# US 11,310,017 B2 · Preemptive expectation message for triggering transmission of expected message in deterministic wireless network > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,310,017 B2 - Document ID: US11310017B2 - Status: Granted - Kind: B2 - Application number: 16/747,399 - Filed: 2020-01-20 - Published: 2021-07-08 - Granted: 2022-04-19 - Earliest claimed: 2020-01-02 - Assignees: Cisco Technology, Inc. - Applicants: Cisco Technology, Inc. - Inventors: Pascal Thubert; Eric Michel Levy-Abegnoli - Web page: https://patentgrep.com/patent/US11310017B2 ## CPC - H04L 5/0053: {Allocation of signalling, i.e. of overhead other than pilot signals} - H04W 74/085: {collision avoidance} - H04W 72/0446: Resources in time domain, e.g. slots or frames - H04W 74/004: {in the uplink, i.e. towards network} - H04W 74/04: Scheduled access (hybrid access H04W74/02) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract In one embodiment, a method comprises: identifying, by a receiving network device, a deterministic schedule comprising allocated time slots, each allocated time slot allocated for the receiving network device receiving a data packet from one of a plurality of transmitting network devices in a wireless deterministic data network; and selectively transmitting, by the receiving network device, an expectation message at initiation of each of the allocated time slots, each expectation message preempting transmission by any other network device during the corresponding allocated time slot, each expectation message generated by the receiving network device and identifying a corresponding transmitting network device that is expected to deterministically transmit a corresponding expected data packet to the receiving network device during the corresponding allocated time slot; the expectation message causing the corresponding identified transmitting network device to transmit the corresponding expected data packet during the corresponding allocated time slot. ## Claims ### Claim 1 A method comprising: identifying, by a receiving network device, a deterministic schedule comprising allocated time slots, each allocated time slot allocated for the receiving network device receiving a data packet from one of a plurality of transmitting network devices in a wireless deterministic data network; and selectively transmitting, by the receiving network device, an expectation message at initiation of each of the allocated time slots, each expectation message preempting transmission by any other network device during the corresponding allocated time slot, each expectation message generated by the receiving network device and identifying a corresponding transmitting network device that is expected to deterministically transmit a corresponding expected data packet to the receiving network device during the corresponding allocated time slot; the expectation message causing the corresponding identified transmitting network device to transmit the corresponding expected data packet during the corresponding allocated time slot; the method further comprising suppressing transmission of the expectation message during one of the allocated time slots reserved for retransmissions in response to reception of the corresponding expected data packet during an earlier second allocated time slot, the suppressing transmission causing another network device to reclaim the one allocated time slot in response to a determined absence of the expectation message. ### Claim 2 (depends on 1) The method of claim 1, wherein the expectation message eliminates any necessity of any acknowledgment message following transmission of the expected data packet during the corresponding allocated time slot. ### Claim 3 (depends on 1) The method of claim 1, wherein the suppressing transmission includes: detecting, during a corresponding third allocated time slot allocated for a first transmitting network device and earlier than the second allocated time slot, an absence of receiving the expected data packet from the first transmitting network device following transmission, by the receiving network device, of the corresponding expectation message identifying the first transmitting network device is expected to deterministically transmit the expected data packet during the third allocated time slot; and receiving the expected data packet during the second allocated time slot from a second transmitting network device following transmission, by the receiving network device, of the corresponding expectation message identifying the second transmitting network device is expected to deterministically transmit the expected data packet during the second allocated time slot. ### Claim 4 (depends on 1) The method of claim 1, wherein: the identifying includes identifying, among the allocated time slots, first allocated time slots allocated for reception of data packets from respective transmitting network devices and second allocated time slots allocated for retransmission by any of the respective transmitting network devices selected by the receiving network device; the method further comprises the receiving network device detecting an absence of receiving a first expected data packet during a corresponding one of the first allocated time slots following the corresponding expectation message identifying the first expected data packet from a first transmitting network device, and selecting any one of the second allocated time slots for retransmission of the first expected data packet; the selectively transmitting including the receiving network device transmitting, during the one second allocated time slot, a second expectation message identifying the first transmitting network device is expected to retransmit the first expected data packet. ### Claim 5 (depends on 4) The method of claim 4, further comprising the receiving network device selecting the first expected data packet for retransmission based on a determined priority relative to a second expected data packet awaiting retransmission. ### Claim 6 (depends on 1) The method of claim 1, wherein the selectively transmitting includes the receiving network device inserting, into the expectation message, a device identifier for the corresponding transmitting network device, and an identifier associated with the corresponding expected data packet. ### Claim 7 (depends on 6) The method of claim 6, wherein the identifier associated with the corresponding expected data packet includes at least one of a flow identifier or a sequence identifier. ### Claim 8 (depends on 1) The method of claim 1, wherein the selectively transmitting includes transmitting the expectation message during a Clear Channel Assessment (CCA) phase at a beginning of the corresponding allocated time slot, the expectation message causing any other network device detecting the expectation message during the CCA phase to refrain from any transmission during the corresponding allocated time slot. ### Claim 9 (depends on 1) The method of claim 1, wherein: the method further comprises the network device determining an upcoming data packet does not need to be transmitted during an upcoming allocated time slot by a corresponding scheduled transmitting network device; the selectively transmitting includes generating and sending, at initiation of the upcoming allocated time slot, a null expectation message that causes the corresponding