Communication resource management method and node control device using priority control and admission control

Abstract

A communication resource management scheme capable of guaranteeing the communication quality with respect to the flow while not requiring the processing for each flow to nodes other than edge nodes is disclosed. The edge node stores an information for obtaining an available amount of communication resources that can be newly allocated in the network to one set of flows which share at least a route from that edge node to an egress node of the network. Then, the edge node carries out an admission control by newly receiving a request for allocation of communication resources for one flow belonging to that one set of flows, judging whether or not to accept the request according to a requested amount of communication resources and the available amount of communication resources as obtained from the information stored for that one set of flows, and allocating requested communication resources to that one flow when it is judged that the request is to be accepted, while the edge node and the core node carry out the priority control.

What is claimed is:  
     
         1 . A method for managing communication resources in a network containing edge nodes located at a boundary of the network and core nodes located inside the network, comprising the steps of: 
 (a) storing at one edge node an information for obtaining an available amount of communication resources that can be newly allocated in the network to one set of flows which share at least a route from said one edge node to an egress node of the network;    (b) carrying out an admission control at said one edge node by newly receiving a request for allocation of communication resources for one flow belonging to said one set of flows, judging whether or not to accept the request according to a requested amount of communication resources and the available amount of communication resources as obtained from the information stored at the step (a) for said one set of flows, and allocating requested communication resources to said one flow when it is judged that the request is to be accepted; and    (c) transmitting packets at said one edge node by describing a priority level in each packet according to an amount of communication resources allocated to a flow of the packets at the step (b), such that a core node carries out a transfer processing with respect to received packets according to the priority level described in each received packet.    
     
     
         2 . The method of  claim 1 , wherein at the step (b), said one edge node obtains the available amount of communication resources from a prescribed amount of communication resources that can be allocated to each set of flows which was set up in advance so as to satisfy a prescribed communication quality, and an allocated amount of communication resources that is already allocated to said one flow.  
     
     
         3 . The method of  claim 1 , further comprising the step of: 
 (d) sending a notification of the available amount of communication resources to said one edge node by exchanging messages among nodes on the route from said one edge node to the egress node of the network, such that said one edge node stores the information according to the notification at the step (a).    
     
     
         4 . The method of  claim 3 , wherein the step (d) further comprises the sub-steps of: 
 (d1) transmitting from said one edge node an allocated resource notification regarding an amount of communication resources allocated to said one set of flows which include said one flow and which share at least a route from said one edge node to the egress node of the network, according to an amount of communication resources allocated to said one flow;    (d2) sequentially transmitting a remaining resource notification regarding a remaining amount of communication resources that can be newly allocated to some set of flows at each node, which is obtained according to the allocated resource notification transmitted from said one edge node and a transfer capability of said each node, from the egress node through any intermediate core codes, toward an upstream side of said one set of flows; and    (d3) obtaining at said one edge node an available amount of communication resources that can be newly allocated in the network to said one set of flows, according to the remaining resource notification received from a neighboring core node on a downstream side of said one set of flows.    
     
     
         5 . The method of  claim 3 , wherein the step (d) further comprises the sub-steps of: 
 (d1) transmitting from said one edge node an allocated resource notification regarding an amount of communication resources allocated to said one set of flows which include said one flow and which share at least a route from said one edge node to the egress node of the network;    (d2) sequentially transmitting a remaining resource notification regarding a remaining amount of communication resources that can be newly allocated to said one set of flows at each node, which is obtained at said each node according to the amount of communication resources allocated to said one flow by said one edge node or the allocated resource notification transmitted from said one edge node and a transfer capability of said each node, from said one edge node through any intermediate core codes, toward a downstream side of said one set of flows; and    (d3) notifying from the egress node to said one edge node an available amount of communication resources that can be newly allocated in the network to said one set of flows, which is obtained according to the allocated resource notification transmitted from said one edge node, a transfer capability of the egress node, and the remaining resource notification received from a neighboring core node on an upstream side of said one set of flows.    
     
