The complete process for incoming and outgoing messages is visualized below. The class CoapStack builds up the part between the Stack Top and Bottom.
+-----------------------+ | {@link MessageDeliverer} |+-------------A---------+ A * A +-----------+-A---------+ | CoAPEndpoint | | v A | | v A | | +---------v-+-------+ | | | Stack Top | | | +-------------------+ | | | {@link TokenLayer } | || +-------------------+ | | | {@link ObserveLayer} | || +-------------------+ | | | {@link BlockwiseLayer} | || +-------------------+ | | | {@link ReliabilityLayer} | || +-------------------+ | | | Stack Bottom | | | +---------+-A-------+ | | v A | | Matcher | | v A | | Interceptor | | v A | +-----------v-A---------+ v A v A +-----------v-+---------+ | {@link Connector} |+-----------------------+ | |