Methods and devices for network modeling, service provisioning, and service management are disclosed. A network modeling method includes accessing information describing a set of nodes of a communications network, physical links physically connecting the nodes, and logical links logically connecting the nodes using the physical links. The method further includes, based on the information, creating a different connection group object for each of the physical links and for each of the logical links. Each connection group object includes a connection representing the link, a first endpoint representing a first node of the set connected to the link; and a second endpoint representing a second node of the set connected to the link.