Multiplex communications – Communication techniques for information carried in plural... – Adaptive
Reexamination Certificate
1999-04-16
2003-05-06
Chin, Wellington (Department: 2664)
Multiplex communications
Communication techniques for information carried in plural...
Adaptive
Reexamination Certificate
active
06560242
ABSTRACT:
TECHNICAL FIELD OF THE INVENTION
The invention relates generally to communication systems, and more particularly a method and apparatus for connection format conversion in communication systems.
BACKGROUND OF THE INVENTION
Communication between a calling party and a called party may be established over a communication network. Such a communication network may include a plurality of network switches that transport data in one of a variety of data transport protocols. Asynchronous transfer mode (ATM) technology is becoming the technology of choice for such broadband data communications. Within such ATM systems, a number of different service categories exist to facilitate the needs of different users.
Service categories supported by ATM can be grouped into real-time and non-real-time service categories. Real-time service categories include constant bit rate (CBR) and real-time variable bit rate (rt-VBR). Non-real-time service categories including non-real-time variable bit rate (nrt-VBR), available bit rate (ABR), and unspecified bit rate (UBR). Each of these different service categories includes a set of parameters that characterize the traffic contract that controls transmission of data within the data communications network. These parameters define the quality of service (QoS) for each given connection within the ATM network.
Nrt-VBR can be characterized as a bandwidth-on-demand (BOD) service category that tends to be used in non-real-time applications that are “bursty” in nature, where “bursty” indicates that the data is often transmitted in short, concentrated, bursts. These types of connections typically require a committed cell loss ratio (CLR), which is expected to remain constant during the existence of the connection. The UBR service category is typically associated with non-real-time applications that have no service guarantee required by the ATM network. UBR is typically associated with a BOD type of connection that uses the leftover bandwidth in the network once all other service categories have consumed their bandwidth requirements.
When connections are established for UBR and nrt-VBR service categories, the characteristics of the connection are often dependent on available resources within the network at that particular time. In many cases, the available resources in the network change during the existence of the connection. However, once a UBR or nrt-VBR connection is established, the parameters that describe the data carrying capacity of the connection cannot be altered unless the connection is terminated and reestablished. This can lead to inefficient use of network resources, as additional bandwidth carrying capability may be present but not utilized because of the lack of feedback in UBR and nrt-VBR connections.
Therefore, a need exists for a method and apparatus that allows for nrt-VBR and UBR connections to be provided with the means to adjust data transmission rates based on current network characteristics.
REFERENCES:
patent: 5452297 (1995-09-01), Hiller et al.
patent: 5689550 (1997-11-01), Garson et al.
patent: 5982783 (1999-11-01), Frey et al.
patent: 6094431 (2000-07-01), Yamato et al.
patent: 6243383 (2001-06-01), Li et al.
patent: 6262992 (2001-07-01), Nelson et al.
patent: 6301251 (2001-10-01), Kim et al.
patent: 6349097 (2002-02-01), Smith
patent: 6392994 (2002-05-01), Dubuc
U.S. patent application Publication No. US 2002/0145977, Delattre et al., Oct. 10, 2002., Method For The Control Of Flows Within An ATM Switch With Distributed Architecture., p. 1 [0009].
Behki Nutan
Hamedani Roxana
Alcatel Canada Inc.
Chin Wellington
Fox Jamal
LandOfFree
Method and apparatus for connection format conversion in a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for connection format conversion in a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for connection format conversion in a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3061668