Cryptography and Authentication Lab ECE4112 Group4 Joel Davis Scott Allen Quinn

Outline Introduction Cryptography Basics Sample of Cryptography Protocols Authentication Basics Authentication Methods Lab Walkthrough

Introduction Cryptography is the method of message secrecy Cryptography has been applied since the early day of computers for military and other types of data security With the spread of the Internet and the ease of data acquisition cryptography has become more important and more widely used.

Cryptography Basics Key- A key is a piece of information that controls the algorithm in cryptographic cipher. Weak Key- A Weak Key is a key that when inputted into an encryption algorithm makes the algorithm act in an undesired way (i.e. easily crack able). Asymmetric Key Cryptography- Asymmetric key cryptography is encryption methods in which two distinct keys are used. Symmetric Key Cryptography- Symmetric algorithms are ones in which the keys for encrypting and decrypting the data are the same or very closely related. Block Cipher- A block cipher is a symmetric key encryption in which the operations are performed on fixed lengths of bits called blocks. Stream Cipher- A stream cipher is a cipher in which each plaintext character is encrypted one at a time with the transformations varying for each successive character.

Samples of Cryptography Protocols AES (Advanced Encryption Standard) - AES is a block encryption standard that superseded DES. It is a 128bit encryption standard that is used by the U.S. government and widely used by other systems including WPA2 and SSH. Diffie-Hellman- The Diffie-Hellman key exchange protocol is a protocol that allows to parties to setup a shared secure key without prior knowledge of either group. IPSEC- IPSEC is a suite of protocols that help authenticate, setup public keys, and encrypt streams of IP traffic. MD5- Not considered secure anymore, MD5 is a widely used hash algorithm that is also often used for file integrity checking. RC4- Is one of the most widely used stream ciphers. It is used by both SSL and WEP to encrypt data. SSH (Secure Shell) – SSH is a public key algorithm used to authenticate and secure connections between systems.

Samples of Cryptography Protocols WEP (Wired Equivalent Privacy) – WEP is part of the standard that tries to protect the wireless signal from eavesdropping. Soon after implementation its security was breached due to its use of the RC4 cipher. WPA (Wi-Fi Protected Access) – WPA was an intermediate step in the creation of i. Because of the security risk the WPA standard was rolled out while the i standard was being finalized. WPA2 (802.11i) – WPA2 is the full implementation of the i protocol. WPA2 uses the AES block cipher algorithm instead of the RC4 stream cipher that is used in the WEP and WPA.

Authentication Basics Provides trust on networks Describes identity and data security Transactions require one-side or two- sided authentication Accountability is provided by Certificate Authorities and governments

Certificates Used to sign items Issued by certificate authorities Trusted third parties Certificate can be trusted as long as CA is not compromised

Digital Signatures Provides authentication for documents and communication S/MIME used for communication Secure XML specifications provide XML formatted documents with security.

Windows CardSpace Microsoft developed framework for ID Set of ID cards in the CardSpace provides necessary claims Secure data is not actually stored on your computer Novel idea, but it may not be used widely

Directory Services Provide a central database for network user’s information One set of credentials for the entire network Easier for administration Standard set of protocols for accessing the information Kerberos LDAP

Lab Layout Prelab Go to the NSA’s CryptoKids website and learn some basic encryption techniques to gain experience with basic cryptography. Section 1 Small database of common cryptography terms and methods Section 2 Gets some hands on experience with a handful of programs that encrypt and decrypt data with the methods described in section 1.

Lab Layout Section 3 Authentication basics, defining certificates, signing, Windows CardSpace, and directory services. Section 4 Use an certificate to sign and encrypt communication Create a Windows CardSpace card and test it

References us/netframework/aa aspx us/netframework/aa aspx certificate.html certificate.html