JP2007520095A - Method and system for dynamic network channel correction - Google Patents

Abstract

  Embodiments of the present invention include methods and systems for setting and modifying network allocation parameters.

Description

(Cross-reference with related applications)
The present invention is invented by Daniel J. Park, Deepak Ayagari, J. M. Peponides and James E. Petranovish, and the title of the invention is "sub-channel reconfiguration in OFDM system". It claims the benefit of US Provisional Patent Application No. 60 / 518,224, filed on Nov. 7.

  In communication systems that use multiple subchannels to transmit data from one device to another, such as wireless, wired or power line network systems, the selection of the destination subchannel to achieve various goals And modulation in each subchannel can be adjusted. An Orthogonal Frequency Division Multiplexing (OFDM) system is an example of a system that performs multi-channel and modulation settings.

(Summary of the invention)
In communication systems that use multiple subchannels to transmit data from one device to another, such as a wireless, wired or power line network system, to maximize network efficiency, Selection and modulation on each subchannel can be set. After initial assignment and configuration of subchannels for connections, the system can continue to monitor network performance and make adjustments to the subchannel assignments or modulation on each subchannel. In some embodiments, the communication system may strive to maximize network utilization while meeting the QoS requirements for various connections within the network.

  In an embodiment of a network system having multiple subchannels, the performance of the channel between any two communication devices can be monitored. The selected subchannels of the destination and the modulation used on these subchannels can be configured based on the network performance experienced by the two devices.

  The above and other objects, features and advantages of the present invention will be more readily understood by considering the following detailed description of the present invention with reference to the accompanying drawings.

  In an embodiment of the present invention, decisions for sub-channel re-configuration can be concentrated in a device referred to as a central coordinator (CCo) in the network. This CCo may have a global view of network performance, including but not limited to network requests from all communication devices. In some embodiments, CCo can use this global view of network state to balance the competing needs of various active connections. In these embodiments, the CCo can reconfigure subchannels for connections between two or more devices. While this reconfiguration appears to be less optimal from a device standpoint, it can improve overall system performance.

  For example, multiple subchannels can be assigned to a connection, where each of the subchannels is narrow in bandwidth, but overall it can meet the QoS needs of the connection. Alternatively, a small number of high performance subchannels that meet the same QoS needs can be assigned to the connection. The CCo can also make these assignments, but this means that the high performance subchannel serves the second connection even if the second connection has a lower priority than the first connection. This is because it is the only subchannel. The device of the first connection regards this assignment as sub-optimal, but the assignment is optimal because the QoS requirements of the two connections are satisfied from the viewpoint of the system.

  In network systems with multiple subchannels whose channel performance varies over time, by adding or removing a set of subchannels assigned to the connection, or by changing the modulation type or modulation density of the subchannels You can modify the set of subchannels assigned to a connection. Since many connections compete in the network to access the subchannel, the CCo can consider many system parameters when changing the set of subchannels assigned to the connection.

The list of parameters considered by CCo includes, but is not limited to:
• Performance of each subchannel between each pair of devices (bandwidth and error rate)
Whether the current assignment of subchannels and these assignments are for connections with higher or lower priority than the connection under consideration. Additional network efficiency costs for subchannels that must be added-Additional network efficiency costs for subchannels that must be allocated as pilot signals based on the modulation of the subchannel under consideration

  The CCo can consider the demands on network resources from all connections and processes in deciding how to best reallocate resources for active connections to maximize overall network utilization.

  Embodiments of the present invention can be implemented in various network systems including, but not limited to, power line networks, wireless networks, wired networks, and others. Avalanche network protocol described in the avalanche specification: power line communication (PLC) AV, avalanche protocol specification; version 4.4.1, October 8, 2003 (the contents of which are incorporated herein by reference) A specific embodiment can be realized.

