JP4031395B2 - Network bandwidth control method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bandwidth control technique in a network management system for a network composed of various communication methods and bandwidth control mechanisms.
[0002]
[Prior art]
The network is composed of network elements having various communication methods such as ATM (Asynchronous Transfer Mode), PON (Passive Optical Network), Ethernet (registered trademark), and IP (Internet Protocol). A network service is provided by combining these network elements.
[0003]
These network elements are provided with a bandwidth control mechanism corresponding to each communication method for the purpose of guaranteeing network QoS (Quality of Service). Hereinafter, the bandwidth control mechanism in each communication method will be described.
[0004]
ATM has a maximum bandwidth control mechanism that controls PCR (Peak Cell Rate) by a bandwidth control algorithm represented by a leaky bucket, and a minimum bandwidth control mechanism that controls MCR (Minimum Cell Rate). In addition, in ATM, in order to support various types of traffic, service categories of CBR (Constant Bit Rate), UBR (Unspecified Bit Rate), VBR (Variable Bit Rate), and GFR (Guaranteed Bit Rate) are defined. . Corresponding QoS requirements are defined for each service category. Specifically, CBR supports low-delay traffic and guarantees the peak rate of PCR. UBR supports best effort traffic with no delay guarantee, and sets a peak rate PCR as a bandwidth control parameter. In VBR, SCR (Sustainable Cell Rate) that is an average rate is guaranteed and PCR that is a peak rate is controlled to enable support of real-time traffic with low delay. In the GFR, the MCR that is the lowest rate is guaranteed and the PCR that is the peak rate is controlled to support traffic with less severe delay requirements.
[0005]
The PON has a minimum bandwidth control mechanism and a maximum bandwidth control mechanism by a DBA (Dynamic Bandwidth Allocation) algorithm. In B-PON (Broadband-PON), three types of bandwidth parameters, Fixed Bandwidth, Assured Bandwidth, and Maximum Bandwidth can be set by DBA. Fixed Bandwidth represents a band that is fixedly allocated, and is used to guarantee the band for low-latency traffic. The Assured Bandwidth is used to guarantee a minimum bandwidth of traffic that is not strict to delay. Maximum Bandwidth is used to set the maximum bandwidth. In GE-PON (Gigabit Ethernet-PON), the maximum bandwidth and the minimum bandwidth can be controlled by the DBA, and a service class corresponding to the delay requirements of the low delay service class and the normal delay service class can be set.
[0006]
In Ethernet and IP, the maximum bandwidth control mechanism by rate-limiting using bandwidth control algorithms typified by token bucket algorithms, and the minimum bandwidth control by scheduling algorithms typified by weighted fair queuing (WFQ) and WRR (weighted round robin). It has a mechanism. A priority queue for performing priority control based on CoS (Class of Service) is provided.
[0007]
A conventional network management system is individually constructed for each network composed of network elements of each communication method, and performs management and control for each network independently. The network management system has a network bandwidth control function, and supports the operation of network resources in each network by managing and controlling the bandwidth control function of each network element. Usually, in a network management system, network bandwidth control is executed on a logical path basis.
[0008]
In ATM, network bandwidth control is executed for each VP (Virtual Path) line or VC (Virtual Channel) line, and the VP connection in the network element through which the VP line and the VC line pass, and the termination point of the VC connection are control of the network bandwidth control. It becomes a target. The end point is described by a VP identifier and a VC identifier.
[0009]
The network bandwidth control in ATM will be described using the network shown in FIG. 18 as an example. The network shown in FIG. 18 includes network elements 301 to 303 representing VP switches or VC switches and physical links 311 and 312 connecting them. The VP lines or VC lines 321 and 322 are composed of VP connections or VC connections 351 to 362 terminated at termination points 331 to 344 in the network element. Network bandwidth control for a VP line or VC line is realized by the network management system setting a traffic descriptor (bandwidth control parameter) including the ATM service category, maximum bandwidth value, and minimum bandwidth value for each connection termination point. . For example, in the network bandwidth control for the line 321, traffic descriptors are set at the termination points 331 to 334.
[0010]
In PON, which is an access network communication method, network bandwidth control is executed for each access line. In B-PON, an ONU (Optical Network Unit), which is a network element installed as a subscriber side device, is a control unit. In GE-PON, a logical port provided in the ONU is a control unit.
[0011]
The network bandwidth control in the PON will be described using the network shown in FIG. 19 as an example. The network shown in FIG. 19 includes an OLT (Opical Line Terminal) 401 that is a station side device, ONUs 411 to 413 that are subscriber side devices, a splitter 421 that splits light, and physical links 431 to 434 that connect them. An access line exists in units of ONUs or logical units of ONUs. Network bandwidth control for the access line is realized by the network management system setting bandwidth control parameters for the OLT. In B-PON, DBA parameters including Fixed Bandwidth, Assured Bandwidth, and Maximum Bandwidth are set for each ONU. The GE-PON is realized by setting the DBA parameters including the maximum bandwidth value and the minimum bandwidth value and the service class for each logical boat of the ONU.
[0012]
In an Ethernet or IP network, network bandwidth control sets a combination of a physical port, layer 2 identification information, and layer 3 identification information as a filter condition in a network element (layer 2 switch, layer 3 switch, router, etc.) This is realized by specifying a bandwidth control parameter in the unit in which traffic is identified by the filter condition. Layer 2 network identification information uses VLAN-ID (Virtual Local Area Network-Identifier), IEEE 802.1p priority value, etc., and layer 3 network identification information includes a source IP address, a destination IP address, and a source A port number, a destination port number, a protocol type, a DSCP (Diffserv Code Point) value, a ToS (Type of Service) value, and the like are used.
