addChannelHandler(ENCODER, new CoapMessageEncoder());
addChannelHandler(DECODER, new CoapMessageDecoder());
addChannelHandler(OUTBOUND_RELIABILITY_HANDLER, new OutboundReliabilityHandler(executor));
addChannelHandler(CLIENT_OBSERVATION_HANDLER, new ClientObservationHandler());
addChannelHandler(CLIENT_CALLBACK_MANAGER, new ClientCallbackManager(executor, tokenFactory));
}