The paper presents a brief overview of Online BankTransaction Processing system which addresses entireprocess of online trading starting from the basicTerminologies to functionality offered by each components &then heading towards actual work flow. As we all know howmuch secured and confidential bank account details are thanwhat actually makes it possible for middleware’s like Flipkart,Paytm, Snapdeal to look into clients account and smoothlycarry out transaction process, by deducting the exact paymentand that too without causing any security issues. The paymentGateway is responsible for offering n number of features suchas customer & merchants account authentication,unforgivable proof by customer to merchant & bank. Mostimportantly personal credentials of user are highly secured. The security architecture of the system isdesigned by using Security Protocols Techniques such asSecured Socket Layer, Secured Electronic Transactionprotocol, Tunneling protocol and Encryption standard whichinclude 56bit DES (Data Encryption System), 168bit TDES(Triple Data Encryption System), and AES (AdvanceEncryption Technique).