Multicast messaging may be managed in a machine-to-machine/Internet of things context, such as a CoAP network, via the inclusion of server selection criterion in multicast request messages and/or resource directory registration management. Server selection criteria may be explicit or implicit. An explicit criterion may be expressed, for example, as an IP address, a server identifier relative to a group context, or a Bloom filter. An implicit criterion may, for example, relate to the context of the request or the requestor, and include such information as data accuracy, data type, application, operating system, network location, geolocation, resource creation time, and resource update time. Server selection criteria may be maintained by a resource directory and/or via a user interface.