Patent US5878041A successfully refreshed from Google Patents.
US5878041A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Error handling in transmission of data that cannot be retransmitted
Assignee: Fujitsu Ltd
•
Filing: 1996-09-11
•
Granted: 1999-03-02
•
Expires: 2016-09-11
Abstract
Abstract CPCS-UU in the CPCS-PDU trailer defined by the AAL Type 5 in an ATM network is used as a sequence number for error handling. CPCS-UU in the CPCS-PDU trailer is used as a sequence number of an MPEG-2 transport stream packet contained in CPCS-PDU; by monitoring the number of packets, and based on the check results of CRC-32, LI, and cell count, error handling is performed at the receiving end, and for corrupted packets, null packets are inserted in place of the corrupted packets.
Inventors
- 👤 Masayuki Yamanaka
- 👤 Tetsuo Tachibana
- 👤 Tatsuru Nakagaki
- 👤 Kenji Nemoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:03
CPC Classifications
H; H04; H04L; H04L1/00; H04L1/0078; H04L1/0083; H04L49/00; H04L49/30; H04L49/3081; H04N; H04N19/00; H04N19/85; H04N19/89; H04N21/00; H04N21/20; H04N21/23; H04N21/238; H04N21/2381; H04N21/60; H04N21/63; H04N21/643; H04N21/64307; H04Q; H04Q11/00; H04Q11/04; H04Q11/0428; H04Q11/0478; H04L12/00; H04L12/54; H04L12/56; H04L12/5601; H04L2012/5638; H04L2012/564; H04L2012/5642; H04L2012/5646; H04L2012/5647; H04L2012/5652; H04L2012/5653; H04L2012/5658
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
99 words
An error-handling method comprising the steps of: receiving a data unit in which at least a packet is contained as payload, and to which a sequence number associated with the contained packet is appended; detecting loss of a packet that should be extracted from the data unit by examining the sequence number appended to the received data unit; and inserting as many null packets as lost packets between packets extracted from data units before and after the data unit when packet loss is detected, wherein the data unit is segmented into a plurality of cells that are asynchronously transferred.
Claim 2
Dependent Claim
99 words
An error-handling method comprising the steps of: receiving a data unit in which at least a packet is contained as payload, and to which a sequence number associated with the contained packet is appended; detecting loss of a packet that should be extracted from the data unit by examining the sequence number appended to the received data unit; and inserting as many null packets as lost packets between packets extracted from data units before and after the data unit when packet loss is detected, wherein the data unit is segmented into a plurality of cells that are asynchronously transferred.
Claim 3
Dependent Claim
44 words
A method according to claim 1, wherein the step of detecting packet loss includes the substeps of: determining whether the data unit has been received correctly; and examining the sequence number only when it is determined that the data unit has been received correctly.
Claim 4
Dependent Claim
38 words
A method according to claim 2 wherein the substep of determining whether the data unit has been received correctly includes the substep of determining whether the cells carried in the received data unit have each been received correctly.
Claim 5
Dependent Claim
53 words
A method according to claim 1, wherein the step of inserting null packets includes the substeps of: storing the packet extracted from the received data unit into a buffer; and selecting one of the packet stored in the buffer and a null packet, depending on whether packet loss has been detected or not.
Claim 6
Dependent Claim
34 words
A method according to claim 1, wherein the data unit is a CPCS-PDU defined at the ATM Adaptation Layer Type 5, and the sequence number is stored in a CPCS-UU field in the CPCS-PDU.
Claim 7
Dependent Claim
15 words
A method according to claim 5, wherein the packet is an MPEG-2 transport stream packet.
Claim 8
Dependent Claim
105 words
An error-handling apparatus comprising: a circuit for receiving a data unit in which at least a packet is contained as payload, and to which a sequence number associated with the contained packet is appended: a circuit for, by examining the sequence number appended to the received data unit, detecting loss of a packet that should be extracted from the data unit; and a circuit for, when packet loss is detected, inserting as many null packets as lost packets between packets extracted from data units before and after the data unit, wherein the data unit is segmented into a plurality of cells that are asynchronously transferred.
Claim 9
Dependent Claim
105 words
An error-handling apparatus comprising: a circuit for receiving a data unit in which at least a packet is contained as payload, and to which a sequence number associated with the contained packet is appended: a circuit for, by examining the sequence number appended to the received data unit, detecting loss of a packet that should be extracted from the data unit; and a circuit for, when packet loss is detected, inserting as many null packets as lost packets between packets extracted from data units before and after the data unit, wherein the data unit is segmented into a plurality of cells that are asynchronously transferred.
Claim 10
Dependent Claim
47 words
An apparatus according to claim 7, wherein the circuit for detecting packet loss includes: a circuit for determining whether the data unit has been received correctly; and a circuit for examining the sequence number only when it is determined that the data unit has been received correctly.
Claim 11
Dependent Claim
38 words
An apparatus according to claim 8, wherein the circuit for determining whether the data unit has been received correctly includes a circuit for determining whether the cells carried in the received data unit have each been received correctly.
Claim 12
Dependent Claim
53 words
An apparatus according to claim 7, wherein the circuit for inserting null packets includes: a buffer for storing the packet extracted from the received data unit; and a circuit for selecting one of the packet stored in the buffer and a null packet, depending on whether packet loss has been detected or not.
Claim 13
Dependent Claim
34 words
An apparatus according to claim 7, wherein the data unit is a CPCS-PDU defined at the ATM Adaptation Layer Type 5, and the sequence number is stored in a CPCS-UU field in the CPCS-PDU.
Claim 14
Dependent Claim
15 words
An apparatus according to claim 11, wherein the packet is an MPEG-2 transport stream packet.
References Cited (Backward Citations)
US5442400A
Cited
US5566174A
Cited
US5579183A
Cited
US5596581A
Cited
US5657316A
Cited
US5740173A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-03-01 | 2002-08-31 | 2003-03-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-03-01 | 2006-08-31 | 2007-03-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-03-01 | 2010-08-31 | 2011-03-02 | $7700.00 | Window Closed / Lapsed |