[0013]
The bandwidth control in the Ethernet or IP network will be described by taking the network shown in FIG. 20 as an example. The network shown in FIG. 20 includes network elements 501 to 503 representing layer 2 switches, layer 3 switches, routers, and the like, and physical links 511 to 512 connecting them. Network bandwidth control for logically identified traffic units is realized by setting network elements 501 to 503 with filter conditions for identifying traffic, a bandwidth control mechanism and bandwidth control parameters corresponding to the filter conditions for the network management system to identify traffic. The bandwidth control parameter is the traffic flow value and burst size corresponding to the maximum bandwidth value when using the maximum bandwidth control mechanism based on Rate-Limiting, and corresponds to the minimum bandwidth when using the minimum bandwidth control mechanism based on WFQ or WRR. Set the queue output weight value or the number of withdrawal rights.
[0014]
The above-described bandwidth control mechanisms of the respective communication methods are very similar in function although the corresponding bandwidth control algorithms are different. Therefore, an individually constructed network management system has a similar network bandwidth control function.
[0015]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-84349
[Patent Document 2]
JP 2002-305538 A
[Patent Document 3]
JP 2000-253053 A
[Non-Patent Document 1]
"Development of ATM Network Integrated Management System (ANIMA)", NTT R & D May 1999 (Vol.48 No.5)
[Non-Patent Document 2]
“Examination of Access NW-OSS in Quality Control”, TM2001-97, pp. 61-66, Mar. 2002
[0016]
[Problems to be solved by the invention]
As described above, the conventional network management system is individually constructed for each communication method without performing unified network bandwidth control. Therefore, when a communication method is added or when a new network management system is constructed. There was a problem of increasing the cost of system construction.
[0017]
The object of the present invention is to realize network bandwidth control in a network management system that manages networks consisting of various communication methods without depending on the communication method of the managed network and without being aware of the difference in the communication method. It is an object of the present invention to provide a common network bandwidth control apparatus and method that can be used.
[0018]
[Means for Solving the Problems]
In order to achieve the above object, in the present application, the element management layer uses a directory to store and hold termination point information and element control information that abstracts the bandwidth control mechanism of the network element. A communication method for a managed network by storing and holding guaranteed bandwidth control information, peak bandwidth control information, and service quality class information that abstract the guarantee mechanism, and controlling the network using these abstracted control information. It is characterized in that the network bandwidth control is executed without depending on.
[0022]
More specifically, in claim 1, In response to a control request related to the guaranteed bandwidth of a line (trail) from an administrator or a host device In contrast, the network bandwidth controller In a network bandwidth control method for controlling a network element in a managed network, A line (trail) in a managed network consists of one or more connections separated by network elements, The network bandwidth controller is As management information in the element management layer, means for storing element control information abstracting the bandwidth control mechanism of each network element in units of connection termination points, and as management information in the network management layer, determined based on the element control information Means for storing guaranteed bandwidth control information, which is an abstraction of a guaranteed bandwidth guarantee mechanism, in connection end point units and trail units, and connecting peak bandwidth control information determined based on the element control information and the guaranteed bandwidth control information Means for storing each terminal point and trail unit, means for storing service quality class information in trail units in combination with the guaranteed bandwidth control information, and usable bandwidth for each service quality class in the link accommodating the connection Remember the value And means for storing logical termination point names as termination point information of the connections constituting the trail as management information in the network management layer, and network elements, physical ports, logical ports, etc. as management information in the element management layer Means for storing end point information constituted by identification information in a hierarchical structure of a directory, and using a logical name as a relative identification name representing an entry of each layer constituting the directory, and the end point as an attribute of an entry of each layer Means for storing network identification information of the hierarchy constituting the information, and means for converting from the logical termination point name to the directory identification name holding the termination point information, Determining whether or not the guaranteed bandwidth control related to the control request is possible with reference to the guaranteed bandwidth control information stored in the storage means for the trail specified in the control request; and the guaranteed bandwidth control is possible. In some cases, with reference to the guaranteed bandwidth control information stored in units of termination points of the connection constituting the trail, the termination point to be controlled by the control request is determined from the guaranteed bandwidth control information, Acquiring the logical termination point name of the termination point and the element control information from the storage means, creating an element control request message using the determined logical termination point name and element control information, and the conversion means The logical termination point name included in the element control request message is converted into a directory identification name, and a network representing the control target is converted. Obtaining the network identification information from the storage means, determining the bandwidth control mechanism from the element control information, and determining an element control message to be requested to each network element from the network identification information and the bandwidth control mechanism. And a step of controlling a network element using the element control message.
[0023]
In claim 2, For control requests related to the peak bandwidth of the line (trail) from the administrator or the host device Network bandwidth control device In a network bandwidth control method for controlling a network element in a managed network, A line (trail) in a managed network consists of one or more connections separated by network elements, The network bandwidth controller is As management information in the element management layer, means for storing element control information abstracting the bandwidth control mechanism of each network element in units of connection termination points, and as management information in the network management layer, determined based on the element control information Means for storing guaranteed bandwidth control information, which is an abstraction of a guaranteed bandwidth guarantee mechanism, in connection end point units and trail units, and connecting peak bandwidth control information determined based on the element control information and the guaranteed bandwidth control information Means for storing each terminal point and trail unit, means for storing service quality class information in trail units in combination with the guaranteed bandwidth control information, and usable bandwidth for each service quality class in the link accommodating the connection Remember the value And means for storing logical termination point names as termination point information of the connections constituting the trail as management information in the network management layer, and network elements, physical ports, logical ports, etc. as management information in the element management layer Means for storing end point information constituted by identification information in a hierarchical structure of a directory, and using a logical name as a relative identification name representing an entry of each layer constituting the directory, and the end point as an attribute of an entry of each layer Means for storing network identification information of the hierarchy constituting the information, and means for converting from the logical termination point name to the directory identification name holding the termination point information, For the trail specified in the control request, referring to the peak bandwidth control information stored in the storage means to determine whether the peak bandwidth control related to the control request is possible; and the peak bandwidth control is possible. In some cases, with reference to the peak bandwidth control information stored in the termination point unit of the connection constituting the trail, the termination point to be controlled by the control request is determined from the peak bandwidth control information, and Acquiring the logical termination point name of the termination point and the element control information from the storage means, creating an element control request message using the determined logical termination point name and element control information, and the conversion means The logical termination point name included in the element control request message is converted into a directory identification name, and the control target is displayed. Obtaining network identification information from storage means; determining the bandwidth control mechanism from the element control information; and determining an element control message to be requested to each network element from the network identification information and the bandwidth control mechanism. And a step of controlling a network element using the element control message.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
A network bandwidth control system according to an embodiment of the present invention will be described with reference to the drawings.
