Security Sidebar: Google Leads The Way On Sunsetting SHA-1
SHA-1 (or Secure Hash Algorithm) is a cryptographic algorithm that was developed by the National Security Agency in the 1990s and is widely used in popular cryptographic protocols like Secure Sockets...
I would choose RSA. The DSA (Digital Signature Algorithm) can utilize SHA-1 as its cryptographic hash function, but it doesn't have to. For more info on the SSL cipher suites supported by each version of BIG-IP, check out this link: https://support.f5.com/kb/en-us/solutions/public/13000/100/sol13163.html
Hope this helps!
John