I just tried to update the initial post, but unfortunately, editing is only allowed for a certain and then the post is “frozen”. So, I post my update here:
Here is the updated figure:
The important point is that the API Boundary Nodes are managed by the NNS and expose the Internet Computer API endpoints (query, call, read_state, and status`) as defined in the Interface Specification. Anybody can run an application in front of these API Boundary Nodes. So far, we here at DFINITY have been focusing on HTTP gateways to enable browser access. However, there is room for many different gateways: for example, DNS gateways that allow hosting your DNS records on-chain (see here for more information) or an SMTP/XMPP/MQTT gateway for emails/messaging. This just shows the versatility of the Internet Computer: through gateways (“adapters”), we can connect web2 to web3.