Communication protocols for processing an authorization request in a distributed computing system

A non-transitory computer storage medium storing instructions configured to instruct a computing system to implement a communication protocol, the communication protocol comprising:

• establishing a communication connection between a portal and a reader that is connected to a destination account controller, wherein the communication connection does not go through the destination account controller controlling a destination account associated with the reader;
• receiving, in the portal through the communication connection from the reader, a first authorization request identifying a source account identifier obtained by the reader from a mobile device;
• transmitting, by the portal in response to the first authorization request and based on data linking the source account identifier and a linked identifier, a second authorization request to a linked account controller controlling a linked account identified by the linked identifier, the second authorization request including the linked account identifier;
• receiving, by the portal from the linked account controller, a first response to the second authorization request, the first response identifying an available resource for transferring from the linked account to the destination account;
• and
• communicating, by the portal, the first response to the reader to cause the reader to generate a third authorization request based on the available resource identified in the first response and transmit the third authorization request, the third authorization request including the source identifier and a requested resource to be transferred to the destination account;
• receiving, by a centralized router, the third authorization request from the reader via the destination account controller;
• routing, by the centralized router, the third authorization request to a source account controller that controls a source account identified by the source identifier contained in the third authorization request;
• and
• routing, by the centralized router, a second response to the third authorization request from the source account controller to the reader via the destination account controller.

A method for implementing a communication protocol, the method comprising:

• establishing a communication connection between a portal and a reader that is connected to a destination account controller, wherein the communication connection does not go through the destination account controller controlling a destination account associated with the reader;
• receiving, in the portal through the communication connection from the reader, a first authorization request identifying a source account identifier obtained by the reader from a mobile device;
• transmitting, by the portal in response to the first authorization request and based on data linking the source account identifier and a linked identifier, a second authorization request to a linked account controller controlling a linked account identified by the linked identifier, the second authorization request including the linked account identifier;
• receiving, by the portal from the linked account controller, a first response to the second authorization request, the first response identifying an available resource for transferring from the linked account to the destination account;
• and
• communicating, by the portal, the first response to the reader to cause the reader to generate a third authorization request based on the available resource identified in the first response and transmit the third authorization request, the third authorization request including the source account identifier and a requested resource to be transferred to the destination account;
• receiving, by a centralized router, the third authorization request from the reader via the destination account controller;
• routing, by the centralized router, the third authorization request to a source account controller that controls a source account identified by the source identifier contained in the third authorization request;
• and
• routing, by the centralized router, a second response to the third authorization request from the source account controller to the reader via that destination account controller.