Method of data transmission in a data communication network

• US 20030081609A1
• Filed: 12/06/2002
• Published: 05/01/2003
• Est. Priority Date: 09/11/1998
• Status: Active Grant

• Current Assignee: Rateze Remote Mgmt. L.L.C. (Intellectual Ventures LLC)
• Original Assignee: Teledesic, LLC (Michael J. Larson, MBA)
• Inventors: Boyd, Nathan D.T., Breslow, Noah Joseph, Torluemke, Greg A.
• Granted Patent: US 7,817,639 B2
• Time in Patent Office: Days
• US Class Current: 370/394
• CPC Class Codes: H04B 7/18584 Arrangements for data networking, i.e. for data packet routing, for congestion control data switching networks H04L12/00
• CPC Class Codes: H04L 47/15 in relation to multipoint traffic arrangements for broadcast or multicast in data networks H04L12/18
• CPC Class Codes: H04L 47/70 Admission control; Resource allocation
• CPC Class Codes: H04L 47/824 Applicable to portable or mobile terminals
• CPC Class Codes: H04L 47/826 Involving periods of time

Abstract

A method of data transmission in a data communication network includes negotiating a connection between a source terminal and a destination terminal in the data communication network. During the connection negotiation process, optimal field lengths are determined for recording a source identifier and a sequence number in data packets transmitted in the connection. The source identifier identifies a connection from the source end to the destination end of the data transmission, while the sequence number identifies the relative position of a data packet in a series of data packets transmitted in the connection. The length of the source identifier and sequence number fields may either be calculated or selected from a set of predetermined field length values. Data packets formatted according to different transmission protocols (“secondary data packets”) that are received for transmission through the data communication network are packed into one or more “primary data packets” formatted according to the transmission protocol of the data communication network. In addition to a source identifier and sequence number, the primary data packets include a first packet offset to identify the location of a first new secondary data packet that is packed into the primary data packet. A first packet offset field length is determined during connection negotiation. The data transmission method of the invention includes packing one or more secondary data packets, or a portion thereof, in a primary data packet to fill the primary data packet, thus minimizing unused data bits in the primary data packet. After transmission, the primary data packets are reordered, if necessary, and the secondary data packets are unpacked therefrom.

Claims

1. A method of data transmission in a data communication network, comprising:

(a) transmitting a connection request from a source terminal to a destination terminal in the data communication network, the connection request seeking to establish a connection between the source and destination terminals;

(b) determining at the destination terminal a source identifier field length for recording a source identifier in data packets to be transmitted in the connection, wherein the source identifier identifies the connection;

(c) determining at the destination terminal a sequence number field length for recording a sequence number in data packets to be transmitted in the connection, wherein the sequence number identifies the relative position of a data packet in a series of data packets transmitted in the connection;

(d) transmitting a connection reply from the destination terminal to the source terminal that indicates the determined source identifier field length and sequence number field length; and

(e) transmitting one or more data packets from the source terminal to the destination terminal, the one or more data packets including;

(i) a source identifier recorded in a source identifier field sized according to the determined source identifier field length; and

(ii) a sequence number recorded in a sequence number field sized according to the determined sequence number field length.

2. The method of claim 1, wherein the source identifier field length is determined based on a number of connections being handled by the destination terminal.

3. The method of claim 1, wherein the source identifier field length is determined based on an expected number of connections to be handled by the destination terminal.

4. The method of claim 1, wherein the sequence number field length is determined based on an estimated number of data packets to be transmitted in the connection in a particular time period.

5. The method of claim 4, wherein the connection request indicates an amount of transmission bandwidth to be allocated to the connection, and wherein the estimated number of data packets to be transmitted is derived from the indicated amount of transmission bandwidth.

6. The method of claim 5, wherein the data packets have a “

time to live”

value of a predetermined length, and wherein the estimated number of data packets to be transmitted is calculated by dividing the amount of transmission bandwidth by the packet length of the data packets and multiplying the result by the “

time to live”

value.

7. The method of claim 4, wherein the connection request indicates the estimated number of data packets to be transmitted, and the sequence number field length is determined based on the estimated number of data packets indicated in the connection request.

8. The method of claim 1, wherein the connection request includes a suggested field length for the source identifier field or the sequence number field, and wherein the source identifier field length or sequence number field length is determined based on the field length suggested in the connection request.

9. The method of claim 1, wherein a value representing the determined source identifier field length or sequence number field length is added to the one or more data packets prior to transmission.

10. The method of claim 1, further comprising processing the one or more transmitted data packets at the destination terminal using a process selected in accordance with the source identifier recorded in the data packets.

11. The method of claim 1, further comprising processing the one or more transmitted data packets at the destination terminal in an order derived from the sequence number recorded in the data packets.

12. A method of data transmission in a data communication network, comprising:

(a) selecting a source identifier field length from a set of predetermined source identifier field lengths for recording a source identifier, wherein the source identifier identifies a connection between a source terminal and a destination terminal in the data communication network and is included in data packets transmitted in the connection;

(b) selecting a sequence number field length from a set of predetermined sequence number field lengths for recording a sequence number in data packets transmitted in the connection, wherein the sequence number identifies the relative position of a data packet in a series of data packets transmitted in the connection; and

(c) transmitting one or more data packets from the source terminal to the destination terminal, wherein the one or more data packets include;

(i) a source identifier recorded in a source identifier field sized according to the selected source identifier field length; and

(ii) a sequence number recorded in a sequence number field sized according to the selected sequence number field length.

