Intelligent midspan PoE injector
Adding a separate communication link between an intelligent midspan Power Source Equipment (PSE) device and a network device (or between the midspan PSE device and a powered device (PD)) enables data communication from the network device to the intelligent midspan PSE device. The communication link provides a communication channel that the intelligent midspan PSE device may use to perform additional functions such as reallocating power, budgeting power, enabling or disabling Power over Ethernet (PoE) for a particular PD, prioritizing PoE management, and the like.
1. A midspan device, comprising:
a first Ethernet port configured to couple to a first Ethernet cable, the first Ethernet cable coupling the midspan device to a network device, wherein the network device transmits only data to the midspan device;
a second Ethernet port configured to couple to a second Ethernet cable, the second Ethernet cable coupling the midspan device to a powered device;
a communication port configured to communicatively couple the midspan device to at least one of the network device and the powered device; and
a power supply configured to provide power via the second Ethernet port to the powered device, the power supply configured to receive a request via the communication port and allocate power to the powered device based on a specified power level in the request, wherein the request is received from one of the network device and the powered device.
2. The midspan device of claim 1 , wherein the communication port is a different port from the first and second Ethernet ports.
3. The midspan device of claim 1 , wherein the network device routes data communications to the powered device, and from the powered device, in a network.
4. The midspan device of claim 1 , wherein the communication port is coupled to a wire, and wherein the communication port is one of: an I 2 C port, a RS-232 serial port, and a third Ethernet port.
5. The midspan device of claim 1 , wherein the communication port is communicatively coupled to the network device, wherein the network device transmits the request to change a power allocated by a power allocator to the powered device.
6. The midspan device of claim 5 , wherein, the request is transmitted in response to the network device receiving a power change message from the powered device via the first and second Ethernet cables, the power change message specifying a requested power allocation for the powered device.
7. The midspan device of claim 1 , wherein the network device transmits the request to change a power allocated to the powered device based on a time of day.
8. A method, comprising:
receiving a data communication from a network device via a first Ethernet cable coupled to a first Ethernet port of a midspan device, wherein the network device transmits only data to the midspan device;
forwarding the data communication to a powered device using a second Ethernet cable coupled to a second Ethernet port of the midspan device;
providing power to the powered device via the second Ethernet cable;
receiving a request via a communication port of the midspan device, the request specifying a change to a power allocated to the powered device, wherein the communication port communicatively couples the midspan device to at least one of the network device and the powered device; and
changing the power allocated to the powered device based on a specified power level in the request, wherein the request is received from one of the network device and the powered device.
9. The method of claim 8 , wherein the communication port is a different port from the first and second Ethernet ports.
10. The method of claim 8 , wherein the network device routes data communications to the powered device, and from the powered device, in a network.
11. The method of claim 8 , wherein the communication port is coupled to a wire, and wherein the communication port is one of: an I 2 C port, a RS-232 serial port, and a third Ethernet port.
12. The method of claim 8 , wherein the communication port is communicatively coupled to the network device, wherein the midspan device receives the request to change a power allocated from the network device.
13. The method of claim 12 , wherein, the request is transmitted in response to the network device receiving a communication from the powered device via the first and second Ethernet cables, the communication specifying a requested power allocation for the powered device.
14. The method of claim 12 , further comprising:
transmitting a confirmation via the communication port to the network device, the confirmation specifying the power allocated to the powered device based on the received request; and
in response to receiving the confirmation, forwarding the confirmation to the powered device using the first and second Ethernet cables.
15. The method of claim 8 , wherein the network device does not contain power source equipment for providing power over Ethernet.
16. A system, comprising:
a powered device;
a network device; and
a midspan device comprising:
a first Ethernet port configured to couple to a first Ethernet cable, the first Ethernet cable coupling the midspan device to the network device, wherein the network device transmits only data to the midspan device;
a second Ethernet port configured to couple to a second Ethernet cable, the second Ethernet cable coupling the midspan device to the powered device;
a communication port configured to couple to a wire, the wire coupling the midspan device to at least one of the network device and the powered device; and
a power supply configured to provide power via the second Ethernet port to the powered device, the power supply configured to receive a request via the communication port and allocate power to the powered device based on a specified power level in the request, wherein the request is received from one of the network device and the powered device.
17. The system of claim 16 , wherein the network device further comprises a Power over Ethernet module configured to receive power messages from the powered device using a first communication protocol and transmitting the request to the midspan device using a different, second communication protocol.
18. The system of claim 16 , wherein the network device further comprises a Power over Ethernet module that transmits the request to the midspan device based on the time of day.
19. The system of claim 16 , wherein the midspan device is configured to, after allocating power to the powered device based on the power level in the request, transmit a confirmation message to one of the network device and powered device.
20. The system of claim 16 , wherein the network device routes data communications to the powered device, and from the powered device, in a network.
21. The system of claim 16 , wherein the communication port is a different port from the first and second Ethernet ports.
22. The system of claim 16 , wherein the network device does not contain power source equipment for providing power over Ethernet.
23. The midspan device of claim 1 , further comprising logic configured to directly communicate with at least one of the network device and the powered device to negotiate power allocated for the powered device.