US5046182A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Code points for transferring data from a network transmission medium to a station on the network
Assignee: National Semiconductor Corp
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Filing: 1989-12-01
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Granted: 1991-09-03
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Expires: 2009-12-01
Abstract
Abstract Apparatus and methods for encoding information characters received by a station from a transmission medium to generate internal code points for retrieval or retransmission by the station. The encoding provides an internal symbol set that is able to pass complete line state information via its internal code points, thereby eliminating the need for extra signals to indicate the current line state. The code points can also report error situations, such as elasticity buffer errors, and can be accepted by the station's transmitter to be encoded and, after appropriate filtering, repeated onto the transmission medium. The internal code points are optimized so that the code point set minimizes the decoding logic at the receiving end, be it the station's Media Access Control function or its transmitter. Furthermore, internally, the station may make use of the internal code points to synchronize the receiver elasticity buffer.
Inventors
- 👤 James R. Hamstra
- 👤 Ronald S. Perloff
- 👤 Louise Y. Yeung
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:47
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/02; H04L12/12; H04L12/28; H04L12/42; H04L12/427; H04L12/433
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
108 words
Apparatus for transferring an information stream comprising a sequence of multi-bit information characters from a transmission medium to a receiving node, the information stream having one of a plurality of possible line states associated therewith, each multi-bit information character comprising an external code pattern that uniquely identifies the multi-bit information character, the apparatus comprising: (a) means for identifying external code patterns in the information stream; (b) means for converting identified external code patterns to corresponding internal code symbols; (c) means for detecting the line state of the received information stream; and (d) means for adjusting the internal code symbols to convey information corresponding to the detected line state.
Claim 2
Dependent Claim
108 words
Apparatus for transferring an information stream comprising a sequence of multi-bit information characters from a transmission medium to a receiving node, the information stream having one of a plurality of possible line states associated therewith, each multi-bit information character comprising an external code pattern that uniquely identifies the multi-bit information character, the apparatus comprising: (a) means for identifying external code patterns in the information stream; (b) means for converting identified external code patterns to corresponding internal code symbols; (c) means for detecting the line state of the received information stream; and (d) means for adjusting the internal code symbols to convey information corresponding to the detected line state.
Claim 3
Dependent Claim
148 words
In an FDDI token ring network, apparatus for transferring a data stream comprising a sequence of external FDDI symbols received from an FDDI optical fiber transmission medium to a receiving node, the data stream having one of a plurality of possible line states associated therewith, the apparatus comprising: (a) predecoder means for identifying received external FDDI symbols and for converting identified external FDDI symbols to corresponding internal code symbols to provide a sequence of internal code symbols; (b) a line state detector for detecting the line state of the received data stream; (c) means for combining adjacent internal code symbols in the sequence of internal code symbols to provide a sequence of internal code bytes; and (d) post decoder means responsive to the detected line state for adjusting the internal code bytes to provide a sequence of output bytes that convey information corresponding to the detected line state.
Claim 4
Dependent Claim
148 words
In an FDDI token ring network, apparatus for transferring a data stream comprising a sequence of external FDDI symbols received from an FDDI optical fiber transmission medium to a receiving node, the data stream having one of a plurality of possible line states associated therewith, the apparatus comprising: (a) predecoder means for identifying received external FDDI symbols and for converting identified external FDDI symbols to corresponding internal code symbols to provide a sequence of internal code symbols; (b) a line state detector for detecting the line state of the received data stream; (c) means for combining adjacent internal code symbols in the sequence of internal code symbols to provide a sequence of internal code bytes; and (d) post decoder means responsive to the detected line state for adjusting the internal code bytes to provide a sequence of output bytes that convey information corresponding to the detected line state.
Claim 5
Dependent Claim
28 words
Apparatus as in claim 2 wherein each output byte includes a first symbol and a second symbol, the second symbol conveying the identity of the detected line state.
Claim 6
Dependent Claim
46 words
Apparatus as in claim 3 wherein the detected line state is selected from the group consisting of Active Line State (ALS), Idle Line State (ILS), Master Line State (MLS), Halt Line State (HLS), Quiet Line State (QLS), Noise Line State (NLS), and Unknown Line State (ULS).
Claim 7
Dependent Claim
33 words
Apparatus as in claim 4 wherein the second symbol includes a 3-bit binary sequence that identifies the detected line state and a fourth bit that indicates whether the current line state is unknown.
