Abstract:
A router particularly providing a P2P traffic supporting router which discriminates and effectively controls P2P (Peer to Peer) traffic transmitted in a network. The router comprises a router part to execute a router function, a discrimination part to discriminate P2P traffic from input traffic, an assignment part to assign discrimination information to the P2P traffic discriminated in the traffic discrimination part, a notification part to create notification information to notify the discrimination information to other routers, and a controller to control the discriminated P2P traffic, wherein the router part outputs the notification information according to directions from the notification part and outputs P2P traffic containing the discrimination information according to directions from the controller.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to a router, and particularly relates to a router which identifies and controls P2P (Peer to Peer) traffic transmitted in networks and a P2P traffic information sharing system using the router.  
         [0003]     2. Description of the Related Art  
         [0004]     As the broad-band Internet has become popular, various P2P applications to exchange files through the Internet among the end users have appeared. A P2P application is file exchange software which enables the exchange of files, among client PCs, directly through the Internet.  
         [0005]     For example, there is a P2P application specialized in specific files or a P2P application to enable exchange of any file without setting a server for file searching or file exchanging on the Internet (see Reference 1). The P2P application enables electronic commerce through the Internet with a third party in an individual level and also enables direct exchange of a large file, e.g., a music data file, etc., among individuals who can access the Internet.  
         [0006]     Reference 1: Japanese Unexamined Patent Publication No. 2003-67276  
         [0007]     However, at present, P2P traffic using the P2P application occupies a large part of the network bandwidth provided by a service provider (ISP) and consequently, use of other web services is restricted. This is because P2P traffic is generally used for a data transmission of a large file such as a music data.  
         [0008]      FIG. 1  shows a comparative example of the P2P traffic and the traffic of other web services or the like.  
         [0009]     As shown in  FIG. 1 , the P2P traffic occupies 70% to 80% of the network bandwidth provided by the service provider, and common Internet applications such as web browsing, and e-mail use only the remaining 20% to 30%.  
         [0010]     Accordingly, P2P causes a congestion in the network and this brings about a degradation of the service quality of the entire network provided by the Internet provider. Moreover, this causes a problem that an equitable service cannot be provided to those who use P2P applications and those who do not use P2P applications.  
         [0011]     In order to eliminate the above problems, the service provider arranges network devices to control the P2P traffic appropriately depending on the traffic volume. The network device must analyze the packet data of upper layers to determine the P2P traffic, therefore, network devices for P2P which can determine P2P traffic have been used.  
         [0012]     Because the network device used for P2P requires more processes to discriminate the P2P traffic than the prior router, its data transmission ability is too small to use as a core in a large scale network. Therefore, the network devices have been used only at specific points in the network, corresponding to data transmission processibility. In order to effectively control P2P traffic in the entire network, it is necessary to provide network devices for P2P, corresponding to the respective traffic capacities, at all the required points in the network.  
         [0013]      FIG. 2  shows an example of a known P2P traffic control.  
         [0014]     In  FIG. 2 , edge routers  31  and  34 , having a function as a network device intended to use for P2P in addition to a function as a router, are placed at reception points in subscriber&#39;s terminals  21  to  24 .  
         [0015]     In practice, the network devices specialized in the P2P are arranged together with the edge routers  31  and  34  having only a router function at the reception points, together with the network devices specialized in the P2P control the P2P traffic. On the other hand, routers  32 ,  33  and  35  in a network  11  with a large amount of traffic only have a function as a router.  
         [0016]     In the present embodiment, only the edge routers  31  and  34  determine the kind of the data stream from subscriber&#39;s terminals  21  to  24  and discriminate the traffic using P2P application (P2P traffic) from the other traffic (Non-P2P traffic). The discriminated p 2 P traffic is, for example, limited in its transmission bandwidth or is discarded if necessary.  
         [0017]     Consequently, the amount of the P2P traffic flowing from the edge routers  31  and  34  into the network  11  is limited whereby congestion in the network  11  due to the P2P traffic is prevented.  
         [0018]     However, even if each P2P traffic flow into the network  11  is restricted in the edge routers  31  and  34 , they are eventually joined in the network  11  when they are sent to an outside network  12 . In this embodiment, the P2P traffic is joined in a router  33  in the network  11  and the joined traffic is sent to the network  12  via an edge router  35  provided at a peering point.  
         [0019]     In this case, the traffic, which is increased due to joining, causes congestion between the router  33  and the edge router  35 , and as a result, the P2P traffic control using the edge routers  31  and  34  does not work effectively. To avoid this, not only the edge routers  31  and  34  but all the routers  31  to  35  in the network  11  are required to have a function of a P2P-specialized network device or to be provided with the same. However, in this case, the data transmission processability is reduced due to the P2P traffic control in the routers  32 ,  33  and  35  in which the amount of the traffic in the network  11  is large.  
