A method for memory protection in a data processing network, the method comprising: at a first cross-point switch of a plurality of cross-point switches of a coherent interconnect: receiving, from a first requesting node coupled to the first cross-point switch, a request message including an action request for data associated with a first memory address in a shared memory, the first cross-point switch including a first memory protection unit, wherein the coherent interconnect couples the plurality of cross-point switches, a home node and the shared memory; receiving, by the first memory protection unit, the request message from the first requesting node; determining, by the first memory protection unit, the one or more access permissions dependent upon the first memory address; augmenting, by the first memory protection unit, the request message with the one or more access permissions for the first requesting node; sending, from the first memory protection unit to the home node, the augmented request message; and at the home node of the coherent interconnect: determining, from the one or more access permissions of the augmented request message, if the requested action is permitted by the first requesting node; when the requested action is permitted by the first requesting node, accessing the data associated with the first memory address from a system cache, a local cache of a second requesting node coupled to a second cross-point switch of the coherent interconnect or the shared memory in accordance with a coherency protocol; and when the requested action is not permitted by the first requesting node, sending a response message to the first requesting node without accessing the data associated with the first memory address. at a first cross-point switch of a plurality of cross-point switches of a coherent interconnect: receiving, from a first requesting node coupled to the first cross-point switch, a request message including an action request for data associated with a first memory address in a shared memory, the first cross-point switch including a first memory protection unit, wherein the coherent interconnect couples the plurality of cross-point switches, a home node and the shared memory; receiving, by the first memory protection unit, the request message from the first requesting node; determining, by the first memory protection unit, the one or more access permissions dependent upon the first memory address; augmenting, by the first memory protection unit, the request message with the one or more access permissions for the first requesting node; sending, from the first memory protection unit to the home node, the augmented request message; and at the home node of the coherent interconnect: determining, from the one or more access permissions of the augmented request message, if the requested action is permitted by the first requesting node; when the requested action is permitted by the first requesting node, accessing the data associated with the first memory address from a system cache, a local cache of a second requesting node coupled to a second cross-point switch of the coherent interconnect or the shared memory in accordance with a coherency protocol; and when the requested action is not permitted by the first requesting node, sending a response message to the first requesting node without accessing the data associated with the first memory address. determining, from the one or more access permissions of the augmented request message, if the requested action is permitted by the first requesting node; when the requested action is permitted by the first requesting node, accessing the data associated with the first memory address from a system cache, a local cache of a second requesting node coupled to a second cross-point switch of the coherent interconnect or the shared memory in accordance with a coherency protocol; and when the requested action is not permitted by the first requesting node, sending a response message to the first requesting node without accessing the data associated with the first memory address.