  With reference to FIG. 1, some embodiments of the present invention will be described. In these embodiments, CCo6 can trigger a connection modification or reconfiguration process to manage the allocation of network resources. For example, the CCo 6 can change or move the assignment to the connection to solve the channel quality problem or the problem caused by the resource request 8. CCo 6 can also periodically allocate bandwidth to connection 10. When periodic assignments are made, there may be no conflicting assignments, but later higher priority assignments may cause conflicts. In this case, the periodic assignment can be modified or reconfigured to prevent these conflicts.

  The reconfiguration process can also be triggered 12 by devices 2 and 4 that request bandwidth for connections that do not have a permanent allocation. In this case, the connection may be modified to increase or decrease the bandwidth allocated to the connection. This reconfiguration process may be triggered by devices 2 and 4 in response to new QoS needs 14 for connections as required by applications at devices 2 and 4. For example, current connections can start streaming multimedia content, but this requires a higher QoS priority than static content.

  In some embodiments, the CCo 6 can send a reconfiguration message 16 to the two devices 2 and 4 involved in the connection. This message can specify an assignment for the reconfigured physical channel. These two devices 2 and 4 can send a response message to the CCo to report the performance observed on the reconfigured connections 18 and 20. This connection is maintained 22 and user traffic can be performed with this new configuration of subchannels.

  With reference to FIG. 2, some embodiments of the present invention can be described. In these embodiments, a connection is established 24 between network devices. A need for connection correction is then detected 26. This detection can be performed by one of the devices utilizing the connection or by a third device operating as a central coordinator (CCo). In some embodiments, the CCo can reside on one of the devices using the connection. Detection may include passively waiting for a signal or message, or may include actively monitoring a device, network or other component for a change in condition. Once the needs are detected 26, the network connection may be modified 28 to meet the requirements or conditions imposed by the needs.

  Detection can include actively detecting a change in channel characteristics or a change in resource requirements. Detection can also include detection of an allocation request, which results in contention with the current allocation or degradation of the current allocation when allocated. Detection includes passively waiting for signals such as requests for higher bandwidth, requests for new connections, requests for higher priority QoS allocation, or messages or requests including but not limited to other messages. be able to.

  Some embodiments of the invention shown in FIG. 3 include a connection change request. In these embodiments, a network connection is established 30 by a central coordinator (CCo). This central coordinator may be part of a network device that shares the connection, or may be a separate entity that controls the network connection and their parameters. After the connection is established 30, a connection change request is received 32 by the CCo. This request may include a bandwidth change request, a QoS change request, a channel change request, a time slot change request, or a request for other changes in network allocation parameters. Once the request is received 32, the connection can be modified 34 in some way to improve the connection or be more tolerant to channel conditions.

  The embodiment of the invention shown in FIG. 4 includes detection of changes in network conditions. In these embodiments, a network connection is established 40 and a change in network conditions is detected 42. In these embodiments, this detection may include active detection of changes in network conditions. These conditions may include network conditions such as network traffic conditions, network channel interference, network medium stability, QoS priority of other connections, bandwidth required for other connections and other network conditions (limited to these). Active detection) that includes (not) the monitor. Once a change is detected 42, the connection can be modified 44 to improve overall network performance or to improve a particular connection or set of connections.

  The embodiment of the invention shown in FIG. 5 includes a separate central coordinator (CCo) that manages network connections. In these embodiments, the CCo establishes network connections and manages them. In one embodiment, CCo establishes 50 a connection between two or more network devices. The CCo detects 52 the need for network connection correction. As with the previously described embodiments, this detection can include active detection of changes in channel characteristics or changes in resource requirements. Detection can also include detection of an assignment request, which when assigned causes contention or degradation with the current assignment. Detection can also be a passive wait for a message or request, including, but not limited to, a request for a wider bandwidth, a request for a new connection, a request for a higher priority QoS allocation, or some other message. Can be included. If a modification need is detected 52, the network connection can be modified 54 to improve network conditions.

  With reference to FIG. 6, another embodiment of the present invention will be described. In these embodiments, active monitoring of network conditions is performed. A network connection is established 60 as in the other embodiments. Next, network conditions are actively monitored 62 to determine conditions that can affect connection performance. If a change in conditions occurs, the connection can be modified 64 to improve performance or reliability.

