Data representation protocol for communications between different networks

• US 5,175,817 A
• Filed: 11/20/1989
• Issued: 12/29/1992
• Est. Priority Date: 11/20/1989
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Digital Equipment Corporation (HP Inc.)
• Inventors: Kaycee, Mahendra J., Adams, Samuel T., Heffler, Michael J.
• Primary Examiner(s): Kriess, Kevin A.
• Application Number:
  US07/439,239
• Time in Patent Office: 1,135 Days
• Field of Search: 364/200, 364/900, 395/200, 395/500
• US Class Current: 709/236
• CPC Class Codes: H04L 49/90 Buffering arrangements
• CPC Class Codes: H04L 69/08 Protocols for interworking; Protocol conversion
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers

Abstract

A data representation and protocol are provided to interface two networks. A plurality of information units to be transmitted from one network to another are formatted into a variable size block in accordance with the protocol. Each block contains a header field storing a total information unit count and a control information unit count. The remainder of the block stores the actual information itself, both control and data, in consecutive byte locations, with the actual control information located at the end of the block. The block can then be sent to another network for processing. A device in the other network need only reference the block header to determine whether the information contained in the block is control or data. This speeds the processing of large quantities of either all data information and/or control information.

Claims

1. A method of transmitting data and control information between two networks that use different data representation formats, the method comprising the steps of:

A) generating information units in one of the networks that includes control information units and data information units;

B) forming the information units into a block in the order in which said information units are generated;

C) determining for each information unit generated whether said each information unit is a control information unit or a data information unit;

D) ending forming the block at a control information unit when a block sequence has a control information unit followed by a data information unit; and

E) sending the block to the other of said networks.

2. The method according to claim 1 further comprising the step of:

F) repeating steps A), B), C), D), and E) for all information units to be transmitted.

3. The method according to claim 2 wherein the step of forming the information units further comprises the steps of:

1) forming a header field for said block; and

2) accounting in the header field for a total number of each type of information unit contained in the block.

4. The method according to claim 3 wherein the step of accounting further comprises the steps of:

a) storing a count of a total number of information units in the block; and

b) storing a count of a total number of control information units in the block.

5. The method according to claim 4 further comprising the steps of:

G) receiving the block in the other of said networks;

H) comparing, in the other of said networks, the count of the total number of information units with the count of the total number of control information units to determine a total number of data information units in the block.

6. The method according to claim 3 wherein the one network is an n-bit network and the other network is an m-bit network, m being equal to n+1, said information units forming the block each having n-bits, further comprising the steps of:

G) receiving the block in the m-bit network;

H) checking the header field to determine, in the order in which said information units are generated, whether each information unit is a data information unit or a control information unit;

I) appending an m^th bit, having a first value, to said n-bit information units that are data information units;

J) appending an m^th bit, having a second value, to said n-bit information units that are control information units; and

K) providing a serial stream of the appended information units for the m-bit network.

7. In a system including a plurality of clients of one network, with a first network using a first data representation format, coupled to a server which communicates with second network, the second network using a second data representation format, a method of transmitting data and control information between the first network and the second network, the method comprising the steps of:

A) generating information units from the first network that includes control information units and data information units;

B) forming the information units into a block in the order in which said information units are generated;

C) determining for each information unit generated whether each information unit is a control information unit or a data information unit;

D) ending formation of a block with a control information unit when a block sequence has a control information unit followed by a data information unit; and

E) sending the block to the second networks.

8. The method according to claim 7 wherein the step of forming the information units is carried out in the server.

9. The method according to claim 7 wherein the step of forming the information units is carried out in one of the plurality of clients.

10. The method according to claim 7 wherein one of said two networks is a single computer device.

11. A computer system, comprising:

an m-bit network;

an n-bit network including at least one device;

a server coupling the m-bit network to the n-bit network, with the server further including;

a memory;

means in the memory for receiving and storing information units from the m-bit network, said information units including control information units and data information units;

means for forming the information units into a block in the order in which said information units are received in the memory;

means for determining whether each information unit received is a control information unit or a data information unit;

means for ending the formation of said block with a control information unit when a sequence of a control information unit followed by a data unit is detected; and

means for ending the block to the n-bit network.

12. The system according to claim 11 wherein the means for forming the information units comprises means for forming a header field for said block.

13. A system according to claim 12 further comprising:

means for receiving the block in the n-bit network;

first means for counting a total number of information units in the block;

second means for counting a total number of control information units in the block; and

means for comparing the total number of information units with the total number of control information units to determine a total number of data information units in the block.

14. The system according to claim 13 wherein one of said m-bit or n-bit networks is a single computer.

15. A server for interfacing between an m-bit network and an n-bit network, comprising:

a memory;

means in the memory for receiving and storing information units from the m-bit network, said information units including control information units and data information units;

means for forming the information units into a block in the order in which the information units are received in the memory;

means for determining whether each information unit received is a control information unit or a data information unit;

means for determining a sequence of a control information unit followed by a data information unit; and

means for ending the formation of said block with said preceding control information unit.

16. The server according to claim 15 wherein the means for forming the information units comprises means for forming a header field for said block.