The algorithms yield an encryption mechanism and an encryption key which can be made public and a decryption algorithm and decryption key that is kept secret. The mathematics of the algorithms is so complex that it is not possible to deduce the decryption mechanism from the encryption mechanism alone.
The ePSA codes are a set of information which guides the user about the errors within the computer system. There are several errors which can occur; moreover it is quite hard to tackle these errors. The ePSA error code is basically a number, which contains the information about the error. Different error codes have different explanation and solutions. If you are unaware of the ePSA error codes, or if you have not encountered one yet, then it is advisable to look into the Dell tech support phone number.