Packet characterization using code vectors

• US 5,825,774 A
• Filed: 07/12/1995
• Issued: 10/20/1998
• Est. Priority Date: 07/12/1995
• Status: Expired due to Term

• Current Assignee: Palo Alto Networks Incorporated
• Original Assignee: 3Com Corporation (HP Inc.)
• Inventors: Flanders, John A., Ready, David C., Van Seters, Stephen L.
• Primary Examiner(s): Safourek, Benedict V.
• Application Number:
  US08/501,484
• Time in Patent Office: 1,196 Days
• Field of Search: 395/200.13, 395/200.19, 395/309, 370/85.3, 370/85.13, 370/85.14, 370/94.1, 370/60, 370/389.445, 370/401, 370/402, 370/403, 370/906, 370/910, 370/911
• US Class Current: 370/401
• CPC Class Codes: H04L 49/90 Buffering arrangements
• CPC Class Codes: H04L 49/9063 Intermediate storage in different physical parts of a node or terminal
• CPC Class Codes: H04L 69/08 Protocols for interworking; Protocol conversion
• CPC Class Codes: H04L 69/12 Protocol engines
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/161 Implementation details of TCP/IP or UDP/IP stack architecture; Specification of modified or new header fields
• CPC Class Codes: Y10S 370/906 Fiber data distribution interface, FDDI
• CPC Class Codes: Y10S 370/91 Carrier sense multiple access, e.g. ethernet, 10base-t
• CPC Class Codes: Y10S 370/911 Bridge, e.g. brouter, bus extender

Abstract

A method and apparatus for increasing the throughput of a communications internetworking device. The method involves the generating, by internetworking device hardware, of a predetermined code vector in response to the current state of the communications internetworking device and information contained in a data packet received by the internetworking device. In response to the hardware generated predetermined code vector, a predetermined software routine is executed by a microprocessor in the internetworking device which controls how the data packet is to be transmitted to its destination. By using hardware to generate the code vector, time is saved over having software determine how the internetworking device is to handle the data packet.

Claims

1. An internetworking device having a plurality of states and comprising:

at least one ethernet MAC;

at least one FDDI MAC;

a frame processor; and

a code vector generator in electrical communication with said frame processor, said at least one FDDI MAC, and said at least one ethernet MAC,

said code vector generator generating in hardware a code vector in response to a data packet arriving at one of said at least one ethernet MAC and at least one FDDI MAC and in response to a present state of said internetworking device,

said frame processor executing predetermined code in response to said code vector generated by said code vector generator to transmit said data packet from said internetworking device.

2. The internetworking device of claim 1 wherein said internetworking device further comprises a frame processor memory in electrical communication with said frame processor and storing said predetermined code.

3. The internetworking device of claim 1 further wherein said code vector generator is a portion of a receive buffer state machine, said receive buffer state machine further comprising a plurality of registers, each of said plurality of registers holding data partially determinative of said present state of said internetworking device.

4. The internetworking device of claim 1 further comprising a monitor translation code logic circuit, said monitor translation code logic circuit in electrical communication with said code vector generator and said frame processor, said monitor translation code logic circuit generating in hardware a monitor code in response to said code vector generated by said code vector generator and said present state of said internetworking device, said frame processor executing predetermined code in response to monitor code generated by said monitor translation code logic circuit to transmit said data packet from said internetworking device to a remote monitor.

5. A method of transmitting a data packet from a internetworking device having a plurality of states and comprising at least one ethernet MAC, at least one FDDI MAC, a frame processor and a hardware code vector generator in electrical communication with said frame processor, said at least one FDDI MAC, and said at least one ethernet MAC, said method comprising the steps of:

receiving said data packet at one of said at least one ethernet MAC and at least one FDDI MAC;

generating in said hardware code vector generator, a code vector in response to said data packet arriving at one of said at least one ethernet MAC and at least one FDDI MAC and in response to a present state of said internetworking device; and

executing, with said frame processor, predetermined code in response to said code vector generated by said code vector generator to transmit said packet from said internetworking device.

6. The method of claim 5, wherein said internetworking device further comprises a monitor translation code logic circuit in electrical communication with said code vector generator and said frame processor, said method further comprising the steps of:

generating, in said hardware of said monitor translation code logic circuit, a monitor code in response to said code vector generated by said code vector generator and said present state of said internetworking device, and

executing, by said frame processor, predetermined code in response to monitor code generated by said monitor translation code logic circuit to transmit said data packet from said internetworking device to a remote monitor.