Claim 8
Dependent Claim
27 words
Apparatus as in claim 5 wherein the correspondence between the 3-bit binary sequence and the detected line state is as follows: ALS=000 ILS=001 MLS=100 HLS=101 QLS=110 NLS=111.
Claim 9
Dependent Claim
39 words
Apparatus as in claim 1 and further including means for identifying errors in the received information stream and wherein the means for adjusting includes means for generating internal code points representing the identified errors in the received information stream.
Claim 10
Dependent Claim
14 words
Apparatus as in claim 3 wherein each output byte includes only one control bit.
Claim 11
Dependent Claim
40 words
Apparatus as in claim 3 wherein the post decoder means includes means for adjusting an internal code byte that includes a control symbol and a data symbol to provide a corresponding output byte that includes a special control code point.
Claim 12
Independent Claim
105 words
A method of transferring an information stream comprising a sequence of multi-bit information characters from a transmission medium to a receiving node, the information stream having one of a plurality of possible line states associated therewith, each multi-bit information character comprising an external code pattern than uniquely identifies the multi-bit information character, the method comprising: (a) identifying external code patterns in the information stream; (b) converting identified external code patterns to corresponding internal code symbols; (c) detecting the line state of the received information stream; and (d) adjusting the internal code symbols to internal code points that convey information corresponding to the detected line state.
Claim 13
Independent Claim
105 words
A method of transferring an information stream comprising a sequence of multi-bit information characters from a transmission medium to a receiving node, the information stream having one of a plurality of possible line states associated therewith, each multi-bit information character comprising an external code pattern than uniquely identifies the multi-bit information character, the method comprising: (a) identifying external code patterns in the information stream; (b) converting identified external code patterns to corresponding internal code symbols; (c) detecting the line state of the received information stream; and (d) adjusting the internal code symbols to internal code points that convey information corresponding to the detected line state.
Claim 14
Dependent Claim
128 words
In an FDDI token ring network, a method of transferring a data stream comprising a sequence of external FDDI symbols received from an FDDI optical fiber transmission medium to a receiving node, the data stream having one of a plurality of possible line states associated therewith, the method comprising (a) identifying received external FDDI symbols; (b) converting identified external FDDI symbols to corresponding internal code symbols to provide a sequence of internal code symbols; (c) detecting the line state of the received data stream; (d) combining adjacent internal code symbols in the sequence of internal code symbols to provide a sequence of internal code bytes; and (e) adjusting the internal code bytes to provide a sequence of output bytes that convey information corresponding to the detected line state.
Claim 15
Dependent Claim
128 words
In an FDDI token ring network, a method of transferring a data stream comprising a sequence of external FDDI symbols received from an FDDI optical fiber transmission medium to a receiving node, the data stream having one of a plurality of possible line states associated therewith, the method comprising (a) identifying received external FDDI symbols; (b) converting identified external FDDI symbols to corresponding internal code symbols to provide a sequence of internal code symbols; (c) detecting the line state of the received data stream; (d) combining adjacent internal code symbols in the sequence of internal code symbols to provide a sequence of internal code bytes; and (e) adjusting the internal code bytes to provide a sequence of output bytes that convey information corresponding to the detected line state.
Claim 16
Dependent Claim
15 words
A method as in claim 11 wherein each output byte includes only one control bit.
Claim 17
Dependent Claim
29 words
A method as in claim 11 wherein each output byte includes a first symbol and a second symbol, the second symbol conveying the identity of the detected line state.
Claim 18
Dependent Claim
47 words
A method as in claim 13 wherein the detected line state is selected from the group consisting of Active Line State (ALS), Idle Line State (ILS), Master Line State (MLS), Halt Line State (HLS), Quite Line State (QLS), Noise Line State (NLS) and Unknown Line State (ULS).
Claim 19
Dependent Claim
34 words
A method as in claim 14 wherein the second symbol includes a 13-bit binary sequence that identifies the detected line state and a fourth bit that indicates whether the current line state is unknown.
Claim 20
Dependent Claim
28 words
A method as in claim 15 wherein the correspondence between the 3-bit binary sequence and the detected line state is as follows: ALS=000 ILS=001 MLS=100 HLS=101 QLS=110 NLS=111.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-09-02 | 1995-03-04 | 1995-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-09-02 | 1999-03-04 | 1999-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-09-02 | 2003-03-04 | 2003-09-03 | $7700.00 | Window Closed / Lapsed |