Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L12/00—Data switching networks
  • H04L12/54—Store-and-forward switching systems 
  • H04L12/56—Packet switching systems
  • H04L12/5601—Transfer mode dependent, e.g. ATM
  • H04L12/5602—Bandwidth control in ATM Networks, e.g. leaky bucket
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04Q—SELECTING
  • H04Q11/00—Selecting arrangements for multiplex systems
  • H04Q11/04—Selecting arrangements for multiplex systems for time-division multiplexing
  • H04Q11/0428—Integrated services digital network, i.e. systems for transmission of different types of digitised signals, e.g. speech, data, telecentral, television signals
  • H04Q11/0478—Provisions for broadband connections
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L12/00—Data switching networks
  • H04L12/54—Store-and-forward switching systems 
  • H04L12/56—Packet switching systems
  • H04L12/5601—Transfer mode dependent, e.g. ATM
  • H04L2012/5629—Admission control
  • H04L2012/563—Signalling, e.g. protocols, reference model
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L12/00—Data switching networks
  • H04L12/54—Store-and-forward switching systems 
  • H04L12/56—Packet switching systems
  • H04L12/5601—Transfer mode dependent, e.g. ATM
  • H04L2012/5629—Admission control
  • H04L2012/5631—Resource management and allocation
  • H04L2012/5636—Monitoring or policing, e.g. compliance with allocated rate, corrective actions
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L12/00—Data switching networks
  • H04L12/54—Store-and-forward switching systems 
  • H04L12/56—Packet switching systems
  • H04L12/5601—Transfer mode dependent, e.g. ATM
  • H04L2012/5638—Services, e.g. multimedia, GOS, QOS
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L12/00—Data switching networks
  • H04L12/54—Store-and-forward switching systems 
  • H04L12/56—Packet switching systems
  • H04L12/5601—Transfer mode dependent, e.g. ATM
  • H04L2012/5638—Services, e.g. multimedia, GOS, QOS
  • H04L2012/5646—Cell characteristics, e.g. loss, delay, jitter, sequence integrity
  • H04L2012/5651—Priority, marking, classes
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L12/00—Data switching networks
  • H04L12/54—Store-and-forward switching systems 
  • H04L12/56—Packet switching systems
  • H04L12/5601—Transfer mode dependent, e.g. ATM
  • H04L2012/5638—Services, e.g. multimedia, GOS, QOS
  • H04L2012/5646—Cell characteristics, e.g. loss, delay, jitter, sequence integrity
  • H04L2012/5652—Cell construction, e.g. including header, packetisation, depacketisation, assembly, reassembly
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L12/00—Data switching networks
  • H04L12/54—Store-and-forward switching systems 
  • H04L12/56—Packet switching systems
  • H04L12/5601—Transfer mode dependent, e.g. ATM
  • H04L2012/5678—Traffic aspects, e.g. arbitration, load balancing, smoothing, buffer management
  • H04L2012/5681—Buffer or queue management

Definitions

• PSTN Public Switched Telephone Network
• PSPDN Packet Switched Public Data Network
• Congestion may occur at any time
• HDLC High Level Data Control
• the PSTN is inefficient in carrying data because the channel occupies bandwidth whether or not it carries information.
• the PSPDN is not able to carry a voice dialogue because of the delay-variation introduced by statistical-multiplexing and the integral HDLC protocol.
• ATM Asynchronous Transfer Mode
• the present invention is to
• ATM Asynchronous Transfer Mode
• the buffers being for Constant Bit-Rate (CBR) traffic, Sustainable Cell-Rate (SCR) traffic
• ABR Available Bit-Rate
• the SCR and ABR buffers being controlled by increasing the output rate of a buffer by a small increment when the contents of the buffer exceed an upper specified value and reducing the
• Figure 1 shows a block diagram illustrating an ATM Access Upstream Buffer for use in the present invention
• Figure 2 shows a block diagram illustrating Traffic Shaping and Congestion Avoidance as carried out in the present invention
• Figure 3 shows a block diagram illustrating the ATM Flow-Control Loop of the present invention.
• ATM traffic classes these are:-
• One of these traffic classes is associated with each virtual-channel at set-up time.
• the SCR and ABR traffic-classes together are defined as bursty; that is, the instantaneous bandwith occupied by a virtual-channel (VC) is continuously varying.
• the mean bandwidth of a bursty VC is substantially lower than the peak bandwidth.
• An ATM switch will provide a multiplexing function at its output ports including a memory buffer which allows the multiple sources to queue for access to the bearer, thus smoothing the traffic flow.
• the probabiUty of coincidence of peaks resulting in overflow of the finite memory of the buffer queue is relatively low.
• the quality-of-service provided in terms of cell-loss probability, is dependent upon the maximum permitted peak channel bandwidth (the lower the channel bandwidth the larger the
• Limiting the VC peak bandwidth is a function of the system control and VC policing
• switch memory-buffers need to be relatively small both to minimise cost
• Bursty traffic can, however, be "conditioned" in the access network
• the size of the bursty traffic buffer is maintained between limits by the mechanisms shown in Figure 2. If the queue size falls below the lower limit then the output rate from the buffer is incrementally reduced; similarly, if the size goes above the upper limit the output rate
• the cell-type field also provides for identifying a resource-management (RM) cell which is transmitted over the return path of the related Virtual-Channel and carries the congested- message.
• RM resource-management
• RM cells are returned at regular intervals (e.g. every N cells received on the channel) whether or not a persistence of congested-indications has been detected.
• An RM Cell received at the source may indicate one of three conditions of the upstream

Landscapes

• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Signal Processing (AREA)
• Data Exchanges In Wide-Area Networks (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (2)

Family

ID=10776789

Family Applications (1)

Country Status (6)

Cited By (3)

Families Citing this family (2)

Family Cites Families (3)

• 1995
  • 1995-06-28 GB GBGB9513138.9A patent/GB9513138D0/en active Pending
• 1996
  • 1996-06-21 AU AU62330/96A patent/AU6233096A/en not_active Abandoned
  • 1996-06-21 EP EP96920950A patent/EP0835574A2/en not_active Withdrawn
  • 1996-06-21 JP JP9504231A patent/JPH11508735A/ja active Pending
  • 1996-06-21 WO PCT/GB1996/001502 patent/WO1997001913A2/en not_active Application Discontinuation
  • 1996-06-21 GB GB9613064A patent/GB2305576A/en not_active Withdrawn
• 1997
  • 1997-12-29 NO NO976097A patent/NO976097L/no unknown

Non-Patent Citations (4)

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