Your new RiOS software is backward compatible with previous RiOS versions. However, to obtain the full benefits of the new features in this version, you must upgrade the client-side and server-side SteelHeads on any given WAN link. After you have upgraded all appliances, all the benefits of the new RiOS features and enhancements are available.

If you mix RiOS software versions in your network, you might not be able to take full advantage of new features that are not part of earlier software versions.