There are two different versions of SBLP. While SBLP via Discord, the first one, is more easy to implement for most people, it is less scalable and less compatible with other bots. The new version, SBLP via HTTP, however, is more scalable and compatible with most modern bump bots.
Both SBLP via Discord and SBLP via HTTP are decentralized solutions. While the first one requires a Discord channel for the communication, this could be any channel and does not need to be an official one. SBLP via HTTP works using direct HTTP requests between the compatible bots and do not require a central server.
You can find a documentation of both versions at GitHub.
Since SBLP via HTTP requires the bots to keep track of other compatible bots and needs to handle authorization of all of those, it can take some time for a developer to implement and also need to reconfigured every time a new bot is added, SBLP Centralized was created. It is a central server that keeps track of all compatible bots. It gives you an easy endpoint to quickly broadcast your bump request to all other bots, while also handling the receiving and authorization of other bots’ bump requests. It will check other bots’ identity and forward their requests to your bot’s server.
While making it easier for developers to implement SBLP Centralized, it also increases security as it proxies all requests from other bots and to other bots. Therefore, no other bot will ever be aware of your server’s actual IP.
The documentation of SBLP Centralized is available as a google document. You can find it here.