Broadband switching network with automatic bandwidth allocation

Details Broadband switching network with automatic bandwidth allocation Broadband switching network with automatic bandwidth allocation

1996-03-22

1998-07-21

Olms, Douglas W.

Multiplex communications

Data flow congestion prevention or control

Control of data admission to the network

370395, 370468, H04Q 1104

Patent

active

057843589

DESCRIPTION:

BRIEF SUMMARY
BACKGROUND OF THE INVENTION

1. Field of the Invention
This invention relates to a broadband switching network for the switching of asynchronously transferred data cells, and to a method of switching asynchronously transmitted data cells.
2. Related Art
Broadband switching networks for switching asynchronously transferred cells are known, in which a predetermined level of bandwidth is allocated to a transmission channel connecting a first customer to a second customer. In some of these known systems, a communications channel is provided over a significant period of time, effectively of the leased-line type, and manual measures are implemented in order to set up such a connection or to modify a connection according to the particular terminations and the level of traffic being conveyed. Consequently, it is usual for customers to incur a fixed rate charge as part of the overall charge for the connection, resulting in payment being made irrespective as to whether the connection is being used or not.
Alternative systems have been proposed or are available. In particular, it is possible for connections to be established on a dial-up basis, requiring termination equipment to be provided with facilities for establishing connections by issuing signalling commands and responding to similar commands issued by the network.
The use of permanent circuits to support a private communications network is widespread. The demand for such circuits is expected to grow to include broadband rates above 2 Mbit/s, the circuits carrying traffic multiplexed from sources which are inherently bursty, possibly together with traffic which is transmitted at constant bit rates and is delay sensitive, such as voice transmission and constant bit-rate video.
Asynchronous transfer mode (ATM) cells all have a fixed information field of forty eight octets which can carry customer traffic or customer-originating control information (signalling). These two types of data transmission are distinguished by setting virtual path (VP) and vertical circuit (VC) values in the cell headers. Another field provided in the ATM header is known as cell loss priority, which enables low priority cells to be distinguished from high priority cells. In the event of congestion, the low priority cells may be discarded first.
For private circuits within an ATM based network, the desired route, the required bandwidth, and the quality of service (QOS) are set up using network management procedures. The private circuits are known as permanent virtual circuits (PVCs) because there is no actual physical circuit, only a VP/VC value or "label" which is associated with information stored in the switches to determine the route and preserve the bandwidth and QOS requirements.
A disadvantage of all known permanent circuits is that the bandwidth remains assigned to the circuit, even when the customer has nothing to transmit. This means that the customer may have to pay higher charges than would be obtained if the bandwidth was only made available when needed. The assumption being made here is that charging is related to reserved bandwidth, and this is not necessarily correct in terms of the way public network operators may choose to charge for virtual circuits. However, it is expected that charging based on reserved bandwidth will become a significant factor in the future.
A common practice is to set up a permanent virtual circuit so that it is only available during certain hours of the day, or during certain days of the week. A difficulty with this approach is that it does not allow the customer to change the pattern of usage quickly, and it may only crudely reflect the usage required by the customer.
A second proposal has been to provide the customer with a separate communications channel to the network management plane, thereby allowing a permanent virtual circuit to be reconfigured. A difficulty with this approach is that some time delay will be incurred before the customer can start to use the virtual circuit.
A third proposal is to introduce equipment at every switching poin

REFERENCES:
patent: 5271005 (1993-12-01), Takase et al.
patent: 5289462 (1994-02-01), Ahmadi et al.
patent: 5291481 (1994-03-01), Doshi et al.
patent: 5313454 (1994-05-01), Bustini et al.
patent: 5315586 (1994-05-01), Charvillat
patent: 5377327 (1994-12-01), Jain et al.
Crocetti et al, IEEE Infocom '91, vol. 3,7 Apr. 1991, Bal Harbour, pp. 1145-1150 "Bandwidth Advertising for MAN/ATM Connectionless Internetting".
Saito et al, Transactions of the Institute of Electronics, Information and Communications Engineers, vol. E74, No. 4, Apr. 1991, Tokyo, pp. 761-771, "Traffic Control Technologies in ATM Networks".
Tranchier et al, International Switching Symposium, vol. 2, Oct. 1992, Yokohama, pp. 7-11, "Fast Bandwidth Allocation in ATM Networks".
Chao et al, International Switching Symposium, vol. 1, 25 & 30 Oct. 1992, Yokohama, pp. 1229-1233, "A General Architecture for Link-Layer Congesion Control in ATM Networks".

Affiliated with

Also associated with

Rating

Broadband switching network with automatic bandwidth allocation does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Broadband switching network with automatic bandwidth allocation , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Broadband switching network with automatic bandwidth allocation will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1653995