Network system, control method for the same, and controller

• US 20120023231A1
• Filed: 09/30/2011
• Published: 01/26/2012
• Est. Priority Date: 10/23/2009
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Ueno, Hiroshi
• Granted Patent: US 8,832,272 B2
• Time in Patent Office: Days
• US Class Current: 709/225
• CPC Class Codes: H04L 45/38 Flow based routing

Abstract

In a network system, each server is assigned to at least one relay processing devices. A plurality of switches are arranged in a network and a controller controls the switches. Specifically, the controller designs, in response to a request from a request source switch, a route of a flow from the request source switch to a destination address. Here, the controller refers to assignment information indicating an assignment relationship between servers and relay processing devices to select, as a target, any one relay processing device assigned to a server specified by the destination address, and designs the route so as to include the target. Then, the controller instructs each switch on the designed route to set the flow table such that a packet is forwarded along the designed route.

Claims

1. A network system comprising:

a plurality of servers connected to a network;

a plurality of relay processing devices connected to said network;

a plurality of switches arranged in said network; and

a controller configured to control said plurality of switches,

wherein;

each of said plurality of servers is assigned to at least one of said plurality of relay processing devices;

each of said plurality of relay processing devices performs predetermined processing with respect to a packet to a server assigned to said each relay processing device; and

each of said plurality of switches has a flow table indicating a correspondence relationship between an input source and a forwarding destination of a packet with respect to each flow and forwards a packet received from said input source to said forwarding destination by reference to said flow table,

wherein said controller comprises;

a memory unit;

a route design unit configured to design, in response to a request from a request source switch among said plurality of switches, a route of a flow from said request source switch to a destination address; and

a switch setup unit configured to instruct each switch on said designed route to set said flow table such that a packet of the flow is forwarded along said designed route,

wherein information stored in said memory unit comprises;

network configuration information which indicates a connection state between said plurality of servers, said plurality of relay processing devices and said plurality of switches; and

assignment information which indicates an assignment relationship between said plurality of servers and said plurality of relay processing devices,

wherein said route design unit refers to said assignment information to select, as a target, any one relay processing device assigned to a server specified by said destination address, and

said route design unit refers to said network configuration information to design said route so as to include said target.

2. The network system according to claim 1,

wherein the server specified by said destination address is assigned to two or more relay processing devices among said plurality of relay processing devices, and

said route design unit selects any one of said two or more relay processing devices as said target.

3. The network system according to claim 2,

wherein the information stored in said memory unit further comprises:

load information which indicates respective loads of said plurality of relay processing devices; and

link information which indicates states of links in said network,

wherein said route design unit refers to at least one of said load information and said link information to select an optimum one of said two or more relay processing devices as said target.

4. The network system according to claim 2,

wherein said each relay processing device is a load balancer.

5. The network system according to claim 1,

wherein the server specified by said destination address is assigned to one relay processing device among said plurality of relay processing devices, and

said route design unit selects said one relay processing device as said target.

6. The network system according to claim 5,

wherein said each relay processing device is a fire wall.

7. The network system according to claim 1,

wherein said controller further comprises an assignment management unit configured to update said assignment information in response to addition of a server or a relay processing device.

8. A controller that controls a plurality of switches arranged in a network,

wherein:

a plurality of servers and a plurality of relay processing devices are connected to said network;

each of said plurality of servers is assigned to at least one of said plurality of relay processing devices;

each of said plurality of relay processing devices performs predetermined processing with respect to a packet to a server assigned to said each relay processing device; and

each of said plurality of switches has a flow table indicating a correspondence relationship between an input source and a forwarding destination of a packet with respect to each flow and forwards a packet received from said input source to said forwarding destination by reference to said flow table,

said controller comprising;

a memory unit;

a route design unit configured to design, in response to a request from a request source switch among said plurality of switches, a route of a flow from said request source switch to a destination address; and

a switch setup unit configured to instruct each switch on said designed route to set said flow table such that a packet of the flow is forwarded along said designed route,

wherein information stored in said memory unit comprises;

network configuration information which indicates a connection state between said plurality of servers, said plurality of relay processing devices and said plurality of switches; and

assignment information which indicates an assignment relationship between said plurality of servers and said plurality of relay processing devices,

wherein said route design unit refers to said assignment information to select, as a target, any one relay processing device assigned to a server specified by said destination address, and

said route design unit refers to said network configuration information to design said route so as to include said target.

9. A control method for a network system,

wherein said network system comprises:

a plurality of servers connected to a network;

a plurality of relay processing devices connected to said network; and

a plurality of switches arranged in said network,

wherein;

each of said plurality of servers is assigned to at least one of said plurality of relay processing devices;

each of said plurality of relay processing devices performs predetermined processing with respect to a packet to a server assigned to said each relay processing device; and

each of said plurality of switches has a flow table indicating a correspondence relationship between an input source and a forwarding destination of a packet with respect to each flow and forwards a packet received from said input source to said forwarding destination by reference to said flow table,

wherein said control method comprises;

designing, in response to a request from a request source switch among said plurality of switches, a route of a flow from said request source switch to a destination address; and

instructing each switch on said designed route to set said flow table such that a packet of the flow is forwarded along said designed route,

wherein the designing said route comprises;

reading network configuration information and assignment information from a memory device,

wherein;

said network configuration information indicates a connection state between said plurality of servers, said plurality of relay processing devices and said plurality of switches; and

said assignment information indicates an assignment relationship between said plurality of servers and said plurality of relay processing devices;

selecting, as a target, any one relay processing device assigned to a server specified by said destination address, by reference to said assignment information; and

designing said route so as to include said target, by reference to said network configuration information.