1. A method performed by a receiving node in a network, comprising: the receiving node receiving an indication from the network that a sending node wants to send data to the receiving node, the indication from the sending node including a field for identifying a request for sending data using token identifiers; the receiving node sending to the sending node a token identifier identifying a memory location on the receiving node, an offset value that is updated when a transfer is split into multiple packets, and a data size for the memory location, the token identifier being a value that acts as an index into a token array, which identifies the memory location, but is not a physical or virtual address, so that the sending node is unaware of the memory location; the receiving node receiving from the sending node the token identifier and at least a first portion of the data; writing the data to the receiving node at the memory location; using a first token identifier array for processing the data, if the data is unexpected, as indicated by a field of the token identifier; and using a second token identifier array for processing the data, if the data is expected.