IBM Corp. is getting ready to announce a system of encryption that will, reportedly, simultaneously encrypt and digitally sign data. The benefit of this system, the company says, is that it will reduce the time it takes to transmit large, secure documents by half. Critics, however, say that it will take years to be sure the new algorithm is truly secure and that encryption is not the slowest link in the Internet chain. Moreover, faster chips and networks will provide speed improvements without implementing uninvestigated encryption schemes. Criticism is probably more pointed as IBM announced, two years ago, that its "Cramer-Shoup cryptosystem" would replace for Secure Sockets Layer (SSL), the protocol that still protects e-commerce transactions.