message authentication codes Module.
 Key recovery Module.
 Authentication Module.
1) Networking Module: Client-server computing or
networking is a distributed application architecture that
partitions tasks or workloads between service providers
(servers) and service requesters, called clients. Often clients
and servers operate over a computer network on separate
hardware.
A server machine is a high-performance host that is running
one or more server programs which share its resources with
clients. A client also shares any of its resources; Clients
therefore initiate communication sessions with servers which
await (listen to) incoming requests. To support data
aggregation along with false data detection, the monitoring
nodes of every data aggregator also conduct data aggregation
and compute the corresponding small-size message
authentication codes for data verification at their pair mates.
2) Streaming Module: A stream cipher is a symmetric
encryptor (i.e., the transmitter and receiver share the same
secret key). The key forms a seed which generates a
pseudorandom key-stream. At the transmitting end, this key
stream is XOR-ed with the clear text stream, yielding a cipher
text stream. The receiver, having the same seed key, generates
synchronously the same key-stream. XOR-ing with the
received cipher text yields the clear text back. Stream ciphers
operate at a higher speed than block ciphers and have
relatively low hardware complexity.
3) Message authentication codes Module: A short section of
the output is stored, without entering a long key-stream into a
CRC circuitry; the one-way feature of the transformation is
still kept. However, a relatively short string does not exhibit
randomness properties and rather represents a limited event
that may have a problematic pattern. Therefore, generating a
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relatively long key-stream and entering it into a CRC circuitry,
which preserves the randomness of its input, is desired.
4) Key recovery Module: Recovering S from a compressed
version of the cipher’s output key-stream, even if the
compression is based on a simple linear CRC, cannot have a
lower complexity than the recovery of S from a fully given
key-stream. As the latter is expected to be infeasible for
secure cipher, the irreversibility of the transformation is at
least as strong as the underlying security of the cipher.
5) Data aggregation and Authentication Module: MAC (M K)
is a one-way transformation of the message M and a secret
key K. The implementation this transformation can be based
on various approaches. Hash Message Authentication Code
(HMAC) is a hash transformation parameterized with a secret
key. That is, it is an implementation of MAC (M K). In this
paper, we treat a standardized HMAC, The security of such
implementations has been revised, stating that the attacks “do
not contradict the security proof of HMAC, but they improve
our understanding of the security of HMAC based on the
existing cryptographic hash functions.
I.
RESULTS AND D ISCUSSIONS
In this chapter the simulation results of the Data
aggregation and authentication protocol are discussed.
A Testing Results of DAA Protocol Software
Testing is a critical element which assures effectiveness of
the proposed system in meeting its objectives. Testing is done
at various stages in the System designing and implementation
process with an objective of developing a transparent, flexible
and secured system. The purpose of testing is to discover
errors. Testing is the process of trying to discover every
conceivable fault or weakness in a work product. It provides a
way to check the functionality of components, sub assemblies,
assemblies and/or a finished product. It is the process of
exercising software with the intent of ensuring that the
software meets its requirements and user expectations and
does not fail in an unacceptable manner.
WLANs have revolutionized the way people are using their
computers to communicate. As WLANs eliminate the need of
wires for connecting end users, they provide a very easy,
viable access to the network and its services. A wireless LAN
or WLAN is a wireless local area network, which is the
linking of two or more computers without using wires.
WLAN utilizes spread-spectrum modulation technology
based on radio waves to enable communication between
devices in a limited area, also known as the basic service set.
This gives users the mobility to move around within a broad
coverage area and still be connected to the network. Wireless
has become popular due to ease of installation and mobility.
To transport the data on a wireless network radio frequency,
microwave and infrared are used as a transportation media.
After establishing the WLAN network connection between
server and the clients, clients can request for any files or data
from the server.
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International Journal of Engineering Trends and Technology (IJETT) – Volume 4 Issue 10-Oct 2013
B Simulation Results for Secure Data Transmission
Run the Server and Client source code programs. After
running the Server and Client source code programs, we can
observe the Client home window and Server home window as
shown in Fig. 3 and Fig. 4 respectively.
Fig. 4 shows the client design snap snapshot. In this figure
we can observe the following blocks:
 Select receiving path
 Received Key Value
 Generate key and
 Validate
1) Client (computer): A client is an application or system that
accesses a remote service on another computer system, known
as a server, by way of a network. The term was first applied to
devices that were not capable of running their own standalone programs, but could interact with remote computers via
a network (WLAN). These dumb terminals were clients of the
time-sharing mainframe computer.
 Server
 Generate key
 Connect to client
Fig. 4 Snapshot of Server Home Window
5) Server: A computer program running as a service, to serve
the needs or requests of other programs (referred to in this
context as "clients") which may or may not be running on the
same computer. In computer networking, a server is a
program that operates as a socket listener. The term server is
also often generalized to describe a host that is deployed to
execute one or more such programs.
Fig. 3 Snapshot of Client Home Window
2) Select receiving path: To access a remote service from
another computer (Server), client has to choose the receiving
path. Client can select any drive or folder as the receiving path
to save the received file or data.
3) Generate Key: Before transmitting the actual file server
computes the key value and encrypts the file. Encrypted file is
transferred over the network to the destination. During data
forwarding between every two consecutive data aggregators,
the aggregated data are encrypted at data aggregators and false
data detection is performed over the encrypted data rather than
the plain data. Whenever the verification of encrypted data
fails at a forwarding node, the data are dropped immediately.
Client receives the transmitted file as well as generated key at
the server. To verify the received data client has to recompute
the key value for the received file. Therefore the main
function of the Generate key icon at the client is to generate
key value for the received file.