scheduled transmitting network device to drop the upcoming data packet. ### Claim 10 An apparatus implemented as a physical machine, the apparatus comprising: non-transitory machine readable media configured for storing executable machine readable code; a device interface circuit configured for receiving a data packet via a deterministic network; and a processor circuit configured for executing the machine readable code, and when executing the machine readable code operable for: identifying, by the apparatus implemented as a receiving network device, a deterministic schedule comprising allocated time slots, each allocated time slot allocated for the receiving network device receiving a data packet from one of a plurality of transmitting network devices in a wireless deterministic data network, and selectively transmitting, by the device interface circuit, an expectation message at initiation of each of the allocated time slots, each expectation message preempting transmission by any other network device during the corresponding allocated time slot, each expectation message generated by the processor circuit and identifying a corresponding transmitting network device that is expected to deterministically transmit a corresponding expected data packet to the receiving network device during the corresponding allocated time slot; the expectation message causing the corresponding identified transmitting network device to transmit the corresponding expected data packet during the corresponding allocated time slot; wherein the processor circuit is configured for suppressing transmission of the expectation message during one of the allocated time slots reserved for retransmissions in response to reception of the corresponding expected data packet during an earlier second allocated time slot, the suppressing transmission causing another network device to reclaim the one allocated time slot in response to a determined absence of the expectation message. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein the expectation message eliminates any necessity of any acknowledgment message following transmission of the expected data packet during the corresponding allocated time slot. ### Claim 12 (depends on 10) The apparatus of claim 10, wherein the processor circuit is configured for: detecting, during a corresponding third allocated time slot allocated for a first transmitting network device and earlier than the second allocated time slot, an absence of receiving the expected data packet from the first transmitting network device following transmission, by the receiving network device, of the corresponding expectation message identifying the first transmitting network device is expected to deterministically transmit the expected data packet during the third allocated time slot; and receiving the expected data packet during the second allocated time slot from a second transmitting network device following transmission, by the receiving network device, of the corresponding expectation message identifying the second transmitting network device is expected to deterministically transmit the expected data packet during the second allocated time slot. ### Claim 13 (depends on 10) The apparatus of claim 10, wherein: the processor circuit is configured for identifying, among the allocated time slots, first allocated time slots allocated for reception of data packets from respective transmitting network devices and second allocated time slots allocated for retransmission by any of the respective transmitting network devices selected by the processor circuit; the processor circuit further configured for detecting an absence of receiving a first expected data packet during a corresponding one of the first allocated time slots following the corresponding expectation message identifying the first expected data packet from a first transmitting network device, and selecting any one of the second allocated time slots for retransmission of the first expected data packet; the processor circuit further configured for causing the device interface circuit to transmit, during the one second allocated time slot, a second expectation message identifying the first transmitting network device is expected to retransmit the first expected data packet. ### Claim 14 (depends on 10) The apparatus of claim 10, wherein the processor circuit is configured for inserting, into the expectation message, a device identifier for the corresponding transmitting network device, and an identifier associated with the corresponding expected data packet. ### Claim 15 (depends on 10) The apparatus of claim 10, wherein the selectively transmitting includes transmitting the expectation message during a Clear Channel Assessment (CCA) phase at a beginning of the corresponding allocated time slot, the expectation message causing any other network device detecting the expectation message during the CCA phase to refrain from any transmission during the corresponding allocated time slot. ### Claim 16 (depends on 10) The apparatus of claim 10, wherein the processor circuit is configured for: determining an upcoming data packet does not need to be transmitted during an upcoming allocated time slot by a corresponding scheduled transmitting network device; generating and sending, at initiation of the upcoming allocated time slot, a null expectation message that causes the corresponding scheduled transmitting network device to drop the upcoming data packet. ### Claim 17 One or more non-transitory tangible media encoded with logic for execution by a machine and when executed by the machine operable for: identifying, by the machine implemented as a receiving network device, a deterministic schedule comprising allocated time slots, each allocated time slot allocated for the receiving network device receiving a data packet from one of a plurality of transmitting network devices in a wireless deterministic data network; and selectively transmitting, by the receiving network device, an expectation message at initiation of each of the allocated time slots, each expectation message preempting transmission by any other network device during the corresponding allocated time slot, each expectation message generated by the receiving network device and identifying a corresponding transmitting network device that is expected to deterministically transmit a corresponding expected data packet to the receiving network device during the corresponding allocated time slot; the expectation message causing the corresponding identified transmitting network device to transmit the corresponding expected data packet during the corresponding allocated time slot; the one or more non-transitory tangible media further operable for suppressing transmission of the expectation message during one of the allocated time slots reserved for retransmissions in response to reception of the corresponding expected data packet during an earlier second allocated time slot, the suppressing transmission causing another network device to reclaim the one allocated time slot in response to a determined absence of the expectation message. ### Claim 18 (depends on 17) The one or more non-transitory tangible media of claim 17, wherein the expectation message eliminates any necessity of any acknowledgment message following transmission of the expected data packet during the corresponding allocated time slot.