[0025]
First, terms used in the present invention will be described with reference to FIG. In the present invention, as shown in FIG. 1, a communication device such as a transmission device, a router, or a switch is called a network element, and a physical medium that connects the network elements is called a link. Further, a logical connection between network elements is called a connection, and a line composed of a series of connections is called a trail. In addition, in FIG. 1, aTP and zTP are termination points (Termination Point).
[0026]
FIG. 2 is a system configuration diagram illustrating the entire network bandwidth control system according to the present embodiment. As shown in FIG. 2, this system has a form in which an access network 20 that accommodates user terminals 10 and a core network 40 that accommodates a server 30 that provides services are connected. The server 30 and the core network 40 are connected via an edge router 41, and the core network 40 and the access network 20 are connected via an edge router 42. Although omitted in FIG. 2, the access network 20 and the core network 40 are composed of various network elements and physical links.
[0027]
Each network element in the access network 20 and the core network 40 is subjected to various control management such as bandwidth control by a communication control device called an operation support system (OSS). The OSS includes an access network OSS 50 that manages and controls the access network 20, a core network OSS 60 that manages and controls the core network 40, and a service OSS 70 that manages and controls the OSSs 50 and 60.
[0028]
In the access network 20, various communication systems such as ATM, PON, Ethernet, and IP are mixed. The present invention provides unified network bandwidth control in a network environment where such communication methods coexist. In this embodiment, a case where the present invention is applied to an access network OSS 50 that performs bandwidth control of the access network 20 will be described as an example.
[0029]
The access network OSS 50 performs bandwidth control by controlling network elements in the access network 20 in accordance with instructions from the service OSS 70 that is an administrator or a host device, and is used by the bandwidth control unit and the bandwidth control unit. A database (both not shown) for storing various information. Various information stored in the database and the operation of the bandwidth controller will be described in detail below.
[0030]
First, element control information will be described with reference to FIG. The element control information is defined by abstracting the bandwidth control mechanism included in the network element. That is, as shown in FIG.
Type A: Type that can control only the lowest bandwidth
Type B: Only the maximum bandwidth can be controlled
Type C: Type that can control both maximum bandwidth and minimum bandwidth
Can be classified into three element control types.
[0031]
The element control information is composed of an element control type and an element control parameter. The element control parameter is configured by a band value (maximum band, minimum band) and a service quality class. FIG. 4 shows the correspondence between the bandwidth control mechanism provided in the network element and the element control information obtained by abstracting the bandwidth control mechanism. Type A has minimum bandwidth and service quality class as element control parameters, Type B has maximum bandwidth and service quality class as element control parameters, and Type C has maximum bandwidth, minimum bandwidth, and service quality class as element control parameters. . Quality of service classes are defined on demand for delays. For example, as shown in FIG. 5, two classes, a low delay class and a normal delay class, can be defined. If the delay request is more detailed, it can be handled by defining a subclass of the low delay class.
[0032]
As shown in FIG. 4, the element control parameters are associated with the parameters of the bandwidth control mechanism provided in the network element of each communication method according to the element control type. A specific example will be described below with reference to FIG.
[0033]
For example, in the case of a layer 2 switch equipped with WRR or WFQ, only the lowest band can be controlled, so the element control type is type A. The minimum bandwidth value, which is an element control parameter, is converted into a WRR or WFQ queue output weight value (number of withdrawal rights). Considering the case where the physical speed of the output interface of the layer 2 switch is 100 Mbps and the total number of withdrawal rights is 100, the allocation of the number of rights corresponds to the minimum bandwidth of 1 Mbps. Therefore, when the minimum bandwidth of 6 Mbps is set, the number of 6 rights (weight value of 6/100) is assigned. When the minimum bandwidth of 6.5 Mbps is set, correction such as rounding up is necessary based on the bandwidth setting granularity (1 Mbps in the above example). As for the service quality class, when WRR or WFQ control is performed at the output interface, there is usually no mechanism for further priority control for the traffic to be controlled. Can be supported. If there is a scheduling mechanism that realizes a low delay for traffic subject to WRR or WFQ control, it can be handled by mapping it to a low delay class.
[0034]
Further, for example, in the case of a layer 2 switch equipped with rate-limiting, only the maximum bandwidth can be controlled, so the element control type is type B. The maximum bandwidth value, which is an element control parameter, is converted into a traffic flow value (commited rate), which is a rate-limiting setting parameter. The burst size for controlling the burst of traffic, which is another setting parameter of Rate-limiting, can be dealt with by setting a burst value corresponding to the maximum bandwidth value. Further, the service quality class is associated with a priority queue that supports CoS. In the case of the low delay class, association is performed with the highest priority queue having the highest priority in the priority control. When subclasses of the low delay class exist, the priority queues are associated in order according to their priorities. In the case of the normal delay class, it is associated with the priority queue of the next priority used in the low delay class.
