An authentication mechanism in which a Web application authenticates itself to a Web server by sending the server a message

digest along with its HTTP request message. The digest is computed by employing a one-way hash algorithm to a concatenation

of the HTTP request message and the client's password. The digest is typically much smaller than the HTTP request and doesn't

contain the password.

1) Method for checking the integrity of transmitted data. A checksum is an integer value computed from a sequence of octets taken through a series of arithmetic operations. The value is recomputed at the receiving end and compared for verification. 2) Calculated checksum of the header and data fields.

Aggregate tables are pre-computed totals in the form of hierarchical mutidimensional structure.,whereas materliazed view is the database object which caches the query result in a concrete table and updates it from the original database table from time to time .Aggregate tables are used to speed up the query computing whereas materialized view speed up the data retrieval .

Radiofrequency Ablation is a special needle electrode is placed in the tumor under the guidance of an imaging method such as ultrasound or computed tomography (CT) scanning. A radiofrequency current then is passed through the electrode to heat the tumor tissue near the needle tip and ablate-or eliminate-it. The heat from radiofrequency energy also closes up small blood vessels, thereby minimizing the risk of bleeding. In general, radiofrequency ablation causes only minimal discomfort and may be done as an outpatient procedure without general anesthesia. Admission to the hospital is not usually necessary.