4) Validate: To verify the correctness of the received file, it is
necessary to compare the generated key value at the receiver
(client) side and received key value. Click on the validate icon
on the client window it compares the generated key with the
received key, if they are equal then it displays “successfully
received full data” , otherwise it displays a warning message
“founded file has been corrupted”.
Fig. 4 shows the client design snap snapshot. In this figure
we can observe the following blocks:
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Fig. 5 Snapshot for File Selection
A server computer is a computer, or series of computers,
that link other computers or electronic devices together. They
often provide essential services across a network, either to
private users inside a large organization or to public users via
the internet. For example, when user enters a query in a search
engine, the query is sent from your computer over the internet
to the servers that store all the relevant web pages. The results
are sent back by the server to user computer.
At the Server it is necessary to select a file for transmission.
To select a file from the server click on the Open button on
the server home window then it shows a list of documents as
shown in Fig. 5. In Fig. 5 it is observed that SAMPLE
SCREEN.doc file is selected for transmission. Next step is to
encrypt the file and generate a pseudorandom key value.
6) Generate Key: Before transmitting the actual file server
computes the key value as shown in Fig. 5 . We can see that
the generated key value is 2591193488. Server transmits
generated key as well as the encrypted file via WLAN.
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International Journal of Engineering Trends and Technology (IJETT) – Volume 4 Issue 10-Oct 2013
receiving path and generated key 2591193488. Client again
recomputed the key value for the received data and is same as
that of the received key value 2591193488. Therefore it
indicates the successful reception of the full data. It also
shows the message “No False Data, Received successfully”.
Fig. 6 Snapshot for Generated Key Value at the Server
7) Connect to client: It shows the list of client IP addresses
that are connected to the server as shown in Fig. 7. We can see
there are two clients are connected to the server with IP
address 192.168.1.3 and 192.168.1.4. From the list of client
IP’s, we must select any one client IP as destination address.
We can observe the transmitted IP is 192.168.1.4.
Fig. 9 Snapshot of Client Home Window for Successful Reception of the Data
Fig. 10 Snapshot of Average Received Data V/S Key Value
Fig. 7 Snapshot of Client List Window
In Fig. 8 we can observe the selected destination IP
address 192.168.1.4 and server transfers the encrypted file to
this IP address. By transmitting encrypted data rather than the
plain data DAA protocol provides confidentiality. Encrypted
data is aggregated at each of the sensor node (client). In this
protocol aggregation is a technique used to solve the
Implosion and Overlaying problems in WSN. Implosion
means reception of the multiple copies of the same file and
overlaying means reception of the multiple files with same
name. The proposed protocol eliminates these two problems
by aggregating the sensor data at each node. The aggregated
data are encrypted at data aggregators and false data detection
is performed over the encrypted data rather than the plain data.
Whenever the verification of encrypted data fails at a
forwarding node, the data are dropped immediately to
minimize the waste of resources such as bandwidth and
battery power due to false data injection.
Fig. 11 shows the snapshot of the graph of average received
data and the key value. It clearly shows that both key values
are same. Therefore no false data is injected to the transmitted
data.
C Simulation Results for Data Aggregation and False Data
Detection
As we know that data aggregation eliminates the implosion
and overlaying problems in Wireless sensor networks. To
illustrate this in simulation consider the same file transmission
to the same destination IP address, which already contains a
copy of this file. From Fig. 11, we can observe that the
received key value is 2591193488 but the generated key value
is 2257643084. Therefore Data aggregation and authentication
protocol eliminates the implosion and overlaying problems. It
detects that the received file has been corrupted and it shows
the message box “Error: False data received”.
Fig. 8 Snapshot showing Destination IP Address
Saturday, June 02, 2012
Fig. 11 Snapshot of False Data Detection
Fig. 9 shows the reception of the correct data. We
can observe the client is receiving transmitted data to
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International Journal of Engineering Trends and Technology (IJETT) – Volume 4 Issue 10-Oct 2013
MTIET, Palamaner and the Staff members of ECE Dept.
MTIET, family members, and friends, one and all who helped
us to make this paper successful.
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Fig. 12 snapshot of graph of Average received data and Key Value
Fig. 12 shows the snapshot of the graph of average
received data and key value. It clearly shows that both key
values are different. Therefore it indicates founded file has
been corrupted and Error: False data reception. Therefore
Data aggregation and authentication protocol integrates data
aggregation, confidentiality and false data detection. It also
reduces the amount of data transmitted over the Wireless
sensor network with the help of data aggregation and early
detection of false data.
II.
CONCLUSION
In wireless sensor networks, compromised sensor nodes
can distort the integrity of data by injecting false data.
Previously known techniques on false data detection do not
support data confidentiality and aggregation, even though they
are usually essential to wireless sensor networks. However,
this Work has presented the novel security protocol DAA to
integrate data aggregation, confidentiality, and false data
detection. DAA appends two FMACs to each data packet.
To reduce the communication overhead of algorithm SDFC,
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sensor nodes. The performance analysis indicates that the
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The proposed protocol also provides data confidentiality as
data are forwarded between data aggregators. To provide data
confidentiality during data forwarding between every two
consecutive data aggregators, the aggregated data are
encrypted at data aggregators, and false data detection is
performed over the encrypted data rather than the plain data.
Whenever the verification of encrypted data fails at a
forwarding node, the data are dropped immediately to
minimize the waste of resources such as bandwidth and
battery power due to false data injection.
The simulation result shows that the amount of transmitted
data over the wireless sensor network is reduced with the help
of data aggregation and early detection of false data.
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MTIET, Palamaner, Chittoor, Principal MTIET, Management
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