[0035]
For example, in a PON equipped with a DBA, both the maximum bandwidth and the minimum bandwidth can be controlled, so the element control type is type C. In B-PON, the maximum bandwidth value that is an element control parameter is converted to Maximum Bandwidth that is a bandwidth parameter of DBA, and the minimum bandwidth value is converted to Fixed Bandwidth and Assured Bandwidth according to the service quality class. When the quality of service class is the low delay class, the minimum bandwidth value is converted to Fixed Bandwidth, and when the quality of service class is the normal delay class, the minimum bandwidth value is converted to Assured Bandwidth. In GE-PON, the maximum bandwidth value and the minimum bandwidth value as element control parameters are converted into the maximum bandwidth value and the minimum bandwidth value as bandwidth parameters of DBA. Regarding the service quality class, the low delay class is associated with the low delay service class defined by GE-PON, and the normal delay class is associated with the normal delay service class defined by GE-PON.
[0036]
FIG. 6 is a correspondence table between network element types and element control types included in the network elements. The correspondence table holds the relationship between the band control mechanism corresponding to each element control type and the element control message template for controlling the band control mechanism. The element control message template is a template for creating a message for controlling a network element, and is described according to the management protocol, management information, and bandwidth control mechanism supported by the network element. For example, in the case of a layer 2 switch that supports CLI (Command Line Interface) / telnet as a management protocol and rate-limiting as a bandwidth control mechanism, a command statement related to rate-limiting control and a traffic flow value (committed) that is a parameter thereof. rate) and a text message template including a part for entering a burst size is prepared. In addition, in the case of the B-PON OLT that supports SNMP (Simple Network Management Protocol) as a management protocol and DBA as a bandwidth control mechanism, it corresponds to Fixed Bandwidth, Assured Bandwidth, and Maximum Bandwidth, which are DBA parameters used in B-PON. An SNMP message template is prepared which includes an object identifier for identifying management information and a part for entering each parameter value. In the element management layer, the correspondence table shown in FIG. 6 is used to hold the relationship between the network element type of each communication method and the element control type included in the network element.
[0037]
The network management layer holds guaranteed bandwidth control information that abstracts a mechanism for performing bandwidth guarantee based on the element control information. The guaranteed bandwidth control information will be described with reference to FIG. The guaranteed bandwidth control information is composed of three modes: an Assured mode, a Policed mode, and an Assured / Policed mode. In the Assured mode, the bandwidth is guaranteed by controlling the minimum bandwidth using a network element having the element control type of type A and type C. In the Policed mode, the network element having the type B element control type is used to guarantee the bandwidth by controlling the maximum bandwidth and regulating the traffic flow rate. In the attached attached mode, a network element having a type C element control type is used to guarantee the bandwidth by controlling the minimum bandwidth and to control the flow rate of traffic by controlling the maximum bandwidth.
[0038]
Further, the network management layer holds the peak bandwidth control information together with the guaranteed bandwidth control information. The peak bandwidth control information indicates whether the peak bandwidth can be controlled independently of the guaranteed bandwidth as shown in FIG. If possible, hold “true” value, otherwise hold “false” value. Peak bandwidth control is possible with network elements having type B and type C element control types. However, when bandwidth is guaranteed using the guaranteed bandwidth control information in the policed mode and the attached-attached-polished mode, the peak bandwidth is controlled independently of the guaranteed bandwidth because the maximum bandwidth control is used. Is impossible. The peak bandwidth control information is determined based on the element control information and the guaranteed bandwidth control information. Further, the network management layer holds a service quality class in combination with guaranteed bandwidth control information in order to guarantee bandwidth and respond to a line delay request.
[0039]
With reference to FIG. 9, the guaranteed bandwidth control information, peak bandwidth control information, and service quality class holding means in the network management layer will be described. The termination point of the connection corresponds to a logical port in the network interface of the network element. In order to perform bandwidth control in units of logical ports, guaranteed bandwidth control information and peak bandwidth control information are held in units of termination points of connections constituting a trail. Furthermore, in combination with guaranteed bandwidth control information and peak bandwidth control information, element control types that support these are also stored in units of connection termination points. At the termination point in the network element where bandwidth control is impossible, the guaranteed bandwidth control information and the element control type hold the value “none”. Even when the bandwidth control is possible, if the control is not performed according to the network operation policy, the none value can be held. The guaranteed bandwidth control information and the peak bandwidth control information are also stored in units of trails as information indicating characteristics related to the bandwidth control of the trail, such as whether the bandwidth can be guaranteed or whether the peak bandwidth can be controlled.
[0040]
The guaranteed bandwidth control information held in the trail unit is determined by combining the guaranteed bandwidth control information held in the connection end point unit. As for the guaranteed bandwidth control information, except for the none value, in the case of the Asserted mode, the bandwidth guarantee of the trail is realized by the control of the minimum bandwidth, so the value in the trail that combines them is also set to the Guaranteed mode. In the case where one or more of the Policed mode and the Attached Policed mode are included, the maximum bandwidth of the trail is controlled and the traffic flow rate is regulated. Therefore, the value in the trail combining these is set to the Poiced mode. If all values are none, the guaranteed bandwidth control information for the trail is none. This indicates that bandwidth control regarding the guaranteed bandwidth is impossible for the trail.
[0041]
Regarding the peak bandwidth control information in the trail, when the guaranteed bandwidth control mode in the trail is not the Policed mode, that is, in the Assured mode, and the true value is included in the peak bandwidth control information at the termination point of the connection constituting the trail, The peak bandwidth control information in the trail is true. When the trail peak bandwidth control information is false, this indicates that bandwidth control regarding the peak bandwidth is impossible for the trail.
