"RPyC 3.0+, in a nutshell, has two modes to it: a "classic mode," which was already available prior to its version 3, and a "services mode," which was introduced in version 3. The classic mode lacks any real security framework (which isn't always a bad thing) and simply presents remote machines as if they were local resources. The newer, services, mode isolates a collection of published interfaces that a server supports and is secure inasmuch as it prohibits everything not explicitly permitted. The classic mode is essentially identical to Pyro (without Pyro's optional security framework); the service mode is essentially RPC (for example, XML_RPC), modulo some details on calling conventions and implementation."