When your device connects to the Particle cloud, if often can do so by resuming the previous session. This dramatically reduces the amount of data used, from around 5-6 Kbytes of data for a full handshake to hundreds of bytes of data for a resume. While a full session handshake does not use data operations, if done excessively it can impact the total data usage on cellular devices. Sessions are automatically renegotiated every 3 days for security reasons.
Under normal circumstances you will never have to manually invalidate the current session. However, if you have a need to do so, this is the best way:
auto opts = CloudDisconnectOptions().clearSession(true); Particle.disconnect(opts);
You may see references to
spark/device/session/end in the community forums, however that method should not be used and may be deprecated in the future. The clearSession flag should be used instead.