[0042]
In FIG. 9, as an example, the output port of the network element 101 supports a band control mechanism of element control type: type C, and the output port of the network element 102 supports a band control mechanism of element control type: type A. The case where the band control mechanism of the element control type: type B is supported at the input port of the element 103 is shown. Therefore, in connection 111, the element control type related to aTP is type C, and in connection 112, the element control type related to aTP is type A, and the element control type related to zTP is type B. Further, in connection 111, a case is considered in which the guaranteed bandwidth control is performed using the minimum bandwidth control mechanism and the peak bandwidth control is performed using the maximum bandwidth control mechanism among the functions of the element control type: type C of aTP. The guaranteed bandwidth control information related to aTP is assumed mode, and the peak bandwidth control information is true. Since zTP is not a control target, guaranteed bandwidth control information is stored as none, and peak bandwidth control information is stored as false. In connection 112, the guaranteed bandwidth control is performed using the aTP element control type: type A minimum bandwidth control mechanism, and the peak bandwidth control is performed using the zTP element control type: type B maximum bandwidth control mechanism. Since the guaranteed bandwidth control information holds the Assured mode for aTP and zTP is not controlled for the guaranteed bandwidth, it holds none, and the peak bandwidth control information is not controlled for the peak bandwidth for aTP. It holds false and zTP holds true since it becomes a control target.
[0043]
In the example of FIG. 9, a trail 120 including a connection 111 and a connection 112 will be described. Since the guaranteed bandwidth control information is in the Assured mode in both the connections 111 and 112, the guaranteed bandwidth control information of the trail 120 that combines them is in the Assured mode. Also. Since the peak bandwidth control information is true in the connections 111 and 112, the peak bandwidth can be controlled by the trail 120, and the peak bandwidth control information of the trail 120 is true.
[0044]
Further, as shown in FIG. 9, the quality of service class is held in the trail and the link. The quality of service class held in the trail represents a delay requirement for the line, that is, a low delay class or a normal delay class. Further, in the link, the physical usable bandwidth value is divided as much as possible, and retained for managing the usable bandwidth value for each service quality class. This is used to determine whether or not the bandwidth is accommodated for each link for each service quality class. The available bandwidth value includes a bandwidth value that can be used as a guaranteed bandwidth and a bandwidth value that can be used as a peak bandwidth.
[0045]
The termination point of the connection corresponds to a logical port in the network interface of the network element, and is used as information for designating a control target when performing network bandwidth control. In order to designate a control target related to bandwidth control for a network element, an ONU number for identifying a network (line), a logical port number, a VLAN-ID, an IEEE 802.1p priority value, a VP identifier, a VC identifier, etc. Network identification information is required. In the element management layer, network identification information for identifying a network (line) in each network element is managed as termination point information. The end point information is stored using a directory service by paying attention to the hierarchical structure.
[0046]
With reference to FIG. 10, the directory structure of the termination point information will be described. In the example of FIG. 10, an entry representing a building has an entry representing a network element. This corresponds to the network element housed in the building. The directory structure is defined according to the equipment management policy. The directory structure under the entry representing the network element is defined according to the communication method supported by the network element.
[0047]
For example, in B-PON, an OLT that is a network element implements one or more PON-IFs (PON interfaces), and one or more ONUs are connected under the PON-IF. In the element management layer, the end point information regarding the B-PON can be retained by defining this hierarchical structure as a directory structure. As shown in the specific example of FIG. 10, the entry representing the B-PON OLT has one or more PON-IF entries as child entries, and the PON-IF entry has one or more ONU entries as child entries. In addition to the hierarchical structure of B-PON, GE-PON has an entry representing a logical port under the ONU entry.
[0048]
In addition, for example, an Ethernet layer 2 switch has an entry representing a physical port under its subordinate, and the physical port entry has a VLAN-ID or an IEEE 802.1p priority value used as a filter condition for identifying traffic. Has an entry representing network identification information.
[0049]
Also, for example, in ATM, an entry representing an ATM switch has an entry representing a physical port. In the case of an ATM switch that switches a VP, an entry representing a VP identifier is included under the physical port entry, and in addition, in the case of an ATM switch that switches a VC, an entry representing the VC identifier is included under the entry representing the VP identifier. Have.
[0050]
The RDN (relative identification name) that identifies each entry in the directory holds a logical name that is logical identification information as a value. Network identification information (PON-IF number, ONU number, physical boat number, VLAN-ID, etc.) for identifying a network (line) corresponding to each entry is held as an attribute value different from RDN. As a result, even when a change such as a building name or NE name is in operation of the directory, only the attribute value holding the network identification information of the corresponding entry needs to be changed, and other management information is affected by the change. Does not spread. In other words, the end point information during operation can be changed in the directory and can be flexibly dealt with.
[0051]
In the network management layer, the connection holds two end point information (aTP and zTP). A means for holding connection termination point information will be described with reference to FIG. The values of aTP and zTP hold the logical end point name as information (logical identification information) for logically identifying the end point. The element management layer has means for converting the logical end point name into a DN (identification name) for uniquely identifying the directory entry. The DN is composed of a series of RDNs. For example, by using the conversion table shown in FIG. 12, the logical termination point name held in the network management layer is converted into the DN of the directory. As a result, even when the directory configuration is changed during operation, it is possible to close the range of the influence to the element management layer, and to maintain the independence of the element management layer and the network management layer.
[0052]
When executing network bandwidth control, a logical termination point name representing a control target of network bandwidth control is distributed from the network management layer to the element management layer. In the element management layer, the logical termination point name is the DN that is an identification name in the directory. Convert to Furthermore, network identification information is acquired from the attribute value of the entry corresponding to each RDN constituting the DN, and these are combined and used as a parameter representing the control target in the bandwidth control request for the network element.
