This paper presents two level data security in Network system. Cryptographic algorithm BLOWFISH and Steganography algorithm List significant Bit (LSB) are used for data security. Confidential information is encrypted by BLOWFISH algorithm, and then encrypted data hide into image by LSB algorithm of Steganography. For more security is used iris image of authorized person to hide encrypted data. The keys required for BLOWFISH algorithm is generated from same iris image. These two algorithms implemented on 32 bit ARM 7. In the result of project include memory utilization, processing time for encryption and decryption etc. this project gives better security for embedded systems like mobile, smart card, ATM etc.
 Johnson, Neil F. And Sushil Jajodia. “Exploring steganography: seeing the unseen.” IEEE computer, 32:2. 26-34. 1998.  Proves, N. And Honeyman, P. “Hide and Seek: An Introduction to steganography.” IEEE security &privacy, (2003). William Stallings, ―Cryptography and Network Security: Principles and Practice‖, 4th Edition, Prentice Hall, 2006. Alex Salkever, Open-Source Security Is Opening Eyes, BusinessWeek Online, and 19 November 2002: Andrew Conry-Murray, Kerberos: Computer Security’s Hellhound, Network Magazine, 5 July 2001:  Menezes, A., Van Oorschot, P., and Vanstone, S. “Handbook of applied cryptography.” CRC Press, (1996).  Hassan Mathkour, Batool AL-sadoon, ameur touir ” a new image steganography technique”.  Sim hiew moi, nazeema binti abdul rahim,puteh saad, pang li sim, zalmiyah zakaria, subariah ibrahim, “iris biometric cryptography for identity document”, 2009 international conference of soft computing and pattern recognition.  Sujay narayana1and gaurav prasad” two new approaches for secured image steganography using cryptographic techniques and type conversions” signal & image processing: an international journal (sipij) vol.1, no.2, December 2010.  Mamta juneja 1, parvinder singh sandhu2 “designing of robust image steganography technique based on lsb insertion and encryption” 2009 international conference on advances in recent technologies in communication and computing.
Network Security, Blowfish, Cryptography, Embedded System, List Significant Bit, Steganography