  Another embodiment of the invention shown in FIG. 7 includes a number of monitoring steps. In these embodiments, one or more network connections are monitored. One connection can be monitored 70 for subchannel performance. The connection can also be monitored 72 to maintain a connection priority, eg, QoS allocation track. With these network connection parameters monitored, an accurate picture of overall network efficiency can be maintained, specific connection assignments can be modified 74 to increase overall network efficiency or specific connection efficiency or performance.

  Next, still another embodiment of the present invention can be described with reference to FIG. In these embodiments, a network condition is detected 82 to establish 80 a network connection and determine whether the modification of the connection can improve the network or connection performance. If a condition is detected, a modified connection assignment can be created 84, but not immediately. This modified assignment is sent 85 to the device being serviced by the connection, and one or more of these devices test 86 the performance of the modified assignment. The test device can then respond 87 to a network management authority, eg CCo, with a message indicating the modified allocation performance or its tolerance. If the performance of the modified allocation is acceptable 88, use the modified allocation 89. If performance is unacceptable, create a new revised assignment and test until an acceptable assignment is found.

  Some device embodiments of the present invention shown in FIG. 9 may include a network management authority 90, eg, CCo, which includes a connection performance monitor 92, a connection priority monitor 94, and network connection parameters. Includes an assigner 96 for assigning and modifying.

  Some device embodiments of the present invention shown in FIG. 10 may include a network management authority 100, eg, CCo, which establishes a network condition and a connection establisher 102 for establishing a connection. It includes a network condition detector 104 for detecting and a connection modifier 106 for correcting the network connection.

  With reference to FIG. 11, some embodiments of the present invention can be described. These embodiments may include an exemplary network system that includes a central coordinator (CCo) 110 that manages network connections. These embodiments may also include network devices, such as a first network device 114 and a second network device 116. These network devices include computing devices such as desktop or laptop computers, personal digital assistants (PDAs), printers, copiers and other computing devices capable of communicating through network media. These embodiments further comprise a network medium 112 through which communication can be made. In this embodiment, CCo 110 is a computing device that is physically separate from first device 114 and second device 116. In some embodiments, the CCo may be part of a connected network device.

  In this embodiment, CCo 110 can create and manage network connections. If the first device 114 requests a connection with the second device 116, the CCo 110 can set up a connection 118 between the two devices. The CCo 110 may further detect network changes and take into account these network changes or modify this or other network connections to accommodate them.

  The terms and expressions used so far in the specification are used as terms for describing the invention, and are not used for limiting the invention. It is recognized that the use of such terms and expressions is not intended to exclude the features shown and described in the specification or equivalents thereof, and the scope of the present invention is limited only by the claims.

FIG. 6 shows an overview of several connection modification embodiments of the present invention. FIG. 6 is a chart illustrating an example that includes detecting connection modification needs. FIG. It is a chart which shows the Example containing a connection change request. 6 is a chart showing an embodiment including detection of changes in network conditions. It is a chart which shows the Example including the detection of the need of the connection correction by CCo. 6 is a chart showing an embodiment including monitoring of network conditions. 6 is a chart illustrating an embodiment including a subchannel performance monitor and an allocation priority monitor. FIG. 6 is a chart illustrating an example including a modified assignment test. FIG. FIG. 5 illustrates an example of a device including a subchannel performance monitor and an allocation priority monitor. FIG. 6 illustrates an example of a device that includes needs detection. 1 illustrates an example of an exemplary system.