[0053]
As a specific example, a case will be described in which bandwidth control is performed on a B-PON OLT. In B-PON, bandwidth control is executed in units of ONUs. In the network management layer, the logical termination point name corresponding to the ONU is held as the termination point of the connection in the PON section. In the element management layer, a building name, a network element name, a PON-IF number, and an ONU number, which are network identification information for designating an ONU, are stored as attribute values in each entry using a directory. The logical termination point name distributed from the network management layer is converted into a DN representing the corresponding ONU entry. Using this DN, a building name, a network element name, a PON-IF number, and an ONU number are acquired from the ONU entry and each of the entries above it. The building name and network element name are used for designating the network element to be controlled, and the PON-IF number and ONU number are used for designating the control target in the network element.
[0054]
Next, a method for the access network OSS 50 to execute network bandwidth control related to the guaranteed bandwidth for the trail in the network to be managed will be described with reference to the flowchart shown in FIG.
[0055]
The access network OSS 50 first receives a network bandwidth control request from the network administrator or the upper service OSS 70 (step S1-1). Next, with reference to the guaranteed bandwidth control information of the designated trail, it is determined whether bandwidth control relating to the guaranteed bandwidth is possible (step S1-2). At this time, if the guaranteed bandwidth control information is not none, the process proceeds to the next step. Next, the guaranteed bandwidth value of the designated trail is compared with the peak bandwidth value to determine accommodation (step S1-3). At this time, if the guaranteed bandwidth value is equal to or less than the peak bandwidth value, the process proceeds to the next step. Next, the service quality class of the designated trail is acquired (step S1-4). Next, for each link that the specified trail passes, the available bandwidth value of the service quality class of the specified trail and all the trails of the same service quality class as the specified trail among the trails that the link accommodates The sum of guaranteed bandwidth values (including the designated trail) is compared to determine accommodation (step S1-5). Further, the connection constituting the designated trail is acquired (step S1-6), and the guaranteed bandwidth control information held in the terminal unit of each connection is referred to (step S1-7). Then, the termination point to be controlled by the network bandwidth control is determined from the guaranteed bandwidth control information regarding each termination point (step S1-8), and the logical termination point name of the termination point to be controlled and the termination point are retained. The element control type that is the element control information is acquired (step S1-9). At this time, a termination point whose guaranteed bandwidth control information is not none is determined as a control target. Next, an element control request message including a logical termination point name and element control information is created (step S1-10).
[0056]
Here, the element control request message will be described with reference to FIG. The element control request message is created in the control target unit determined in step S1-8. The logical termination point name acquired in step S1-9 is written in the logical termination point name of the element control request message. The element control type acquired in step S1-9 is written in the element control type that is a component of the element control information. A band value and a quality of service class are written in an element control parameter which is another component of the element control information. Regarding the band value, the minimum band value when the element control type is type A, the maximum band value when the element control type is type B, and the minimum band value and the maximum band value when the element control type is type C Write. As for the service quality class, the service quality class acquired in step S1-4 is written.
[0057]
The network bandwidth control will be described with reference to FIG. 13 again. The access network OSS 50 performs processing in the element management layer based on the element control request message created in step S1-10. First, the logical termination point name included in the element control request message is converted into a DN of the directory using the conversion table shown in FIG. 12, and network identification information is obtained from the entries in each layer (step S1-11). At this time, information for identifying the network element to be controlled and the network (line) to be controlled in the network interface of the network element are determined from the network identification information. Further, the bandwidth control mechanism of the network element to be controlled is determined from the element control information included in the element control request message (step S1-12). The bandwidth control mechanism is determined by referring to the correspondence table shown in FIG. 6 from the element control type included in the element control information. Also, an element control message template for controlling the bandwidth control mechanism is acquired from the correspondence table shown in FIG. Then, based on the network identification information acquired in step S1-11 and the bandwidth control mechanism determined in step S1-12, an element control message requested to the network element is determined (step S1-13). The element control message is created according to the bandwidth control mechanism of the network element, the management protocol for controlling the network element, and the management information using the element control message template. Finally, the network element is controlled using the element control message created in step S1-13 (step S1-14).
[0058]
Next, a method for the access network OSS 50 to execute network bandwidth control related to the peak bandwidth for the trail in the network to be managed will be described with reference to the flowchart shown in FIG.
[0059]
The access network OSS 50 first receives a network bandwidth control request from the network administrator or the upper service OSS 70 (step S2-1). Next, with reference to the peak bandwidth control information of the designated trail, it is determined whether bandwidth control regarding the peak bandwidth is possible (step S2-2). At this time, if the peak bandwidth control information is true, the process proceeds to the next step. Next, the peak bandwidth value of the designated trail is compared with the guaranteed bandwidth value to determine accommodation (step S2-3). At this time, if the peak bandwidth value is equal to or greater than the guaranteed bandwidth value, the process proceeds to the next step. Next, the service quality class of the designated trail is acquired (step S2-4). For each link through which the designated trail passes, the available bandwidth value of the designated trail quality of service class is compared with the peak bandwidth value of the designated trail to determine accommodation (step S2-5). Furthermore, the connection which comprises the designated trail is acquired (step S2-6), and the peak band control information hold | maintained in the termination | terminus point unit of each connection is referred (step S2-7). Then, the termination point to be controlled by the network bandwidth control is determined from the peak bandwidth control information regarding each termination point (step S2-8), and the logical termination point name of the termination point to be controlled and the termination point are retained. The element control type which is the element control information is acquired (step S2-9). At this time, a termination point whose peak bandwidth control information is not none is determined as a control target. Next, an element control request message including a logical termination point name and element control information is created (step S2-10). The element control request message is created in the control target unit determined in step S2-8. The logical termination point name acquired in step S2-9 is written in the logical termination point name of the element control request message. The element control type acquired in step S2-9 is written in the element control type that is a component of the element control information. A band value and a quality of service class are written in an element control parameter which is another component of the element control information. As for the service quality class, the service quality class acquired in step S2-4 is written.
