Table of Contents.
Added on - 21 Sep 2019
Table of ContentsPart 3: Cryptography security Assessment2Bibliography6
PUBLIC KEY INFRASTRUCTURERequirements:The growth of internet helps the business people to communicate easily. The communicationtakes place through the public data network. The data transmitted should be checked for security.To secure the data communication PKI (public key infrastructure) is used. Consider a data istransmitted using internet tools such as WWW or email, the content of the data should besecured. So the confidentiality of the data should be maintained. The data should beauthenticated only by the authorized person. The content of the data should be secured withoutany changes being done by the third party member. So Integrity of the data should bemaintained. This process of securing the message between the third party members by using theencryption techniques using the key is said to be Public Key Infrastructure.Purpose:In PKI, two different keys are used. They are public key and the private key. The private key iskept secret and the public key is shared between the users. Hence this type of techniques isasymmetric cryptographic techniques. If a message is encrypted with the public key it isdecrypted only with the private key. Likewise if a message is encrypted with the private key it isdecrypted only with the public key. Suppose if a person A wants to send a encrypted message toperson B the message is send along with the public key so that the person B can decrypt themessage using the private key of B. This type of security mechanism is followed in PKI.Justification:Since the Key pair mechanism is used in this infrastructure there will not be any confidentialityissues key distribution. Only two keys are used to avoid ambiguity. It is very easy foradministration. This method uses mechanisms like digital signature algorithm and El - Gamalusing digital signature method. Key exchange algorithm such as Diffie – Hellman and RSA isused for encryption and decryption method.SECURITY PROTOCOLRequirements:The need for securing the information which is communicated via internet is increased.Automatic tools are used for protecting the information. During the data communication trafficoccurs between the networks. So it must be secured by using SSL (Secured Socket Layer) orVPN (Virtual private network). The aspect of security is to protect from the attack. The attackmay be active or passive attack. Passive attack is trying to access the information from thesystem without affecting any resources of the system. Active attack is trying to access the system
information which affects the resources of the system. Other types of security threats areinterruption, interception, modification and fabrication.Purpose:SSL provides a secure end to end communication. It uses digital signature to authenticate theinformation to make the data communication confidential. This protocol supports the variety ofcryptographic techniques such as DES, SHA, DSA, RSA, etc. It uses same key for encryptionand decryption. The secret key is also known as session key. PGP (Pretty Good Privacy) is usedfor encrypting the email using the session key encryption. This encryption method can be donefor large volume of data.Justification:Cryptographic protocols are defined to secure the communication using single key encryptiontechniques. Freshness mechanism such as Timestamps and nonce and Time based mechanism isused to secure the communication without any data loss and data correction.FILE ENCRYPTIONRequirements:The main requirement for securing the information is secrecy, authentication and messageintegrity. The message which is sent should be encrypted. Cipher is a method used forencryption. The original message should be hidden by using other text. This method is calledencryption. Symmetric key and Asymmetric key is used for encryption. Symmetric key is usingthe same key for both encryption and decryption. Asymmetric key is using the different key forboth encryption and decryption. For different scenario different encryption algorithms are used.Purpose:Symmetric algorithm uses Block cipher and steam cipher. Data encryption done by block of dataat a time is Block cipher. Data encryption done be bit by bit is Steam cipher. Each mechanismuse separate method for encrypting the data. Each encryption standard is determined by thenumber of encryption keys. Substitution cipher such as caesar cipher, monoalphabetic cipher,polyalphabetic cipher and Transposition Cipher such as columnar techniques and Rail fencetechnique is used for encryption. Each technique has unique method for encryption of data.Justification:File encryption is used for securing the data with the basic security principles such asconfidentiality, integrity and availability. The data should be read only by the authorized users byprotecting it with the encryption techniques. The data in the file should not be altered by third