Claims (33)

a) establishing a network connection with network allocation parameters;
b) detecting the need for modification of the network allocation parameters for the connection;
c) modifying the connection allocation parameters for the network connection to meet the needs;
A method for modifying network assignment parameters for a network connection, comprising:   The method of claim 1, wherein the detecting comprises receiving a bandwidth change request.   The method of claim 1, wherein the detecting comprises receiving a QoS change request.   The method of claim 1, wherein the detecting comprises detecting a change in network channel conditions.   The method of claim 1, wherein the detecting comprises detecting a fixed periodic assignment that interferes with the connection.   The method of claim 1, wherein the detecting comprises receiving potential interference of a connection request having a higher QoS priority.   The method of claim 1, wherein the detecting comprises receiving a new network connection request that is not satisfied for the network connection without modifying the network allocation parameters.   The method of claim 1, wherein the detecting comprises detecting inefficiency of the entire network. a) establishing a network connection with a central coordinator (CCo), wherein the connection is between a first network device and a second network device, the connection including network allocation parameters;
b) detecting by the CCo the need to modify the network allocation parameters for the connection;
c) modifying the connection allocation parameters for the network connection by the CCo to meet the needs;
A method for modifying network assignment parameters for a network connection, comprising:   The method of claim 9, wherein the detecting comprises receiving a bandwidth change request.   The method of claim 9, wherein the detecting comprises receiving a QoS change request.   The method of claim 9, wherein the detecting comprises detecting a change in network channel conditions.   The method of claim 9, wherein the detecting comprises detecting a fixed periodic assignment that interferes with the connection.   The method of claim 9, wherein the detecting comprises receiving potential interference of a connection request having a higher QoS priority.   The method of claim 9, wherein the detecting comprises receiving a new network connection request for the network connection that is not satisfied without modifying the network allocation parameters.   The method of claim 9, wherein the detecting comprises detecting inefficiency of the entire network. a) establishing a network connection including network allocation parameters;
b) monitoring network conditions;
c) modifying the network allocation parameters for the network connection when the network conditions meet criteria;
A method for modifying network assignment parameters for a network connection, comprising:   The method of claim 17, wherein the network condition comprises a network channel condition.   The method of claim 17, wherein the network conditions include assignments for other connections.   The method of claim 17, wherein the network conditions include QoS priorities for other connections.   The method of claim 17, wherein the network conditions include overall network efficiency.   The method of claim 17, wherein the network condition comprises a change in error rate for a subchannel.   The method of claim 17, wherein the network condition includes an amount of connections.   The method of claim 17, wherein the network condition includes a relative priority of connections. a) monitoring the performance of the subchannels assigned to the device;
b) monitoring the priority of the subchannel assignments;
c) modifying at least one of the subchannel assignments to improve the efficiency of the entire network;
A method for allocating network resources characterized by comprising:   26. The method of claim 25, further comprising monitoring an additional network efficiency cost of a subchannel that must be assigned as a guard band based on the subchannel modulation.   26. The method of claim 25, further comprising monitoring additional network efficiency costs of subchannels that must be assigned as pilot signals based on the subchannel modulation.   26. The method of claim 25, wherein the monitoring and modifying steps are performed by a central coordinator (CCo). a) a performance monitor for monitoring the performance of the subchannels assigned to the device;
b) a priority monitor for monitoring the priority of assignment of the subchannels;
c) an allocator for assigning and modifying at least one of the sub-channel assignments so as to improve the overall network efficiency;
An apparatus for modifying a network allocation parameter, comprising:   30. The apparatus of claim 29, further comprising a network efficiency monitor for monitoring additional network efficiency costs of subchannels that must be assigned as guard bands based on subchannel modulation.   30. The apparatus of claim 29, further comprising a network efficiency monitor for monitoring additional network efficiency costs of subchannels that must be assigned as pilot signals based on the subchannel modulation. a) a connection establisher for establishing a network connection including network assignment parameters;
b) a detector for detecting the need for changing network assignment parameters;
c) a connection modifier for modifying network allocation parameters when needs are detected;
An apparatus for modifying a network allocation parameter, comprising: a) a central coordinator (CCo);
b) a first network device;
c) a second network device;
d) a communication medium connecting the CCo, the first network device, and the second network device;
e) the CCo establishes a connection between the first network device and the second network device, the connection including network allocation parameters;
f) the CCo detects the condition of the medium;
g) the CCo modifies the network allocation parameters according to the conditions;
A system for managing network connections.

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