TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to network communications, and more particularly, to a versatile system for dynamic bandwidth adjustment and trading among client nodes sharing network link resources.

BACKGROUND OF THE INVENTION

Automatically Switched Optical Network (ASON)/Generalized Multi-protocol Label Switching (GMPLS) protocols are commonly used to set up point to point paths, or to dynamically adjust (increase/decrease) bandwidth of point to point paths in a Connection-Oriented Packet Service (COPS) environment. However, in a Connectionless Packet Service (CLPS) application, it is not required that a connection be established between a sender and receiver, and there is lack of mechanism in conventional systems that allows for dynamic bandwidth adjustment among client nodes.

In a conventional aggregation network (100) with a shared link, illustrated in FIG. 1, each client is connected to network (100) via an access port, such as port (131), (132), (133), (134), (135) and (136). All access port traffic is aggregated to a network node (104) via network nodes (112), (114), (116), (118) and (120), and then routed to core node/switch (102) via network node (104). In this topology, all access ports (131)-(136) share bandwidth on trunk (106) to core node/switch (102).

A conventional practice for network bandwidth control involves limiting ingress rate at each access port to be under certain Committed Information Rate (CIR), such as CIR1-CIR6 associated with each access port illustrated in FIG. 1. However, there are instances where some ports may need higher bandwidth only for some period of time. Under conventional practices, those ports may have to acquire the maximum bandwidth they may possibly utilize, even though they may actually only need high bandwidth within a small time window. In these instances, conventional practices lack flexibility and lower efficiency in bandwidth utilization.

Therefore, there is a need to provide a dynamic bandwidth sharing capability among clients that share network link resources, and to improve bandwidth sharing flexibility and efficiency.

SUMMARY OF THE INVENTION

The present invention discloses a system, comprising various constructs and methods, for dynamic bandwidth adjustment or trading among clients ports that share network link resources in a communication network. Upon receipt of a bandwidth adjustment request from a client, the present system determines request acceptability using network link capacity. If network link capacity meets the bandwidth adjustment request, the present system adjusts Committed Information Rate (CIR) of the requesting client. If network link capacity does not meet the bandwidth adjustment request, the present system attempts to acquire unused bandwidth from any other client ports to meet the bandwidth request of the requesting client, and adjusts CIR of the requesting client and any other client ports offering bandwidth for trade.

The present invention provides dynamic bandwidth sharing capabilities among clients that share network link resources, and improves bandwidth sharing flexibility and efficiency.

The present invention may provide dynamic bandwidth sharing capabilities through exchange of signaling messages in a control plane, or through a bandwidth manager in a management plane. The bandwidth trading of the present invention may be performed in either centralized or distributed fashion.

The following description and drawings set forth in detail a number of illustrative embodiments of the invention. These embodiments are indicative of but a few of the various ways in which the present invention may be utilized.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts:

FIG. 1 depicts an aggregation network with a shard link;

FIG. 2 depicts a flow chart illustrating operation of dynamic bandwidth adjustment and trading through exchange of signaling messages according to the present invention; and

FIG. 3 depicts signaling sequences for dynamic bandwidth trading through exchange of signaling messages according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The following discussion is presented to enable a person skilled in the art to make and use the invention. The general principles described herein may be applied to embodiments and applications other than those detailed below without departing from the spirit and scope of the present invention as defined herein. The present invention is not intended to be limited solely to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

The present invention discloses a system for dynamic bandwidth adjustment or trading among client nodes sharing network link resources. The present invention provides different mechanisms to achieve dynamic bandwidth adjustment or trading. For example, the dynamic bandwidth adjustment or trading may be performed in a control plane through exchanging signaling messages, or it may be performed in a management plane through bandwidth management.

Referring now to FIG. 2, a flowchart (200) illustrates operation of dynamic bandwidth adjustment and trading, among a group of client nodes sharing network link resources, through exchange of signaling messages in accordance with the present invention.

Bandwidth adjustment may begin from step (222), when a client (221) requests bandwidth increase from a network node (211). Network node (211) may be any node in a network that has knowledge of clients sharing the network link resources. Upon receipt of bandwidth increase request from client (221) in step (212), network node (211) determines, in step (213), whether such request may be accepted or not, using network link capacity information. If network link capacity is greater than, or equal to, total updated aggregate CIR bandwidth, then the request is accepted in step (214), and network node (211) may proceed in step (215) by notifying the port of client (221) with an updated CIR level. The total updated aggregate CIR bandwidth is the total amount of CIR of all client ports that share the network link capacity, with the requesting client port's CIR adjusted as requested. The transaction may be completed when the port of client (221) confirms with the update.

