Method and apparatus for packetizing data into a data stream

• US 6,275,505 B1
• Filed: 05/30/1998
• Issued: 08/14/2001
• Est. Priority Date: 05/30/1998
• Status: Expired due to Term

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Alcatel Canada Inc. (Nokia Corporation)
• Inventors: Smail, J. Morgan, Patoine, Michel J. P., O'Loughlin, Gareth P.
• Primary Examiner(s): Marcelo, Melvin
• Assistant Examiner(s): TRINH, DUNG N
• Application Number:
  US09/087,840
• Time in Patent Office: 1,172 Days
• Field of Search: 370/465, 370/471, 370/473, 370/474, 370/505, 370/509, 370/514
• US Class Current: 370/473
• CPC Class Codes: H04J 3/047 Distributors with transistors or integrated circuits
• CPC Class Codes: H04J 3/1641 Hierarchical systems
• CPC Class Codes: H04L 12/6418 Hybrid transport

Abstract

A method and apparatus for packetizing data include processing that begins by determining the bit time occurrence for retrieval of at least one bit of a portion of a data word, which is stored in local memory. Next, the processing determines the status of the data word based on the bit time occurrence for retrieval of the bit. Next, the bit is retrieved from local memory based on the status of the data word. Having retrieved the bit, the status of the data word is updated based on the bit time occurrence of the at least one bit and the data word. Next, the processing applies a data packetizing protocol to the at least one retrieved bit based on the status of the data word to construct a data packet corresponding to the data word.

Claims

1. A method for packetizing data, the method comprises the steps of:

a) determining bit-time occurrence for retrieval of at least one bit of at least a portion of a data word;

b) determining status of the data word based on the bit-time occurrence;

c) retrieving, from local memory, the at least one bit based on the status of the data word to produce at least one retrieved bit;

d) updating status of the data word based on the bit-time occurrence of the at least one bit and the data word to produce updated status of the data word; and

e) applying a data packetizing protocol to the at least one retrieved bit based on the status of the data word to construct a data packet corresponding to the data word.

2. The method of claim 1, wherein step (e) further comprises at least one of:

outputting the at least one retrieved bit;

generating a stuffing bit and outputting the stuffing bit;

outputting at least one error checking bit; and

outputting at least one flag bit.

3. The method of claim 1, wherein step (e) further comprises inserting at least one abort bit in the at least one retrieved bit position when an underflow condition is detected.

4. The method of claim 1, wherein step (c) further comprises:

determining at least one data section of the local memory based on a logical channel, wherein the local memory includes a plurality of data sections and associated status sections, and wherein the data packet is conveyed via the logical channel; and

retrieving the at least one bit from a given location of the at least one data section.

5. The method of claim 4 further comprises storing the updated status in the associated status section corresponding to the at least one data section.

6. The method of claim 1, wherein the status of the data word comprises at least one of:

current status of the data word, history status of the data word, mapping information of a logical channel to local memory, local memory context information that contains addressing information, current stored word length, and link list information.

7. The method of claim 1, wherein step (e) further comprises:

determining that the at least one bit is affiliated with an unassigned logical channel; and

outputting a null bit in place of the at least one bit.

8. A method for packetizing data, the method comprises the steps of:

a) storing at least a portion of the data word in at least one data storage section of a plurality of data storage sections of local memory;

on a bit by bit basis,

b) obtaining data mapping information that corresponds the data word to the at least one data storage section and time positioning data;

c) obtaining memory context information based on at least a portion of the data mapping information, wherein the memory context information contains current bit retrieval status of the at least a portion of the data word; and

d) processing a bit of the at least a portion of the data word as at least one of;

data and data packetizing protocol information based on at least one of;

time occurrence of the bit, the data mapping information, and the memory context information.

9. The method of claim 8 further comprises, prior to step (a), determining at least a portion of a data word is available for packetizing.

10. The method of claim 9 further comprises:

determining that the data word is available for transporting; and

determining an allocated portion of the local memory has capacity to store the at least a portion of the data word.

11. The method of claim 8, wherein step (b) further comprises:

determining a logical channel affiliation of the bit based on time occurrence for retrieval of the bit and the time positioning data; and

identifying the at least one data storage section based on the logical channel affiliation.

12. The method of claim 8, wherein the current bit retrieval status comprises at least one of:

channel segment rate, addressing mode, valid data, linked memory segments, and data storage section fill status.

13. The method of claim 8, wherein step (d) further comprises:

determining logical channel affiliation of the bit based on time occurrence for retrieval of the bit and the time positioning data;

obtaining the memory context information specific to the logical channel to obtain specific memory context information; and

determining whether the bit corresponds to data and data packetizing protocol information based on the specific memory context information and the data content of the bit.

14. The method of claim 13 further comprises:

interpreting the specific memory context information to identify that outgoing data is valid;

comparing the data content of the bit and at least a portion of previously outputted bits of the data word with an end of data packet flag; and

outputting the bit as data when the comparing to the end of data word flag was favorable.

15. The method of claim 14 further comprises:

determining that the bit is packet protocol information when the comparing to the end of data word flag was unfavorable; and

updating the specific memory context information to indicate that the data word has been outputted when the comparing to the end of data packet flag was unfavorable.

