CAS Registry BLAST logo

Security of CAS Registry BLAST Queries and Results

CAS recognizes that the sequence queries that are submitted for BLAST® searching and the BLAST search results are valuable intellectual property. To safeguard this information, the sequence search process has been designed to encrypt this information before transmitting it across the network.

The CAS Registry BLAST application uses the industry-standard Secure Sockets Layer (SSL) protocol with 128-bit encryption to encrypt BLAST queries before they leave the customer PC and to decrypt them after they reach a server at CAS. The SSL also encrypts BLAST search results before they leave the CAS server and decrypts them after they reach the customer PC.

128-bit SSL is cryptographically secure. There is no way for anyone to intercept or capture this information in any usable manner.

It is used for financial transactions and other applications requiring a high level of security.

Technical Details

The SSL protocol uses public key encryption technology. With this technology, each party in an encrypted exchange has two related encryption keys:

A message encrypted with a public encryption key can only be decrypted with the associated private encryption key. Thus, anyone can encrypt a message with a given public encryption key, but only the owner of that key can decrypt the message because only the owner has the associated private encryption key.

The SSL protocol begins by verifying the identity of the server at CAS. This verification requires several steps:

The SSL protocol then continues encrypting messages exchanged between the client and the server. The key used to encrypt messages is based on the master encryption key, but changes with each message exchange using a random number generator. Thus, the effort used to break the encryption on one message would not help with decrypting the next.

The CAS Registry BLAST application uses encryption keys that are 128 bits long. As a measure of the security provided by this level of encryption, on average, a computer with 64 MIPS (Millions of Instructions per Second) of processing power would require one year to break the encryption of a message when 40-bit encryption is used. 128-bit encryption is 3.0 x 1026 more powerful than 40-bit encryption.


GenBank® is a registered trademark of the U.S. Department of Health and Human Services for the Genetic Sequence Data Bank.

BLAST® is a registered trademark of the National Library of Medicine.

BLAST® reference information provided in whole or in part from the National Center for Biotechnology Information (NCBI), National Library of Medicine, National Institutes of Health.

Unless designated otherwise, all other information Copyright © 1997-2017 by the American Chemical Society. All rights reserved.