International Journal of Computer Trends and Technology ( IJCTT ) – Volume 64 Number 1 – October 2018 Wave File Encryption using Huffman Compression and Serpent Algorithm Parasian D.P Silitonga#1, Imka Ardianta Singarimbun*2, Irene Sri Morina#3 #Faculty Of Computer Science & St. Thomas Catholic University Setia Budi Medan, Indonesia Abstract Serpent is a block cipher algorithm that has a Wave file (.wav) is a standard audio file used block size of 128 bits and supports key sizes of 128, by Windows. Sound recording files (* .wav) tend to 192, or 256 bits [7]. This cipher is in the form of a have a large size, according to the length of time Subtitution-Permutation Network (SP-network) sound recording. Large files can cause various which is a series of mathematical operations that are problems in the form of large space requirements for related slings. SP-networks have S-boxes that convert listening and a long time in the shipping process. File the input bit blocks into an output bit. compression is one solution that can be done to overcome large file size problems. One method of file II. LITERATURE REVIEW compression is to use the Huffman compression A. Wave File method. In addition to problems in space and length of delivery time in the file processing process, data Wave file (.wav) is a standard audio file used by security factors are also a problem that continues to Windows [1]. Wave files allow various audio forms this day. The Serpent algorithm is one of the data to be recorded in various qualities, such as 8-bit or cryptography algorithms that can be used to maintain 16-bit samples with a rate of 11025 Hz, 22050 Hz or data confidentiality. Serpent is a block cipher 44100 Hz [12]. algorithm that has a block size of 128 bits and Wave files are widely used in game making. supports key sizes of 128, 192, or 256 bits. The results Usually for sound effects and music. Wave itself obtained in this study are the Huffman compression tends to have a large size, but this is because the wave ratio and the implementation of the Serpent algorithm file format is uncompressed so it has a faster loading performed on wave files. time. Digital audio data in wave files can have varying qualities. The quality of the resulting sound is Keywords —Wave File, File Compression, Huffman determined by the bitrate, samplerate, and number of Method, Criptography, Serpent Algorithm channels [6]. Bitrate is the bit size of each sample, which is 8 I. INTRODUCTION bits, 16 bits, 24 bits or 32 bits [3]. In 8-bits wav all Wave file (.wav) is a standard audio file used by the samples will only take as much as 1 byte. windows [1]. Sounds in wave form are stored in Whereas for 16-bits it will take 2 bytes. digital audio data format in * .wav files. Sound While samplerate states the number of samples recording files (* .wav) tend to have a large size, played every second. Samplerate commonly used is according to the length of time sound recording. 8000 Hz, 1105 Hz, 22050 Hz, and 44100 Hz [3]. In the process of storing and sending data, large While the number of channels determines the sound files have constraints that require large space to store produced whether mono or stereo [3]. Mono has only and require a long time to send. To overcome this, file 1 channel, while stereo 2 channels will take up to 2 compression can be done. Compression is the process times more space than mono. of encoding information using fewer bits than the B. File Compression initial information [10]. There are two types of Data compression is done to reduce the size of compresses, namely lossless and lossy [17]. data or files. By compressing or compressing data, the Huffman compression is a lossless compression file or data size will be smaller so that it can reduce algorithm and is ideal for compressing text or transmission time when data is sent and not spend program files [16]. Huffman compression is included much storage media space [18]. in the variable codeword length algorithm [14]. In Compression is the process of encoding this algorithm the individual symbols are replaced by information using fewer bits than the initial bit sequences which have a distinct length [13]. information [10]. There are two types of compresses, Cryptography is a technique used to guarantee the namely lossless and lossy [17]. n lossless security aspects of data exchange such as data compression, the data will initially be broken down confidentiality, data correctness, data integrity, and into smaller sizes and finally the data is reassembled. data authentication [9]. There are various kinds of Whereas, in lossy compression, there are bits