Fibre channel frame batching for IP transmission
View Patent ↗A storage router and related method are presented for combining multiple Fibre Channel frames together into a single IP datagram for tunneling transmission over an Internet protocol network. The storage router operates by storing incoming Fibre Channel frames in a Fibre Channel frame buffer. When there is sufficient data in the buffer, multiple Fibre Channel frames are taken from the buffer and combined into a single IP datagram. The number of Fibre Channel frames to be combined can be established through a variety of tests, including total bytes of data, number of frames, or through a time-out mechanism. The network layer then fragments the datagram into data link level frames, such as 1500 byte Ethernet frames. When the IP datagram arrives at the final destination, the segmented IP datagram is reconstructed, and the multiple Fibre Channel frames are extracted from the IP datagram and passed on to the recipient Fibre Channel network.
1. A method for transmitting Fibre Channel frames from a Fibre Channel network at a first location to a Fibre Channel network at a second location over an Internet protocol network comprising the steps of:
a) receiving a plurality of Fibre Channel frames from the Fibre Channel network at the first location;
b) combining the plurality of Fibre Channel frames into a single datagram;
c) adding transport and IP headers to the single datagram;
d) fragmenting the single datagram into a plurality of data link level frames;
e) transmitting the data link level frames from the first location over the Internet protocol network;
f) receiving the data link level frames from the Internet protocol network at the second location;
g) combining the data link level frames back into the single datagram;
h) extracting the plurality of Fibre Channel frames from the single datagram; and
i) transmitting the plurality of Fibre Channel frames over the Fibre Channel network at the second location.
2. The method of claim 1 , wherein step a) further comprises the sub-step of storing the plurality of Fibre Channel frames on a Fibre Channel frame buffer.
3. The method of claim 1 , wherein step b) further comprises:
i) tracking the number of Fibre Channel frames received since the last datagram was created;
ii) combining the Fibre Channel frames received since the last datagram was created when the tracked number of Fibre Channel frames exceeds a frames limit value.
4. The method of claim 3 , wherein the frames limit value is set heuristically to maximize data throughput over the Internet protocol network.
5. The method of claim 3 , wherein the frames limit value is set heuristically to balance maximizing data throughput over the Internet protocol network without significantly increasing data latency.
6. The method of claim 1 , wherein step b) further comprises:
i) tracking the amount of data in the Fibre Channel frames received since the last datagram was created;
ii) combining the Fibre Channel frames received since the last datagram was created when the tracked amount of data exceeds a data limit value.
7. The method of claim 1 , wherein step b) further comprises:
i) tracking the amount of time since the last datagram was created;
ii) combining the Fibre Channel frames received since the last datagram was created when the tracked amount of time exceeds a time limit value.
8. A storage router comprising:
a) a Fibre Channel interface that receives Fibre Channel frames from a Fibre Channel network;
b) a Fibre Channel frame buffer memory that stores Fibre Channel frames received by the Fibre Channel interface;
c) a network interface in communication with the Fibre Channel frame buffer memory and with an Internet protocol network;
d) a processor that causes a single datagram to be formed from a plurality of received Fibre Channel frames stored on the Fibre Channel frame buffer memory;
e) at least one networking object that adds transport and IP headers to the single datagram and fragments the datagram into a plurality of data link frames appropriate for transmission over the Internet protocol network via the network interface.
9. The storage router of claim 8 , wherein the Internet protocol network has a maximum transmission unit (MTU) value, and the Fibre Channel frames have a maximum size value that is greater than the MTU value.
10. The storage router of claim 9 , wherein the plurality of received Fibre Channel frames are fewer in number than the plurality of data link frames.
11. The storage router of claim 8 , wherein the Internet protocol network has a maximum transmission unit (MTU) value, and the Fibre Channel frames have a maximum size value that is smaller than the MTU value.
12. The storage router of claim 9 , wherein the plurality of received Fibre Channel frames are greater in number than the plurality of data link frames.