[0060]
Next, the element management layer performs processing based on the element control request message created in step S2-10. First, the logical termination point name included in the element control request message is converted into a DN of the directory using the conversion table shown in FIG. 12, and network identification information is acquired from the entries in each layer (step S2-11). At this time, information for identifying the network element to be controlled and the network (line) to be controlled in the network interface of the network element are determined from the network identification information. Further, the bandwidth control mechanism of the network element to be controlled is determined from the element control information included in the element control request message (step S2-12). The bandwidth control mechanism is determined by referring to the correspondence table shown in FIG. 6 from the element control type included in the element control information. Also, an element control message template for controlling the bandwidth control mechanism is acquired from the correspondence table shown in FIG. Then, based on the network identification information acquired in step S2-11 and the bandwidth control mechanism determined in step S2-12, an element control message requested to the network element is determined (step S2-13). The element control message is created according to the bandwidth control mechanism of the network element, the management protocol for controlling the network element, and the management information using the element control message template. Finally, the network element is controlled using the element control message created in step S2-13 (step S2-14).
[0061]
In such a system, when the network management system supports a new network element, the bandwidth control mechanism included in the network element is associated with the element control type. Further, the guaranteed bandwidth control information and the peak bandwidth control information are determined based on the element control type associated with the network element, and the termination point to be controlled is determined.
[0062]
As a specific example, a case where MPLS (Multi-Protocol Label Switching) is supported will be described. MPLS has a band control function using RSVP-TE (Resource Reservation Protocol-Traffic Engineering) or CR-LDP (Constrained-based Routing-Label Distribution Protocol) as a signaling protocol. With regard to LSR (Label Switch Router), which is an MPLS network element, a maximum bandwidth control mechanism based on rate-limitation and a minimum bandwidth control mechanism based on GFR are being studied as specific bandwidth control mechanisms. As for the service quality class, implementation of a CoS queue is being studied in order to support Diffserv-aware Traffic Engineering and Diffrover over MPLS.
[0063]
In an MPLS network, network bandwidth control is performed in units of LSP (Label Switch Path) for which an explicit route is specified, and bandwidth control parameters are set along the explicit route using a RSVP-TE or CR-LDP signaling protocol. This is achieved by setting multiple network elements. The bandwidth control parameter includes a bandwidth value corresponding to the maximum bandwidth value or the minimum bandwidth value, and a service quality class. The network bandwidth control in MPLS will be described using the network shown in FIG. 16 as an example. The network shown in FIG. 16 includes network elements 201 to 204 representing LSRs and physical links 211 to 214 connecting them. When performing network bandwidth control for the LSP 221 that passes through the network element 201 → 202 → 204, an explicit route expressed by a permutation of IP addresses set in the input ports of the network elements 202 and 204 is controlled. As described above, RSVP-TE or CR-LDP is set for the network element 201 which is the edge LSR. At this time, a signaling message including a bandwidth control parameter is issued from the network element 201, and settings relating to bandwidth control are performed for the network elements 202 and 204. In the edge LSR, explicit routes are identified using explicit route identifiers.
[0064]
As shown in FIG. 17, the element control type is type B when the LSR has a maximum bandwidth control mechanism by rate-limiting, and the element control type is type A when the minimum bandwidth control mechanism based on GFR is provided. -Type C when both the maximum bandwidth control mechanism based on limiting and the minimum bandwidth control mechanism based on GFR are provided. The quality of service class is associated with a CoS queue implemented to support Diffserv-aware Traffic Engineering and Diffserver over MPLS. Further, the network element to be controlled by the network bandwidth control is the edge LSR. In the directory holding the termination point in the element management layer, a physical port is defined under the network element, and an entry holding an explicit route identifier is defined under the physical port. Further, a termination point corresponding to an entry holding an explicit route identifier is defined as a control target, and bandwidth control is performed in units of LSPs. When network bandwidth control is requested, network bandwidth control is performed using the network bandwidth control method shown in FIGS.
[0065]
As described above, according to the network bandwidth control according to the present embodiment, network elements having various communication methods and bandwidth control mechanisms can be controlled using a unified network bandwidth control method. It is possible to quickly develop and construct a network management system when supporting a network of the system, and to suppress costs related to system development and construction.
[0066]
Although one embodiment of the present invention has been described above, the present invention is not limited to this. For example, in the above embodiment, bandwidth management was performed for the access network in the network environment including the core network and the access network. However, the present invention is not limited to this, and is applicable to any network environment. Is possible.
[0067]
【The invention's effect】
As described above in detail, according to the present invention, since a network element having various communication methods and bandwidth control mechanisms can be controlled using a unified network bandwidth control method, a network with a new communication method can be used. It is possible to quickly develop and construct a network management system when responding to the above, and to suppress costs associated with system development and construction.
[Brief description of the drawings]
FIG. 1 is a diagram explaining terms in the present invention.
FIG. 2 is a system configuration diagram of a network bandwidth control system.
FIG. 3 is a diagram for explaining an example of element control information
FIG. 4 is a diagram illustrating an example of a correspondence relationship between element control information and a bandwidth control mechanism
FIG. 5 is a diagram for explaining the definition of a service quality class
FIG. 6 is a diagram for explaining an example of a correspondence table between network element types and element control types;
FIG. 7 is a diagram for explaining an example of guaranteed bandwidth control information
FIG. 8 is a diagram for explaining an example of peak bandwidth control information
FIG. 9 is a conceptual diagram related to guaranteed bandwidth control information, peak bandwidth control information, and service quality class in the network management layer.
