System Analysis and Design Paper 57

EDI standard

Proxy application gateway
i. acts on behalf of all intranet users wanting to access internet securely
ii. monitors all accesses to internet and allows access to only specified IP addresses
iii. disallows use of certain protocols with security problems
iv. disallows all internet users from accessing intranet

The following ciphertext was received. The plaintext was permuted using permutation (34152) and substitution. Substitute character by character ±3 (A → D, etc). The plain text after decryption is: Cipher text : PDLJDLXHVQC

Triple DES uses

A digital signature is required
i. to tie an electronic message to the sender identity
ii. for non repudiation of communication by a sender
iii. to prove that a message was sent by the sender in a court of law
iv. in all e-mail transactions

In electronic cheque payments developed, it is assumed that most of the transactions will be

EDI standards are

EDI over internet uses

Main function of proxy application gateway firewall is

In cheque payment protocol, the purchase order form is signed by purchaser using