16. The method of claim 14 further comprises outputting a stuffing bit as the data when the data is valid and a pattern of data matches a packetizing protocol pattern.

17. The method of claim 13 further comprises:

comparing the data content of the bit and at least a portion of previously outputted bits associated with the logical channel with a start of data packet flag;

determining that the bit is packet protocol information when the comparing to the end of data packet flag was favorable;

outputting the bit as packet protocol information when the comparing to the start of data packet flag was favorable; and

updating the specific memory context information to indicate that the data packet is beginning to be outputted when the comparing to the start of data packet flag was favorable.

18. The method of claim 13, further comprises determining the bit is frame delineation data based on the time occurrence for the retrieval of the bit and the time positioning data.

19. A data packetizing module comprises:

a processing module;

local memory; and

memory operably coupled to the processing module, wherein the memory includes operating instructions that cause the processing module to (a) determine bit-time occurrence for retrieval of at least one bit of at least a portion of a data word;

(b) determine status of the data word based on the bit-time occurrence;

(c) retrieve, from the local memory, the at least one bit based on the status of the data word to produce at least one retrieved bit;

(d) update status of the data word based on the bit-time occurrence of the at least one bit and the data word to produce updated status of the data word; and

(e) apply a data packetizing protocol to the at least one retrieved bit based on the status of the data word to construct a data packet corresponding to the data word.

20. The data packetizing module of claim 19, wherein applying the data packetizing

protocol includes at least one of:

outputting the at least one retrieved bit;

generating a stuffing bit and outputting the stuffing bit;

outputting at least one error checking bit; and

outputting at least one flag bit.

21. The data packetizing module of claim 19, wherein applying the data packetizing protocol includes inserting at least one abort bit in the at least one retrieved bit position when an underflow condition is detected.

22. The data packetizing module of claim 19, wherein the memory further comprises operating instructions that cause the processing module to:

determine at least one data section of the local memory based on a logical channel, wherein the data packet is conveyed via the logical channel; and

retrieve the at least one bit from a given location of the at least one data section.

23. The data packetizing module of claim 22, wherein the memory further comprises operating instructions that cause the processing module to store the updated status in the associated status section of the at least one data section.

24. The data packetizing module of claim 19, wherein the memory further comprises operating instructions that cause the processing module to:

determine that the at least one bit is affiliated with an unassigned logical channel; and

output a null bit in place of the at least one bit.

25. A data packetizing module comprises:

a processing module;

local memory; and

memory operably coupled to the processing module, wherein the memory includes operating instructions that cause the processing module to (a) store at least a portion of the data word in at least one data storage section of a plurality of data storage sections of the local memory; and

, on a bit by bit basis, (b) obtain data mapping information that corresponds the data word to the at least one data storage section and time positioning data;

(c) obtain memory context information based on at least a portion of the data mapping information, wherein the memory context information contains current bit retrieval status of the at least a portion of the data word; and

(d) process a bit of the at least a portion of the data word as at least one of;

data and data packetizing protocol information based on at least one of;

time occurrence of the bit, the data mapping information, and the memory context information.

26. The data packetizing module of claim 25, wherein the memory further comprises operating instructions that cause the processing module to:

determine a logical channel affiliation of the bit based on time occurrence for retrieval of the bit and the time positioning data; and

identify the at least one data storage section based on the logical channel affiliation.

27. The data packetizing module of claim 25, wherein the memory further comprises operating instructions that cause the processing module to:

determine logical channel affiliation of the bit based on time occurrence for retrieval of the bit and the time positioning data;

obtain the memory context information specific to the logical channel to obtain specific memory context information; and

determine whether the bit corresponds to data, packetizing protocol information, or frame delineation data based on the specific memory context information and the data content of the bit.

28. The data packetizing module of claim 27, wherein the memory further comprises operating instructions that cause the processing module to:

interpret the specific memory context information to identify that outgoing data is valid;

compare the data content of the bit and at least a portion of previously outputted bits of the data word with an end of data packet flag; and

output the bit as data when the comparing to the end of data word flag was favorable.

29. The data packetizing module of claim 28, wherein the memory further comprises operating instructions that cause the processing module to:

determine that the bit is packet protocol information when the comparing to the end of data word flag was unfavorable; and

update the specific memory context information to indicate that the data word has been outputted when the comparing to the end of data packet flag was unfavorable.

30. The data packetizing module of claim 28, wherein the memory further comprises operating instructions that cause the processing module to output a stuffing bit as the data when the data is valid and a pattern of data matches a packetizing protocol pattern.

31. The data packetizing module of claim 28, wherein the memory further comprises operating instructions that cause the processing module to:

compare the data content of the bit and at least a portion of previously outputted bits associated with the logical channel with a start of data packet flag;

determine that the bit is packet protocol information when the comparing to the end of data packet flag was favorable;

output the bit as packet protocol information when the comparing to the start of data packet flag was favorable; and

update the specific memory context information to indicate that the data packet is beginning to be outputted when the comparing to the start of data packet flag was favorable.

32. The data packetizing module of claim 28, wherein the memory further comprises operating instructions that cause the processing module to determine the bit is frame delineation data based on the time occurrence for the retrieval of the bit and the time positioning data.