     
         6 . The method of  claim 1 , wherein at the step (b), said one edge node interprets a received packet in a resource reservation protocol, and allocates communication resources requested by using the resource reservation protocol to said one flow indicated by the resource reservation protocol; and 
 at the step (c), each core node transfers a resource reservation protocol packet without interpreting the resource reservation protocol packet.    
     
     
         7 . A method for managing communication resources in a network containing edge nodes located at a boundary of the network and core nodes located inside the network, comprising the steps of: 
 (a) carrying out a priority control in which an edge node transmits packets by describing a priority level in each packet according to an amount of communication resources allocated to a flow of the packets, and a core node carries out a transfer processing with respect to received packets according to the priority level described in each received packet;    (b) transmitting from one edge node a notification regarding an amount of communication resources allocated to a set of flows which include one flow and which share at least a route from said one edge node to an egress node of the network, according to an amount of communication resources allocated to said one flow; and    (c) receiving the notification at one core node and calculating an amount of communication resources to be consumed at said one core node according to the notification.    
     
     
         8 . The method of  claim 7 , wherein at the step (c), when said one core node receives more than one of the notification for a plurality of sets of flows which share at least a route from said one core node to the egress node of the network, said one core node transmits another notification regarding an amount of communication resources allocated to another set of flows which share at least a route from said one core node to the egress node of the network, said another set of flows containing said plurality of sets of flows, according to said more than one of the notification.  
     
     
         9 . The method of  claim 7 , further comprising the step of: 
 interpreting a received packet in a resource reservation protocol, and allocating communication resources requested by using the resource reservation protocol to said one flow indicated by the resource reservation protocol, at said one edge node;    wherein at the step (a), each core node transfers a resource reservation protocol packet without interpreting the resource reservation protocol packet.    
     
     
         10 . A method for managing communication resources in a network containing edge nodes located at a boundary of the network and core nodes located inside the network, comprising the steps of: 
 (a) carrying out a priority control in which an edge node transmits packets by describing a priority level in each packet according to an amount of communication resources allocated to a flow of the packets, and a core node carries out a transfer processing with respect to received packets according to the priority level described in each received packet;    (b) transmitting from one edge node an allocated resource notification regarding an amount of communication resources allocated to one set of flows which include one flow and which share at least a route from said one edge node to an egress node of the network, according to an amount of communication resources allocated to said one flow;    (c) sequentially transmitting a remaining resource notification regarding a remaining amount of communication resources that can be newly allocated to some set of flows at each node, which is obtained according to the allocated resource notification transmitted from said one edge node and a transfer capability of said each node, from the egress node through any intermediate core codes, toward an upstream side of said one set of flows; and    (d) obtaining at said one edge node an available amount of communication resources that can be newly allocated in the network to said one set of flows, according to the remaining resource notification received from a neighboring core node on a downstream side of said one set of flows.    
     
     
         11 . The method of  claim 10 , wherein at the step (c), the egress node transmits the remaining resource notification regarding the remaining amount of communication resources that can be newly allocated at the egress node to some set of flows, which is obtained according to the allocated resource notification transmitted from said one edge node and a transfer capability of the egress node, and each intermediate core node transmits the remaining resource notification regarding the remaining amount of communication resources that can be newly allocated on one route from said each intermediate core node to the egress node, to another set of flows which share at least said one route, which is obtained according to the allocated resource notification transmitted from said one edge node, a transfer capability of said each intermediate core node, and the remaining resource notification received from a neighboring node on the downstream side of said one set of flows.  
     
     
         12 . The method of  claim 10 , wherein at the step (c), each intermediate core node transmits the remaining resource notification while updating the remaining resource notification received from a neighboring node on the downstream side of said one set of flows according to a transfer capability of said each intermediate core node.  
     
     
         13 . The method of  claim 10 , further comprising the step of: 
 interpreting a received packet in a resource reservation protocol, and allocating communication resources requested by using the resource reservation protocol to said one flow indicated by the resource reservation protocol, at said one edge node;    wherein at the step (a), each core node transfers a resource reservation protocol packet without interpreting the resource reservation protocol packet.    
     
