Link Encryption

Link encryption is an approach to communications security that encrypts and decrypts all traffic at each end of a communications line (e.g. a teleprinter circuit or the line between two network switches). It contrasts with end-to-end encryption where messages are encrypted by the sender at the point of origin and only decrypted by the intended receiver. Link encryption offers a couple of advantages:

• encryption is automatic so there is less opportunity for human error.
• if the communications link operates continuously and carries an unvarying level of traffic, link encryption defeats traffic analysis.

On the other hand, end-to-end encryption ensures only authorized persons see the plaintext.

Link encryption can be used with end-to-end systems by superencrypting the messages.

Bulk encryption refers to encrypting a large number of circuits at once, after they have been multiplexed.

SSL encryption SSL is short for Secure Sockets Layer, and it is a protocol initially developed for transmitting private documents or information via the Internet. It essentially works through a cryptographic system that secures a connection between a client and a server. Many websites use this protocol to obtain confidential user information and it is supported in all modern browsers.

SSL encryption is turned on automatically for all Professional accounts. With this enabled, you can do the following:

Send encrypted URLs to your audience. The link and survey pages are secured by Verisign during transmission from your account to your respondents and then back into your account. Download your collected data over a secure channel. Comply with the security policies of your company or institution.