FIG. 10 is a diagram for explaining an example of a directory configuration of termination point information in the element management layer;
FIG. 11 is a diagram for explaining the relationship between termination point information in the network management layer and the element management layer;
FIG. 12 is a diagram for explaining a conversion table between logical termination point names and directory identification names;
FIG. 13 is a flowchart for explaining a network bandwidth control method related to a guaranteed bandwidth.
FIG. 14 is a diagram illustrating an example of an element control request message
FIG. 15 is a flowchart for explaining a network bandwidth control method related to a peak bandwidth;
FIG. 16 is a diagram for explaining MPLS.
FIG. 17 is a diagram for explaining an example of a correspondence relationship between element control information and a band control mechanism when applied to MPLS;
FIG. 18 is a diagram for explaining an ATM network;
FIG. 19 is a diagram for explaining PON;
FIG. 20 is an explanatory diagram of Ethernet and IP networks.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... User terminal, 20 ... Access network, 30 ... Server, 40 ... Core network, 41, 42 ... Edge router, 50 ... Access network OSS, 60 ... Core network OSS, 70 ... Service OSS, 101-103 ... Network element, 111-112 ... connection, 120 ... trail

Claims (2)

In administrator or network bandwidth control method network bandwidth controller for controlling the network elements in a network managed for the control request for guaranteed bandwidth of the line (trail) from the host device,
A line (trail) in a managed network consists of one or more connections separated by network elements,
The network bandwidth controller is
Means for storing element control information that abstracts the bandwidth control mechanism of each network element as management information in the element management layer in units of connection termination points;
As management information in the network management layer, means for storing guaranteed bandwidth control information abstracted from the bandwidth guarantee mechanism determined based on the element control information in connection termination point units and trail units, the element control information, Means for storing peak bandwidth control information determined on the basis of guaranteed bandwidth control information in connection end point units and trail units; means for storing service quality class information in trail units in combination with the guaranteed bandwidth control information;
Means for storing an available bandwidth value for each quality of service class in a link accommodating the connection;
Means for storing a logical termination point name as termination point information of a connection constituting the trail as management information in a network management layer;
Means for storing, as management information in the element management layer, termination point information constituted by network identification information such as a network element, a physical port, and a logical port in a directory hierarchical structure;
Means for storing a network identification information of the hierarchy constituting the termination point information as an attribute of an entry of each hierarchy, using a logical name as a relative identification name representing an entry of each hierarchy constituting the directory;
Means for converting from the logical end point name to the identification name of the directory holding the end point information,
Determining whether or not the guaranteed bandwidth control related to the control request is possible with reference to the guaranteed bandwidth control information stored in the storage unit for the trail specified in the control request;
When the guaranteed bandwidth control is possible, the guaranteed bandwidth control information stored in the termination point unit of the connection constituting the trail is referred to, and the termination point to be controlled by the control request from the guaranteed bandwidth control information Determining the logical termination point name of the termination point to be controlled and the element control information from storage means;
Creating an element control request message using the determined logical termination point name and element control information;
Converting the logical termination point name included in the element control request message into a directory identification name by the conversion means, and obtaining network identification information representing a control target from a storage means;
Determining the bandwidth control mechanism from the element control information;
Determining an element control message to be requested to each network element from the network identification information and the bandwidth control mechanism;
And a step of controlling a network element using the element control message. In the network bandwidth control method network bandwidth controller for controlling the network elements in a network managed for the control request regarding the peak bandwidth of the line (trail) from the administrator or the upper apparatus,
A line (trail) in a managed network consists of one or more connections separated by network elements,
The network bandwidth controller is
Means for storing element control information that abstracts the bandwidth control mechanism of each network element as management information in the element management layer in units of connection termination points;
As management information in the network management layer, means for storing guaranteed bandwidth control information abstracted from the bandwidth guarantee mechanism determined based on the element control information in connection termination point units and trail units, the element control information, Means for storing peak bandwidth control information determined on the basis of guaranteed bandwidth control information in connection end point units and trail units; means for storing service quality class information in trail units in combination with the guaranteed bandwidth control information;
Means for storing an available bandwidth value for each quality of service class in a link accommodating the connection;
Means for storing a logical termination point name as termination point information of a connection constituting the trail as management information in a network management layer;
Means for storing, as management information in the element management layer, termination point information constituted by network identification information such as a network element, a physical port, and a logical port in a directory hierarchical structure;
Means for storing a network identification information of the hierarchy constituting the termination point information as an attribute of an entry of each hierarchy, using a logical name as a relative identification name representing an entry of each hierarchy constituting the directory;
Means for converting from the logical end point name to the identification name of the directory holding the end point information,
Determining whether the peak bandwidth control related to the control request is possible with reference to the peak bandwidth control information stored in the storage means for the trail specified in the control request;
When the peak bandwidth control is possible, the peak bandwidth control information stored in the unit of the termination point of the connection constituting the trail is referred to, and the termination point to be controlled by the control request from the peak bandwidth control information Determining the logical termination point name of the termination point to be controlled and the element control information from storage means;
Creating an element control request message using the determined logical termination point name and element control information;
Converting the logical termination point name included in the element control request message into a directory identification name by the conversion means, and obtaining network identification information representing a control target from a storage means;
Determining the bandwidth control mechanism from the element control information;
Determining an element control message to be requested to each network element from the network identification information and the bandwidth control mechanism;
And a step of controlling a network element using the element control message.

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