     
         14 . A method for managing communication resources in a network containing edge nodes located at a boundary of the network and core nodes located inside the network, comprising the steps of: 
 (a) carrying out a priority control in which an edge node transmits packets by describing a priority level in each packet according to an amount of communication resources allocated to a flow of the packets, and a core node carries out a transfer processing with respect to received packets according to the priority level described in each received packet;    (b) transmitting from one edge node an allocated resource notification regarding an amount of communication resources allocated to one set of flows which include one flow and which share at least a route from said one edge node to an egress node of the network;    (c) sequentially transmitting a remaining resource notification regarding a remaining amount of communication resources that can be newly allocated to said one set of flows at each node, which is obtained at said each node according to the amount of communication resources allocated to said one flow by said one edge node or the allocated resource notification transmitted from said one edge node and a transfer capability of said each node, from said one edge node through any intermediate core codes, toward a downstream side of said one set of flows; and    (d) notifying from the egress node to said one edge node an available amount of communication resources that can be newly allocated in the network to said one set of flows, which is obtained according to the allocated resource notification transmitted from said one edge node, a transfer capability of the egress node, and the remaining resource notification received from a neighboring core node on an upstream side of said one set of flows.    
     
     
         15 . The method of  claim 14 , wherein at the step (c), said one edge node transmits the remaining resource notification regarding the remaining amount of communication resources that can be newly allocated at said one edge node to said one set of flows, according to the amount of communication resources allocated to said one flow by said one edge node, and each intermediate core node transmits the remaining resource notification regarding the remaining amount of communication resources that can be newly allocated to said one set of flows between said one edge node and said each intermediate core node, which is obtained according to the allocated resource notification transmitted from said one edge node, a transfer capability of said each intermediate core node, and the remaining resource notification received from a neighboring node on the upstream side of said one set of flows.  
     
     
         16 . The method of  claim 14 , wherein at the step (c), each intermediate core node transmits the remaining resource notification while updating the remaining resource notification received from a neighboring node on the upstream side of said one set of flows according to a transfer capability of said each intermediate core node.  
     
     
         17 . The method of  claim 14 , further comprising the step of: 
 interpreting a received packet in a resource reservation protocol, and allocating communication resources requested by using the resource reservation protocol to said one flow indicated by the resource reservation protocol, at said one edge node;    wherein at the step (a), each core node transfers a resource reservation protocol packet without interpreting the resource reservation protocol packet.    
     
     
         18 . An edge node device in a network containing edge nodes located at a boundary of the network and core nodes located inside the network, comprising: 
 a memory for storing an information for obtaining an available amount of communication resources that can be newly allocated in the network to one set of flows which share at least a route from said edge node device to an egress node of the network;    an admission control unit for newly receiving a request for allocation of communication resources for one flow belonging to said one set of flows, judging whether or not to accept the request according to a requested amount of communication resources and the available amount of communication resources as obtained from the information stored in the memory for said one set of flows, and allocating requested communication resources to said one flow when it is judged that the request is to be accepted; and    a transmission unit for transmitting packets by describing a priority level in each packet according to an amount of communication resources allocated to a flow of the packets by the admission control unit, toward a core node that carries out a transfer processing with respect to received packets according to the priority level described in each received packet.    
     
     
         19 . An edge node device in a network containing edge nodes located at a boundary of the network and core nodes located inside the network, comprising: 
 a transmission unit for transmitting packets by describing a priority level in each packet according to an amount of communication resources allocated to a flow of the packets, toward a core node that carries out a transfer processing with respect to received packets according to the priority level described in each received packet; and    a notification unit for transmitting a notification regarding an amount of communication resources allocated to a set of flows which include one flow and which share at least a route from said edge node device to an egress node of the network, according to an amount of communication resources allocated to said one flow, such that the core node can calculate an amount of communication resources to be consumed at the core node according to the notification.    
     
     
         20 . A core node device in a network containing edge nodes located at a boundary of the network and core nodes located inside the network, comprising: 
 a transfer unit for carrying out a transfer processing with respect to received packets according to a priority level described in each received packet which are transmitted from an edge node by describing a priority level in each packet according to an amount of communication resources allocated to a flow of the packets; and    a calculation unit for receiving a notification regarding an amount of communication resources allocated to a set of flows which include one flow and which share at least a route from the edge node to an egress node of the network, which is notified from the edge node according to an amount of communication resources allocated to said one flow, and calculating an amount of communication resources to be consumed at said core node device according to the notification.    
     