If network link capacity is less than total updated aggregate CIR bandwidth, network node (211) may send a multicast message in step (216) to each of the peers (i.e., all the other ports that share network link capacity with client (221)), inquiring if any of the peers may trade unused bandwidth in response to the request from client (221) for additional bandwidth. Each port may send a reply message back to network node (211) with an amount of bandwidth offered to trade. Upon receipt of reply messages from all participating peers, network node (211) determines whether the bandwidth increase request may be honored in step (217). If the bandwidth increase request is honored, in step (218), network node (211) informs each participating peer about the bandwidth increase results. Network node (211) also sends a notification message with adjusted CIRs to all trading peers that offer traded bandwidth in step (218). Once the reservation is confirmed, both requesting client (221) and trading peers update their CIRs. If the total amount of bandwidth offer to trade doesn't meet the bandwidth increase request, network node (211) informs the result to requesting client (221) in step (219).

Reference is now made to FIG. 3, which depicts a signaling sequence diagram (300) for an embodiment where bandwidth adjustment and trading are necessary due to limited shared link capacity. A requester (302) sends a bandwidth request message to a network node (304) in step (331), requesting bandwidth increase. Network node (304) multicasts the bandwidth request to peer1 (312), peer2 (314), peer3 (316), and peerN (318), by sending a bandwidth request multicast message in step (333), inquiring whether any peer may trade unused bandwidth to requester (302). Each of the peers (i.e., peer (312), (314), (316) and (318)) responds to the inquiry of network node (304) with an amount of bandwidth each peer may giveâ€”by sending a reply message to network node (304) in steps (335a), (335b), (335c) and (335d), respectively. Upon receiving reply messages sent in step (335), if network node (304) determines that the bandwidth increase request from requester (302) may be met by the total amount of bandwidth offered by peers (312), (314), (316) and (318), then network node (304) sends a bandwidth confirmation message in step (341) to requester (302), informing requester (302) that the bandwidth request is honored. Network node (304) also sends bandwidth adjustment confirmation messages to each peer for CIR adjustment in step (343a), (343b), (343c) and (343d), respectively. Requester (302) and peers (312), (314), (316) and (318) respond network node (304) by sending confirmation acknowledgement messages to network node (304) in step (347a), (347b), (347c) and (347d), completing bandwidth adjustment.

With the exchange of signaling messages described above, a client's request for bandwidth adjustment is met, and bandwidth adjustment is dynamically achieved. This may be performed via a control plane through exchange of signaling messages.

Other embodiments achieve dynamic bandwidth adjustment via a management plane through a bandwidth manager. In such instances, instead of a network node, with which client ports exchange messages, a bandwidth manager may assume the role of the network node to manage dynamic bandwidth adjustment. A bandwidth manager may identify a bandwidth need from a client, determine whether the need may be met, and adjust and/or trade bandwidth among peers of the client. An interface between client ports and the bandwidth manager may be a network management interface like Simple Network Management Protocol (SNMP).

The dynamic bandwidth adjustment and trading illustrated above is centralized. That is, a network node sends a bandwidth request massage to each of participating clients, and collects bandwidth information from the clients. Alternative embodiments adjust bandwidth dynamically in a distributed fashion. These alternative embodiments allow each client to come up with its own bandwidth profile information based on its historical link traffic utilization. A bandwidth profile may be a list of bandwidth utilization of a historical link in each period of time, and associated â€œresidualâ€ bandwidth a client is willing to â€œgive awayâ€ to peers upon request. This bandwidth profile may be created in a distributed fashion by each client node.

Once this information is made available to a network node, the network node may not have to send a bandwidth request multi-cast message to each client node as it already has the information. Therefore, upon a bandwidth request from a client, the network node may determine new CIRs for participating clients using the bandwidth profile, and send bandwidth adjustment messages to all clients.

The present invention may be applied in, but not limited to, Connectionless Packet Service (CLPS) applications, and multi-point to multi-point traffic type. The dynamic bandwidth trading may be included in a network service provider as a service type.

The previous description of the disclosed embodiments is provided to enable those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art and generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.