Elante company has recently hired James as a penetration tester. He was tasked with performing enumeration on an organization's network. In the process of enumeration, James discovered a service that

Border Gateway Protocol (BGP) typically uses port 179 for establishing peering sessions between routers.

FTP (File Transfer Protocol) is a standard network protocol used for the transfer of computer files between a client and server on a computer network. It commonly uses port 21 for its control connection, which is used to send commands and replies.

Network File System (NFS) primarily uses port 2049, along with other ports for RPC services.

Remote Procedure Call (RPC) services can use various ports, often dynamically assigned or registered with a port mapper (port 111 for ONC RPC), but not primarily port 21.