LayerZero Endpoint is the only interface for a User Application (UA). The Endpoint allows UAs to configure the Messaging Library used for sending and receiving verified messages, and guarantees the message delivering ordering across all messaging libraries.
Send(): the message will be sent through the endpoint first and then redirected to the UA-configured Messaging Library
Receive(): the message will be verified at the Messaging Library first then forwarded to the endpoint and eventually delivered to the UA.
All Messaging Libraries, once deployed, will be in service in perpetuity, which means that no entity, including the LayerZero Labs multi-sig, can de-register any Messaging Library or change the Messaging Library configuration of a UA, i.e. if the UA has specified a Messaging Library to use, no entity can stop the messaging flow.
LayerZero can deploy new Messaging Libraries for security and performance optimization (e.g. more efficient proof technologies). This allows LayerZero to bring the best research into production and support the system with the best technology. The UA interface won't change and UA can simply migrate to any new version with ease. For each Messaging Library (e.g. Ultra-Light Node), LayerZero can deploy new proof validation libraries for security or performance reasons.
If the UA has specified a validation library to use, no entity can change the configuration.