Apparatus and methods for reduction of transmission delay in a communication network

• US 9,641,456 B2
• Filed: 09/30/2012
• Issued: 05/02/2017
• Est. Priority Date: 05/31/2007
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Inventors: Ohana, Yitshak, Klein, Philippe, Kliger, Avi, Palm, Stephen
• Primary Examiner(s): Yao, Kwang B
• Assistant Examiner(s): Loo, Juvena
• Application Number:
  US13/632,023
• Publication Number:
  US 20130039186A1
• Time in Patent Office: 1,675 Days
• Field of Search: 370310-463
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04L 49/206 Real Time traffic
• CPC Class Codes: H04L 49/351 for local area network [LAN], e.g. Ethernet switches

Abstract

Apparatus and methods for reducing latency in coordinated networks are provided. The apparatus and methods relate to a protocol that may be referred to as the Persistent Reservation Request (“p-RR”), which may be viewed as a type of RR (reservation request). p-RR'"'"'s may reduce latency, on average, to one MAP cycle or less. A p-RR may be used to facilitate Ethernet audiovisual bridging. Apparatus and methods of the invention may be used in connection with coaxial cable based networks that serve as a backbone for a managed network, which may interface with a package switched network.

Claims

1. A method comprising:

receiving from a first node a persistent reservation request for allocation of network resources for transmission, by the first node via a first networking specification, of data frames not yet received by the first node from a second node via a second networking specification that differs from the first networking specification, wherein the persistent reservation request is for transmission of a first data frame in a first media access plan (“

MAP”

) cycle and for transmission of a second data frame in a second MAP cycle, each of said first data frame and said second data frame that has not yet been received by the first node, each of the first data frame and the second data frame being addressed via the second networking specification to a third node, the persistent reservation request having been generated responsive to a reservation message received by the first node from the second node via the second networking specification, characteristics of the persistent reservation request and the first and second data frames for transmission being indicated by the first networking specification, characteristics of the data frames not yet received by the first node indicated by the second networking specification, and the first node being in communication with a first network that corresponds to the first networking specification and a second network that corresponds to the second networking specification; and

establishing a latency-reducing data flow comprising the first data frame and the second data frame, said establishing being based, as least in part, on the persistent reservation request,

wherein the latency-reducing data flow is initiated prior to both the first data frame and the second data frame being received by the first node.

2. The method of claim 1 wherein the persistent reservation request comprises a traffic specification.

3. The method of claim 2 further comprising canceling the latency-reducing data flow based on information included in the traffic specification.

4. The method of claim 1 further comprising canceling the latency-reducing data flow based on execution of a link maintenance operation process.

5. The method of claim 1, wherein the establishing comprises allocating network resources during a portion of at least one medium access plan cycle, the portion having a duration that is less than a duration of the medium access plan cycle.

6. The method of claim 1, wherein the first networking specification comprises a non-Ethernet networking specification and the second networking specification comprises an Ethernet networking specification.

7. A device comprising:

a receiver circuit in communication with a first network, the receiver circuit configured to receive a first reservation request from a first node in communication with the first network, wherein the first reservation request is for allocation of network resources for transmission, by a transmitter circuit of the first node via a first communication protocol of the first network, of at least a first and a second data frame not yet received by the first node from a second node via a second communication protocol of a second network, each of the first data frame and the second data frame being addressed via the second communication protocol to a third node, the first reservation request having been generated responsive to a reservation message received by the first node, characteristics of the first reservation request being indicated by the first communication protocol and characteristics of the first and second data frames not yet received being indicated by the second communication protocol;

a processor circuit in communication with the receiver circuit, the processor circuit configured to establish a latency-reducing data flow based on the first reservation request; and

the transmitter circuit configured to inform the first node of a grant of the first reservation request, the grant authorizing the first node to transmit the first data frame in a first media access plan (“

MAP”

) cycle and the second data frame in a second MAP cycle,

wherein the transmitter circuit is configured to inform the first node of the grant of the first reservation request prior to the first node receiving the second data frame.

8. A method comprising:

receiving, at a first node over a first network that corresponds to a first networking specification, a registration request, the registration request requesting receipt of multicast information by a second node from a third node, the registration request including a traffic specification;

transmitting, using the first node, the registration request to the third node over a second network that corresponds to a second networking specification that differs from the first networking specification;

receiving, at the first node and responsive to the registration request, a first reservation request from the third node over the second network;

generating, using the first node and in response to receiving the first reservation request, a second reservation request for transmission over the first network, the second reservation request differing from the first reservation request; and

transmitting, using the first node, the second reservation request to a network coordinator of the first network, the second reservation request conforming to the traffic specification,

wherein;

the first node transmits at least two frames of multicast data over the first network, each transmission occurring in a discrete media access plan (“

MAP”

) cycle prior to transmitting a third reservation request to the network coordinator of the first network.

9. The method of claim 8 further comprising, when the network coordinator generates medium access plan cycles and the second reservation request corresponds to one of the media access plan cycles, transmitting at least one additional reservation request, each of the at least one additional reservation request being transmitted in a respective subsequent media access plan cycle.

10. The method of claim 8, further comprising:

receiving, by the first node, a grant from the network coordinator in response to the second reservation request, the grant not being provided to the third node.