     
         21 . An edge node device in a network containing edge nodes located at a boundary of the network and core nodes located inside the network, comprising: 
 a transmission unit for transmitting packets by describing a priority level in each packet according to an amount of communication resources allocated to a flow of the packets, toward a core node that carries out a transfer processing with respect to received packets according to the priority level described in each received packet;    a notification unit for transmitting an allocated resource notification regarding an amount of communication resources allocated to one set of flows which include one flow and which share at least a route from said edge node device to an egress node of the network, according to an amount of communication resources allocated to said one flow;    a reception unit for receiving a remaining resource notification from a neighboring core node on a downstream side of said one set of flows, the remaining resource notification being regarding a remaining amount of communication resources that can be newly allocated to some set of flows at each node, which is obtained at said each node according to the allocated resource notification transmitted from said edge node device and a transfer capability of said each node, and which is sequentially transmitted from the egress node through any intermediate core codes, toward an upstream side of said one set of flows; and    a calculation unit for obtaining an available amount of communication resources that can be newly allocated in the network to said one set of flows, according to the remaining resource notification received from said neighboring core node.    
     
     
         22 . A core node device in a network containing edge nodes located at a boundary of the network and core nodes located inside the network, comprising: 
 a transfer unit for carrying out a transfer processing with respect to received packets according to a priority level described in each received packet which are transmitted from an edge node by describing a priority level in each packet according to an amount of communication resources allocated to a flow of the packets; and    a notification unit for receiving a remaining resource notification from a neighboring node on an upstream side of one set of flows and transmitting the remaining resource notification to a neighboring node on a downstream side of said one set of flows, the remaining resource notification being regarding a remaining amount of communication resources that can be newly allocated to some set of flows at each node, which is obtained at said each node according to an allocated resource notification transmitted from one edge node and a transfer capability of said each node, and which is sequentially transmitted from the egress node through any intermediate core codes, toward the upstream side of said one set of flows.    
     
     
         23 . An edge node device in a network containing edge nodes located at a boundary of the network and core nodes located inside the network, comprising: 
 a transmission unit for transmitting packets by describing a priority level in each packet according to an amount of communication resources allocated to a flow of the packets, toward a core node that carries out a transfer processing with respect to received packets according to the priority level described in each received packet;    a notification unit for transmitting an allocated resource notification regarding an amount of communication resources allocated to one set of flows which include one flow and which share at least a route from said edge node device to an egress node of the network, and a remaining resource notification regarding a remaining amount of communication resources that can be newly allocated to said one set of flows at each node, which is to be obtained at said each node according to an amount of communication resources allocated to said one flow by said edge node device or the allocated resource notification transmitted from said edge node device and a transfer capability of said each node, and which is to be sequentially transmitted from said edge node device through any intermediate core codes, toward a downstream side of said one set of flows; and    a reception unit for receiving from the egress node an available amount of communication resources that can be newly allocated in the network to said one set of flows, which is obtained according to the allocated resource notification transmitted from said edge node device, a transfer capability of the egress node, and the remaining resource notification received by the egress node from a neighboring core node on an upstream side of said one set of flows.    
     
     
         24 . A core node device in a network containing edge nodes located at a boundary of the network and core nodes located inside the network, comprising: 
 a transfer unit for carrying out a transfer processing with respect to received packets according to a priority level described in each received packet which are transmitted from an edge node by describing a priority level in each packet according to an amount of communication resources allocated to a flow of the packets; and    a notification unit for receiving a remaining resource notification from a neighboring node on a downstream side of one set of flows and transmitting the remaining resource notification to a neighboring node on an upstream side of said one set of flows, the remaining resource notification being regarding a remaining amount of communication resources that can be newly allocated to some set of flows at each node, which is obtained at said each node according to an amount of communication resources allocated to one flow belonging to said one set of flows by one edge node or an allocated resource notification transmitted from said one edge node and a transfer capability of said each node, and which is sequentially transmitted from said one edge node through any intermediate core codes, toward the downstream side of said one set of flows.