A computer implemented method for facilitation of deterministic management of a plurality of electronic message packets comprising orders to trade communicated to an application via a network from a plurality of message sources (210, 211, 212, 213) comprising market participants, the application comprising an order entry gateway for use with an exchange operational to match trades using the electronic message packets, the method comprising: receiving, by a processor, each of the plurality of electronic message packets from the network at a common destination to which all of the plurality of electronic message packets are directed, wherein the common destination comprises the application; determining, by the processor at the common destination automatically upon receipt thereof prior to each of the received electronic message packet being provided to the application, an order in which each electronic message packet was received relative to the reception of others of the plurality of electronic message packets, the order being determined irrespective of which message source of the plurality of message sources (210, 211, 212, 213) each of the received electronic message packets originated; the method is characterised by storing, by the processor in a memory coupled with the processor, the received plurality of electronic message packets in an arrangement which associates the received electronic message packets according to a same respective message source of the plurality of message sources (210, 211, 212, 213) from which each of the received electronic message packets respectively originated irrespective of the time of receipt thereof; and providing the determined order to the application; wherein the application accesses the received electronic message packets in the memory according to the determined order irrespective of the message source. receiving, by a processor, each of the plurality of electronic message packets from the network at a common destination to which all of the plurality of electronic message packets are directed, wherein the common destination comprises the application; determining, by the processor at the common destination automatically upon receipt thereof prior to each of the received electronic message packet being provided to the application, an order in which each electronic message packet was received relative to the reception of others of the plurality of electronic message packets, the order being determined irrespective of which message source of the plurality of message sources (210, 211, 212, 213) each of the received electronic message packets originated; the method is characterised by storing, by the processor in a memory coupled with the processor, the received plurality of electronic message packets in an arrangement which associates the received electronic message packets according to a same respective message source of the plurality of message sources (210, 211, 212, 213) from which each of the received electronic message packets respectively originated irrespective of the time of receipt thereof; and providing the determined order to the application; wherein the application accesses the received electronic message packets in the memory according to the determined order irrespective of the message source.