of encryption algorithms with their respective characteristics, one of which is the Serpent algorithm. ISSN: 2231 – 2803 http://www.ijcttjournal.org Page 24 International Journal of Computer Trends and Technology ( IJCTT ) – Volume 64 Number 1 – October 2018 information which are eliminated after being done for The Serpent algorithm uses twice as many rounds compression [10]. as needed to block all the shortcut attacks that are The general principle in the compression process currently happening. This means that the Serpent is to reduce duplication of data so that the memory must be safe against as unknown attacks that might be represents less than representing the original digital able to break 16 standard rounds used in various types data [17]. of encryption at this time. However, the fact that Serpent uses so many rounds. C. Huffman Method Serpent is a cipher block algorithm that has a The Huffman compression algorithm is named block size of 128 bits and supports key sizes of 128, after its inventor, David Huffman, a professor at MIT 192, or 256 bits [7]. This cipher is in the form of a (Massachusetts Institute of Technology. Huffman Subtitution-Permutation Network (SP-network) compression is a lossless compression algorithm and which is a series of mathematical operations that are is ideal for compressing text or program files [16]. related slings. SP-networks have S-boxes that convert This causes why this algorithm is widely used in the input bit blocks into an output bit. compression programs. Huffman compression is included in the variable III. METHODOLOGY codeword length algorithm [14]. In this algorithm the In this study the wave file was obtained through individual symbols are replaced by bit sequences two sources, namely microphone and audio file. To which have a distinct length [13]. Symbols that process input from the microphone, a digitalisation appear quite a lot in the file will give a short sequence mechanism is needed. Then the compression process while symbols that are rarely used will have a longer is done to reduce the size to be entered into the sequence of bits. The way the Huffman method works encryption process. is by encoding the bits (a combination of bits 0 and 1) The serpent algorithm is used to encrypt the voice to represent the actual data [2]. message flow by changing the operating mode that is used until the characteristics resemble the flow cipher, D. Criptography that is, the counter operation mode. Cryptography is a technique used to guarantee the security aspects of data exchange such as data A. Huffman Compression on Wave File confidentiality, data correctness, data integrity, and The way the Huffman method works is to encode data authentication [9]. To ensure the security of data the bit (a combination of bits 0 and 1) to represent the exchange, it can be done in various ways, one of actual data. The compression steps with the Huffman which is by encoding the password algorithm. method are as follows [16] : The encoding process is carried out so that the 1) Calculate the frequency or weight of the data sent cannot be understood by anyone other than appearance of each character in a file. those who have access to the data [Rinaldi Munir]. In Wave files use a standard RIFF structure that the encoding process there are two main concepts, groups file contents into separate chunks [3]. Each namely encryption and decryption. section has its own header and data byte. Encryption is the process of changing data or Here is a wave file where the first 60 bytes of a information that will be sent into a form that is almost wave file are displayed in hexadecimal : unrecognized as the initial information [5]. Encryption is usually done before the data or 52 49 46 46 24 08 00 00 57 41 56 45 information is sent. 66 6D 74 20 10 00 00 00 01 00 02 00 In cryptography process, data or information that is 22 56 00 00 88 58 01 00 04 00 10 00 understandable means that it is known as plain text or 64 61 74 61 00 08 00 00 00 00 cA 00 clear text while the information that has been 00 00 CA 0F 00 00 CA F0 00 00 CA FF obscured is known as a text cipher [4]. To improve the security of information encryption, the key is To form a Huffman frequency table, a 16 byte added to the encryption process. Whereas decryption data wave file is taken starting from the 45th byte is the process of converting ciphertext into plain text. offset, which is data: E. Serpent Algortihm 00 00 CA 00 00 00 CA 0F 00 00 CA F0 Serpent was designed by Ross Anderson, Eli 00 00 CA FF Biham and Lars Knudsen [11]. The Serpent algorithm is faster than DES and is safer than Triple DES [8].