Security proofs of cryptographic protocols

We live in time of computers and scientific and technological progress but this time is also marked with many attacks on big Internet companies. So with expand of Internet people start to protect information that they exchange through Internet. In the Internet world it is necessary for systems as Internet banking, Internet shopping or e-commerce to secure private information that are transferred via Internet. This necessity leads to design security improvements of existing protocols and to design and implement cryptographic algorithms (for example protocols as L2TP, Microsoft PPTP, IPSec, SSH or algorithms as DES, Blowfish and others). Consider that we have two banks, bank “ Alice” and bank “ Bob” and these two banks for business purposes need the private cipher for their communication. They need this cipher to do secret bank operation. So they need the secure way, how to arrange the cipher. For this purpose the designers designed the communication protocols. But the both banks “ Alice” and “ Bob” must be sure that no one can achieve this cipher by negotiation and both must be sure that they talk with the cipher one with the other. And such proofs about communicating protocols can be done only with the security analysis. So it is not enough to design any “ security” protocol or cryptographic algorithm, more important is to prove that protocol is really secure. In the world of informaticians and designers it must be developed new methods and formalisms that give us exact proofs of correctness and soundness of security protocols and cryptographic algorithms.