A communication method between service modules in a system in which service modules operating on a plurality of information processing apparatuses connected with a network operate in collaboration with each other, the system includes a monitoring apparatus that is provided with a monitor module monitoring a connection between service modules in the system and that has connection management information including identifier information for uniquely identifying an information processing apparatus in which a service module is operating in the system, and connection information including external connection information for the service module to perform communication using an external network between the information processing apparatuses and internal connection information for the service module to perform communication using an internal network of the information processing apparatus.