11. A method comprising:

transmitting a reservation request to a network coordinator for allocation of network resources on a non-packet-switched network segment during at least two medium access plan cycles for data that has not been received;

receiving, subsequent to transmitting the reservation request, the data from a first packet-switched network segment using a packet-switched network ingress port, wherein the data is addressed to a node of a second packet-switched network segment via a communication protocol associated with the second packet-switched network segment; and

transmitting the data over the non-packet-switched network segment to the second packet-switched network segment using a non-packet-switched network egress port.

12. The method of claim 11 further comprising, using the non-packet-switched network egress port, transmitting to the network coordinator a data flow request for data flow from the packet-switched network ingress port to the non-packet-switched network egress port.

13. The method of claim 11 further comprising:

transmitting to the network coordinator the reservation request for the allocation of network resources for transmitting the data to the non-packet-switched network egress port; and

transmitting at least two frames of the data before transmitting a second reservation request to the network coordinator.

14. The method of claim 11, further comprising, when the network coordinator generates medium access plan cycles:

transmitting to the network coordinator the reservation request for the allocation of network resources for transmitting the data to the non-packet-switched network egress port, the reservation request corresponding to one of the generated medium access plan cycles; and

transmitting at least one additional reservation request, each of the at least one additional reservation requests being transmitted in a respective subsequent medium access plan cycle.

15. The method of claim 14 wherein communication over the non-packet-switched network segment is performed in accordance with protocols defined by a specification relating to transmission of data over a shared coaxial medium.

16. The method of claim 11, further comprising receiving a first reservation request from the first packet-switched network segment, wherein transmitting the reservation request is in response to receiving the first reservation request.

17. The method of claim 11, wherein the data is received with characteristics of a first communication protocol associated with the first packet-switched network segment and the data is transmitted with characteristics of a second communication protocol associated with the non-packet-switched network segment.

18. A method comprising:

transmitting, by a first node over a non-Ethernet network, a reservation request for requesting allocation of network resources for transmission, over the non-Ethernet network, of data frames not yet received by the first node over an Ethernet network, wherein the reservation request is for transmission of a first data frame in a first media access plan (“

MAP”

) cycle of the non-Ethernet network and for transmission of a second data frame in a second MAP cycle of the non-Ethernet network, each of said first data frame and said second data frame that has not yet been received by the first node from a second node over the Ethernet network at a time of the transmitting the reservation request, each of the first data frame and the second data frame being addressed via an Ethernet specification to a third node, the reservation request being transmitted in response to a reservation message received by the first node over the Ethernet network, the first node being in communication with the Ethernet network and the non-Ethernet network; and

in response to the reservation request, receiving from a network controller instructions to transmit the first data frame in the first MAP cycle of the non-Ethernet network and the second data frame in the second MAP cycle of the non-Ethernet network.

19. The method of claim 18 wherein the reservation request comprises a traffic specification.

20. The method of claim 18 further comprising:

transmitting the first data frame in the first MAP cycle and the second data frame in the second MAP cycle without transmitting a subsequent reservation request.

21. The method of claim 20, wherein the first data frame comprises a multicast data frame.

22. The method of claim 18, wherein the allocation of network resources is for a portion of at least one medium access plan cycle, the portion having a duration that is less than a duration of the medium access plan cycle.

23. A bridge device comprising:

a processor circuit configured to establish a latency-reducing data flow on a first network based on a reservation request, the latency-reducing data flow comprising a first data frame and a second data frame received from a first node over a second network that differs from the first network in at least message passing characteristics;

a transmitter circuit in communication with the first network, the second network, and the processor circuit, the transmitter circuit configured to transmit the reservation request in response to a reservation message received by the bridge device over the second network and prior to receipt of the first data frame and the second data frame by the bridge device over the second network, each of the first data frame and the second data frame being addressed to a second node via a network specification associated with the second network; and

a receiver circuit configured to receive a grant of the reservation request from a network controller of the first network, the grant authorizing the bridge device to transmit the first data frame in a first media access plan (“

MAP”

) cycle of the first network and the second data frame in a second MAP cycle of the first network.

24. The bridge device of claim 23, wherein:

the receiver circuit is further configured to receive the reservation message from the first node over the second network; and

the transmitter circuit is configured to transmit the reservation request over the first network.

25. A device comprising:

at least one processor circuit configured to;

receive, over a first network, a registration request, the registration request requesting receipt of multicast information by a first node from a second node, the registration request including a traffic specification;

transmit, over a second network that differs from the first network, the registration request to the second node;

receive, over the second network, a first reservation request from the second node responsive to the registration request; and

generate, responsive to the first reservation request received over the first network, a second reservation request for transmission over the second network;

transmit the second reservation request to a network coordinator of the first network, the second reservation request conforming to the traffic specification; and

transmit at least two frames of multicast data over one or more discrete media access plan (MAP) cycles of the first network prior to a transmission of a third reservation request to the network coordinator of the first network.

26. The device of claim 25, wherein the at least one processor circuit is configured to transmit the at least two frames over multiple discrete MAP cycles prior to the transmission of the third reservation request.

27. The device of claim 25, wherein the at least one processor circuit is configured to transmit the at least two frames in one discrete MAP cycle.