IT | "Internet of Things" & Security Techniques: An Overview

IT | "Internet of Things" & Security Techniques: An Overview

By Lobna Yehia, Ayman Khedr and Ashraf Darwish
Helwan University, Cairo, Egypt
 
IT | "Internet of Things" & Security Techniques: An Overview
 
In the future, everything will be connected to the web; mobile phones will serve as the remote control, or the hub, for all the things in our physical world which is broadly termed as "Internet of Things" (IoT). IoT is an integrated part of future Internet and could be defined as a dynamic global network infrastructure with self-configuring capabilities based on standard and interoperable communication protocols where physical and virtual “things” have identities, physical attributes, and virtual personalities and use intelligent interfaces, and are seamlessly integrated into the information network.
 
In this network, the mobile phone will help you coordinate the interactions of the things around you and provide real-time access to all types of information, including the people you meet, the places you go and the content that’s available there. Some research estimates that the number of connected objects will reach 50 billion by 2020. The IoT promises humans to provide a smart life, highly networked world, which allows for a wide range of interactions with this environment. Techniques for interacting with wireless sensors such as IoT and sensor cloud aim to overcome restricted resources and efficiency. The data captured by a set of sensors can be collected, processed according to an application-provided aggregation function, and then perceived as the reading of a single virtual sensor. This data should be protected and secured.

Some of the common security techniques that are used in the protection and immunization databases and in IoT:

 
1) Access Control: Access control is a security technique which restricts the access to the data on database and its information except for the authorized users.

There are two main types of access control:

a) Physical access control limits access to rooms, buildings and physical IT assets.

b) Logical access control limits connections to data, system files and computer networks.

 
2) Hashing: Hashing is used to index and retrieve items in a database by using hash functions and can be defined as the transformation of a string of characters into a usually shorter fixed-length value or key that represents the original string.

 
3) Steganography: Steganography is process of hiding/encrypt sensitive information in any type of media.

4) Cryptography: Cryptography is the practice and study of techniques for secure communication in which the ordinary text is converted to cipher text by encryption.

5) Hybrid Cryptography: Hybrid cryptography is a technique using multiple ciphers of different types together (symmetric and asymmetric ciphers), to take benefit of the strengths of each type of cryptography.

 
One common approach is to generate a random secret key for a symmetric cipher, and then encrypt this key via an asymmetric cipher using the recipient’s public key. The message itself is then encrypted using the symmetric cipher and the secret key. Both the encrypted secret key and the encrypted message are then sent to the recipient. The recipient decrypts the secret key first, using his/her own private key, and then uses that key to decrypt the message. Most security systems use cryptography because it offers various algorithms and techniques practically impossible to break because of their complexity. There are three main types of cryptographic algorithms: symmetric (or secret key) cryptography, asymmetric (or public-key) cryptography, and hash functions.
1. Secret Key (Symmetric) Cryptography (SKC)
This type of cryptography uses the same (only one) key for both encryption and decryption, and it is called also secret cryptography (SKC) and it works as the following:

 
The plaintext is encrypted with the key and the cipher text is sent to the receiver who uses the same key to decrypt the cipher text and recover the plaintext.

 
Both the sender and receiver must know the key to use this technique.

 
Stream chipper and block chipper are the most popular secret key cryptography schemes. The stream ciphers generate a sequence of bits used as a key called a key stream and by combining the key stream with the plaintext, the encryption is achieved. A block cipher transforms a fixed-length block of plaintext into a block of cipher text of the same length. By applying the reverse transformation of the cipher text block, the same secret key is used for the decryption.

2. Public-Key (Asymmetric) Cryptography (PKC)

This type of cryptography requires two kinds of keys. One to encrypt the plaintext and other one to decrypt the cipher text. It is called asymmetric cryptography because it is used a pair of keys: one is the public key that can be advertised by the owner to anyone who wants, and the other one is the private key and it is known only by the owner. Public key cryptography algorithms that are in use today for key exchange, digital signatures, or encryption of small blocks of data is RSA algorithm. It uses a variable size encryption block and a variable size key. The reason for the RSA algorithm’s security is that the factorization of very large numbers. Two prime numbers are generated by a special set of rules, and the product of these numbers is a very large number, from which it derives the key-set.

3. Hash Functions

A hash function creates a fixed size blocks of data by using entry data with variable length. It is called also message digest or one-way encryption. If the data is modified after the hash function was generated, the second value of the hash function of the data will be different. The smallest alteration of the data like adding a comma into a text, will create huge differences between the hash values. The hash values solve the problem of the integrity of the messages. The most common hash algorithms use today is Message Digest (MD) and Secure Hash Algorithm (SHA) for computing a finger print of a data file. SHA-1 produces a 160-bit (20 byte) message digest. Although it is slower than MD5, it stronger against brute force attack, it has a larger digest size. The advantage of MD5 is that it can be implemented faster, due to its 128 bit (16 byte) message digest
 

By these cryptography techniques, we propose a hybrid approach which combines them for collecting benefits from all of their strengths and tries to reduce as much as possible the weakness of one with the advantages of the other, briefly as the following:
 
The original message’s message digest is digitally signed (the digital signature uses RSA algorithm).

 
Symmetric cipher is used to code the original message. The secret key is obtained using a key generator and it is changed periodic-time.

 
The private key used for symmetric cipher is coded using also RSA algorithm, but with different keys.

 
The coded private key is attached to the encrypted message together with the digital signature.

 
The combination of different cryptography algorithms provide a maximized efficiency, correcting or compensating each other’s weaknesses. It can be applied to health care applications mentioned below and their own data.

 
IoT as a new technology has been more widely used. There are many related applications which depends on one of the most important technologies such as wireless sensor networks that can be used for connecting the physical world with the logic information world. The open nature of the information/data media has brought risks to the security of the wireless sensor networks and their collected data. In this paper, authors surveyed and discussed some of the security techniques for various application that can be applied in IoT environment issue, and introduced some of security techniques that are used in data security and immunization.

About The Authors:

Lobna Yehia - Computer Science Department, Faculty of Science, Helwan University, Cairo, Egypt

Ayman Khedr - Information Systems Department, Faculty of Computers & Information, Helwan University, Cairo, Egypt.

Ashraf Darwish - Computer Science Department, Faculty of Science, Helwan University, Cairo, Egypt

Publication Details:

This article is an excerpt from a technical paper Hybrid Security Techniques for Internet of Things Healthcare Applications / Advances in Internet of Things Vol.05 No.03(2015), Article ID:60067,4 pages 10.4236/ait.2015.53004

Copyright © 2015 by authors and Scientific Research Publishing Inc.
This work is licensed under the Creative Commons Attribution International License (CC BY).
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