Interfacing messages between a host and a network

• US 8,144,606 B1
• Filed: 11/06/2008
• Issued: 03/27/2012
• Est. Priority Date: 11/15/2007
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Marvell International Limited (Marvell Technology Group Limited)
• Inventors: Viehweg, Frank, Althoff, Markus, Weber, Peter
• Primary Examiner(s): Rutkowski, Jeffrey M
• Application Number:
  US12/291,082
• Time in Patent Office: 1,237 Days
• Field of Search: 370221-224, 370/249, 370242-245, 370/248, 370/250, 370/389, 370/392, 370400-401, 375/221, 379/22.01, 398/167, 713/300, 710/22, 709/223, 709/224, 709/250
• US Class Current: 370/249
• CPC Class Codes: H04L 12/4625 Single bridge functionality, e.g. connection of two networks over a single bridge
• CPC Class Codes: H04L 43/00 Arrangements for monitoring or testing data switching networks
• CPC Class Codes: H04L 49/00 Packet switching elements

Abstract

Devices, systems, methods, and other embodiments associated with a network device for interfacing a host with a network are described. One example network device includes a transmit path, and a receive path. A loopback path connects the transmit path and the receive path. A frame detection logic is configured to monitor network traffic on the transmit path to identify loopback frames. When a loopback frame is detected, a loopback logic routes the identified loopback frame onto the loopback path and then to the receive path. The rerouted loopback frame may then be received by a host or an embedded client from the receive path.

Claims

1. A device, comprising:

a transmit path;

a receive path;

wherein the transmit path and the receive path are configured to provide, at least in part, network connectivity for a host device to a network;

a loopback path connecting the transmit path and the receive path;

an embedded processor within the device configured to execute an embedded client, wherein the embedded processor is connected to the transmit path for transmitting data to the network and is connected to the receive path for receiving data from the network;

a frame detection logic configured to monitor network traffic on the transmit path to identify loopback frames which include frames addressed to the embedded client; and

a loopback logic configured to reroute the identified loopback frames sent from the host device and addressed to the embedded client onto the loopback path and then to the receive path destined for the embedded client without the loopback frames being transmitted back to the host device.

2. The device of claim 1, wherein the loopback frames include frames that are addressed to the host device, and wherein the loopback logic is configured to reroute identified loopback frames addressed to the host device on the transmit path, sent from the embedded processor, to the receive path to be received by the host device.

3. The device of claim 1, where the frame detection logic and the loopback logic identify and reroute loopback frames transparently to the host device.

4. The device claim 1, where the loopback logic includes:

a transmit path multiplexer having an input connected to the transmit path and having a first output connected to the loopback path and a second output that continues the transmit path to the network; and

a receive path multiplexer having a first input connected to receive frames from the network and a second input to receive frames from the loopback path, and having an output connected to the receive path.

5. The device of claim 1, where the frame detection logic is configured to identify loopback frames by a predetermined data pattern, and configured to mark the loopback frames with a loopback marking;

and

where the loopback logic reroutes loopback frames that contain the loopback marking.

6. The device of claim 5, where the loopback marking is a status bit within the loopback frames.

7. The device of claim 1, where the frame detection logic detects the loopback frames by detecting a desktop and mobile architecture for system hardware (DASH) pattern within the loopback frames.

8. The device of claim 1, further including:

a buffer to store network frames received from a network; and

a receive path controller to control whether the network frames from the buffer or network frames from the loopback path are passed to the receive path.

9. The device of claim 1, where the device is an Ethernet device to provide network connectivity for the host device.

10. The device of claim 8, where the receive path controller is a multiplexer.

11. The device of claim 1, further including:

a medium access controller (MAC) connected to the transmit path and the receive path to control network communications between the device and a network.

12. The device of claim 1, further including:

a multiplexer configured to control whether frames sent from an embedded client within the device or sent from a host are passed onto the transmit path.

13. The device of claim 1, where the device includes an embedded client that is a processor for executing firmware instructions.

14. The device of claim 1, further including a buffer connected between the receive path and an embedded client within the device, where the buffer is configured to buffer a frame to be received by the embedded client from the receive path when the embedded client is transmitting a frame to the transmit path.

15. The device of claim 1, where the frame detection logic is configured to identify the loopback frames that are sent from the host device and have a destination within an embedded component within the network without the loopback frames reaching the network.

16. The device of claim 1, further including:

a transmit direct memory access (DMA) engine connected between a host and the transmit path and configured to control traffic on the transmit path from the host; and

a receive direct memory access engine connected between the receive path and the host, and configured to control traffic on the receive path to the host.

17. The device of claim 1, where the device is:

an integrated circuit, an application specific integrated circuit (ASIC), a network interface, or an Ethernet device.

18. A method for transferring network frames, the method comprising:

identifying loopback frames by monitoring network traffic on a transmit path within a network device that provides network connectivity for a host to a network, wherein the network device includes an embedded client and the loopback frames are frames that are addressed to the embedded client; and

re-routing the identified loopback frames sent from the host and addressed to the embedded client from the transmit path to a receive path within the network device wherein the loopback frames are destined at the embedded client without the loopback frames being transmitted back to the host.

19. The method of claim 18, where the loopback frames are identified and rerouted transparently to the host.

20. The method of claim 18, further including:

marking the identified frames with a loopback marking to indicate the frames are loopback frames; and

where rerouting the loopbacks frames occurs based on the loopback marking.

21. The method of claim 20, where the loopback frames are marked by writing a status bit within the loopback frames.

22. The method of claim 18, where the identified frames are identified by scanning network traffic to detect a desktop and mobile architecture for system hardware (DASH) pattern within the frames.

23. The method of claim 18, where the identifying includes identifying a predetermined data pattern within a frame where the predetermined data pattern is associated with a type of an embedded client that is embedded in the network device.

24. The method of claim 18, where the identifying includes identifying a predetermined data pattern within a frame where the predetermined data pattern is associated with the host as being a destination of the frame.

25. The method of claim 18, further including:

transferring frames between the transmit path and the loopback path; and

transferring frames between the loopback path and the receive path.

26. The method of claim 18, further including:

transmitting frames from an embedded client within the network device;

routing the frames transmitted by the embedded client onto the transmit path; and

where the identifying the loopback frames includes identifying loopback frames transmitted by the embedded client and addressed to the host.

27. The method of claim 18, further including buffering a frame to be received by an embedded client from the receive path while a different frame is being transmitted to the transmit path by the embedded client.

28. The method of claim 18, further including identifying loopback frames as frames sent from an embedded client to the host where the embedded client is embedded in the network device.

29. The method of claim 18, including identifying loopback frames transmitted from the host and destined for an embedded client, where the embedded client is embedded in the network device.

30. The method of claim 18, including re-routing loopback frames to be received by an embedded client.

31. The method of claim 18, where identifying the loopback frames is performed in an Ethernet device connects the host to the network.

32. The method of claim 18, further comprising:

transferring network frames between the host and an embedded client within the network device, where the network device provides network communication between the host and the network;

where identifying loopback frames monitors the network traffic transmitted from the host and is destined for the embedded client; and

intercepting the identified loopback frames from the transmit path before the re-routing, the intercepted loopback frames being re-routed to the receive path before the loopback frames reach the network.