Advanced features are available for tailoring the protocol configuration to the disparate needs of IoT applications, such asproxying(a smart object contacts an intermediary which can respond with a cached copy of a resource or ask the “real” server an updated copy, depending on a freshness model),resource discovery(some resources with index capabilities must be implemented by all CoAP servers),blockwise transfer(some access networks, like IEEE 802.15.4, have a very limited Maximum Transfer Unit (MTU), with CoAP it is possible to segment the requests/responses
in multiple chucks separately acknowledged), observation(clients can subscribe to a document and then get a new version whenever it is updated).
CoAP can be also used to enable management functions, like device management, as
described in [18] for the OMA-MD (Open Mobile AllianceDevice Management).