Selecting and ranking cipher suites for SSL

A secure socket layer (SSL) connection begins with a negotiation in which the client and server present a list of supported cipher suites in a priority sequence. A cipher suite provides the quality of protection for the connection. It contains cryptographic, authentication, hash, and key exchange algorithms. The SSL protocol selects the highest priority suite that the client and the server both support.

A list of supported cipher suites for SSL is provided. You can eliminate cipher suites that do not meet your requirements and then assign a priority, or preference, to the remaining cipher suites. The selected cipher suites are presented in priority sequence for the client and server sides of the negotiation. At least one of the selected cipher suites between the client and server platforms must match.

The list of supported cipher suites is dynamically generated on each computer, and depends on the Java™ Runtime Environment (JRE) or whether you have other cryptographic software installed on the computer. If you have made changes to a computer, such as upgraded the JRE or installed software that has upgraded the JRE, this may affect the supported cipher suites available on that computer. If you no longer have a supported cipher suite that matches the other computers in your environment, you may have to change the JRE on the computer to match the other computers in your environment.

Procedure

  1. Start IBM® Cognos® Configuration.
  2. In the Explorer window, click Cryptography > Cognos.
  3. In the Properties window, click the Value column for the Supported ciphersuites property.
  4. Click the edit icon Actions icon.
    • To move a cipher suite to the Current values list, click the check box in the Available values list and then click Add.
    • To move a cipher suite up or down in the Current values list, click the check box and then click the up or down arrows.
    • To remove a cipher suite from the Current values list, click the check box and then click Remove.
  5. Click OK.
  6. From the File menu, click Save.