13. The method of claim 12, wherein the field lengths in the set of predetermined source identifier field lengths are determined based on an expected number of connections to be handled by the destination terminal.

14. The method of claim 12, wherein the source identifier field length is selected based on a characteristic of the connection.

15. The method of claim 14, wherein the characteristic of the connection is the time of day at which the connection is established.

16. The method of claim 12, wherein the field lengths in the set of predetermined sequence number field lengths are determined based on an estimated number of data packets to be transmitted in a connection during a particular time period.

17. The method of claim 12, wherein the sequence number field length is selected based on the identity of the source terminal.

18. A method of data transmission in a data communication network, comprising:

(a) generating a primary data packet formatted for transmission from a source terminal to a destination terminal in the data communication network, the primary data packet having a header and a payload, the header including a sequence number field and a first packet offset field, and the payload including one or more secondary data packets packed therein;

(b) recording a sequence number in the sequence number field, the sequence number identifying the relative position of the primary data packet in a series of primary data packets;

(c) recording a first packet offset value in the first packet offset field, the first packet offset value identifying the location of a first new secondary data packet that is packed in the primary data packet payload;

(d) transmitting the primary data packet from the source terminal to the destination terminal; and

(e) at the destination terminal, unpacking the one or more secondary data packets from the primary data packet payload, wherein the first new secondary data packet in the primary data packet payload is located for unpacking by reference to the first packet offset value.

19. The method of claim 18, wherein two or more primary data packets are transmitted through the data communication network, and wherein after the two or more primary data packets are received at the destination terminal, the two or more primary data packets are reordered according to their respective sequence numbers.

20. The method of claim 18, wherein the first new secondary data packet is located for unpacking by using the first packet offset value in an equation to produce a value identifying the location in the primary data packet payload.

21. The method of claim 18, wherein unpacking the one or more secondary data packets is performed even if the destination terminal has not yet received one or more prior primary data packets that were previously generated and transmitted by the source terminal.

22. A method of data transmission from a source ground terminal to a destination ground terminal in a LEO satellite data communication network, the method comprising:

(a) generating a primary data packet having a header and a payload;

(b) packing one or more secondary data packets in the payload of the primary data packet until the number of bits remaining available in the primary data packet payload is less than the number of bits in a secondary data packet not yet packed;

(c) dividing the secondary data packet not yet packed to define a first portion and a second portion, wherein the number of bits in the first portion equals the number of bits remaining available in the primary data packet payload;

(d) packing the first portion in the primary data packet payload;

(e) generating one or more additional primary data packets;

(f) packing the second portion in the payload of the one or more additional primary data packets, dividing the second portion as necessary into additional portions equaling the length of the payload of the one or more additional primary data packets; and

(g) transmitting the primary data packets from the source ground terminal to the destination ground terminal via one or more satellites in the LEO satellite data communication network.

23. The method of claim 22, further comprising:

(a) unpacking the one or more secondary data packets from the primary data packet payload; and

(b) if a portion of a secondary data packet was packed in the primary data packet payload, then unpacking the portion from the primary data packet payload.

24. The method of claim 23, further comprising retaining the unpacked portion of a secondary data packet in a memory with a timer, and deleting the unpacked portion from the memory when a period of time measured by the timer expires.

25. The method of claim 23, further comprising appending the unpacked portion of a secondary data packet to another previously unpacked portion of the same secondary data packet.

26. A method of data transmission in a data communication network, comprising:

(a) transmitting a connection request from a source terminal to a destination terminal in the data communication network, the source terminal having a network identifier for identifying the source terminal in the data communication network, the connection request seeking to establish a connection between the source terminal and the destination terminal for a data transmission that spans a plurality of transmission links;

(b) determining at the destination terminal a source identifier for identifying the connection, wherein the number of bits in the source identifier is fewer than the number of bits in the network identifier of the source terminal;

(c) transmitting a connection reply from the destination terminal to the source terminal, wherein the connection reply includes the determined source identifier; and

(d) transmitting one or more data packets from the source terminal to the destination terminal, wherein the data packets include the determined source identifier and do not include the source terminal'"'"'s network identifier.

27. A method of data transmission in a data communication network, comprising:

(a) generating a primary data packet for transmission from a source terminal to a destination terminal in the data communication network, the primary data packet including one or more secondary data packets packed therein, the primary data packet further including a first packet offset field having a predetermined field length, the first packet offset field for recording a first packet offset value that identifies the location of a first new secondary data packet that is packed in the primary data packet;

(b) recording a first packet offset value in the first packet offset field, the length of the first packet offset value equaling the predetermined first packet offset field length;

(c) transmitting the primary data packet from the source terminal to the destination terminal; and

(d) at the destination terminal, unpacking the one or more secondary data packets from the primary data packet.

28. The method of claim 27, wherein the predetermined first packet offset field length is determined by the destination terminal during a connection negotiation conducted between the source terminal and the destination terminal prior to the generating and transmitting of the primary data packet.

29. The method of claim 28, wherein the primary data packet further includes one or more other data fields and the predetermined first packet offset field length is determined based on the length of the one or more other data fields.

30. The method of claim 29, wherein the one or more other data fields includes a source identifier field and a sequence number field.

31. The method of claim 27, wherein the one or more secondary data packets are packed at selected intervals in the primary data packet and the number of bits in the primary data packet between the selected intervals depends on the predetermined first packet offset field length.