Port 593
HTTP RPC Endpoint Mapper
Port 593 is primarily used for Remote Procedure Call (RPC) communications over HTTP, facilitating DCOM (Distributed Component Object Model) services within Microsoft ecosystems. It enables client-server communication, component activation, and method invocation, typically in distributed enterprise applications and Exchange servers. Since it multiplexes RPC traffic over HTTP, it also helps traverse firewall restrictions while maintaining interoperability between networked services..
Technical Details
Port 593, designated for HTTP RPC Endpoint Mapper, facilitates the transmission of Remote Procedure Call requests over the HTTP protocol. This capability expands traditional RPC functionality, allowing remote components and applications to communicate seamlessly across diverse network environments. HTTP encapsulation makes RPC traffic more firewall-friendly, as many network boundaries permit HTTP where direct RPC might be restricted.
In a typical Microsoft environment, this port is instrumental in enabling DCOM services. It supports the activation and invocation of distributed software components, essential for enterprise applications including Microsoft Exchange Server. Through the RPC Endpoint Mapper function, it assists client applications to locate network services by resolving endpoint addresses dynamically, without needing to hard-code port numbers.
The implementation leverages the standard HTTP protocol stack, making it compatible with existing web infrastructure. This means RPC over HTTP can traverse proxies and NAT devices more easily than native RPC, increasing reachability for distributed components. However, it requires careful configuration to ensure that multiplexed services are functioning correctly and securely.