The enhancements to the default Transport Layer Security (TLS)/Secure Socket Layer (SSL) cipher suites helps ensure that connections are better encrypted during transmission. In addition, enabling Perfect Forward Secrecy (PFS) helps ensure a different encryption key is used for every connection, making it more difficult for attackers to decrypt connections.
Read more here – http://blogs.technet.com/b/trustworthycomputing/archive/2014/08/07/strengthening-encryption-for-microsoft-azure-customers.aspx