       SUMMARY OF THE INVENTION  
       [0020]     The present invention is intended to provide a P2P traffic supporting router and a P2P traffic information sharing system using the router which can discriminate P2P traffic without additionally providing a network device exclusive for P2P and can control P21P traffic in a network without reducing the transmission processability.  
         [0021]     According to the present invention, there is provided a router comprised of a router part to perform a router function, a discrimination part to discriminate P2P traffic from input traffic, an assignment part to assign identification information to the P2P traffic discriminated in the traffic discrimination part, a notification part to create notifying information to notify the discrimination information to other routers, and a controller to control the discriminated P2P traffic, wherein the router part outputs the notifying information according to directions from the notification part and outputs P2P traffic including the discrimination information according to directions from the notification part.  
         [0022]     According to the present invention, there is provided a router comprising 
        a router part to execute a router function, a table to store discrimination information of P2P traffic notified from other router, a determination part to determine that when the discrimination information of the P2P traffic contained in input traffic and discrimination information stored in the table are compared and identical to each other, the traffic is P2P traffic, and a controller to control the P2P traffic, the router part outputting P2P traffic containing the discrimination information according to directions from the controller.        
 
         [0024]     According to the present invention, there is further provided a P2P traffic information sharing system structured as a network comprising the above two kinds of router.  
         [0025]     According to the present invention, if some of the routers can discriminate P2P traffic, the other routers can co-work with the first routers so that P2P traffic can be controlled in the entirety of the network.  
         [0026]     According to the present invention, the some of the routers are placed at a reception point of subscriber&#39;s terminals or the like where the traffic is comparatively light, and therefore, the P2P traffic discrimination can be processed without lowering its router function.  
         [0027]     According to the present invention, each of the routers inside the network controls P2P traffic using mainly an existing router function, so that much traffic can be processed without lowering a data transmission processability as a router. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0028]     The present invention will be more clearly understood from the description as set forth below with reference to the accompanying drawings.  
         [0029]      FIG. 1  shows a comparative example of P2P traffic and another traffic.  
         [0030]      FIG. 2  is a diagram showing an example of a prior P2P traffic control.  
         [0031]      FIG. 3  is a diagram showing an embodiment of a P2P traffic information sharing system according to the present invention.  
         [0032]      FIG. 4  shows a basic structure of a router which can discriminate P2P traffic.  
         [0033]      FIG. 5  shows an example of an operation flow of  FIG. 4 .  
         [0034]      FIG. 6  shows an example of a packet format.  
         [0035]      FIG. 7  shows a basic structure of a P2P discrimination information receiving router.  
         [0036]      FIG. 8  shows an example of a P2P discrimination information table of  FIG. 7 .  
         [0037]      FIG. 9  shows an example (1) of an operation flow of  FIG. 7 .  
         [0038]      FIG. 10  shows an example (2) of an operation flow of  FIG. 7 .  
         [0039]      FIG. 11  is a diagram showing an operation ( 1 ) of a P2P traffic information sharing system according to the present invention.  
         [0040]      FIG. 12  is a diagram showing an operation ( 2 ) of a P2P traffic information sharing system according to the present invention.  
         [0041]      FIG. 13  is a diagram showing an operation ( 3 ) of a P2P traffic information sharing system according to the present invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0042]      FIG. 3  is a diagram showing a structure of a P2P traffic information sharing system, according to the present invention, by way of example.  
         [0043]     The system structure of  FIG. 3  is basically the same as a aforementioned structure shown in  FIG. 2 , and the same numerals are given to object identical to each other, and they will not be explained.  
         [0044]     Hereinafter, a P2P traffic discriminatable router (edge routers  31  and  34  in the drawing), which is one of the significant features of the present invention, and a P2P discrimination information receiving router (internal routers  36  to  38  in the drawing) will be explained. All the routers  31  and  34  to  38  can be equipped with a P2P discrimination information receiving function.  
         [0045]      FIG. 4  shows a basic structure of a P2P traffic discriminatable router.  FIG. 5  shows an example of an operation flow of  FIG. 4 .  
         [0046]     The P2P traffic discriminatable router corresponds to the edge routers  31  and  34  in  FIG. 3  and is provided at a terminal containing point of a provider subscriber where the traffic is comparatively light because not only the original router function but also P2P traffic discriminating process are carried out. In  FIG. 4 , blocks  42 ,  43 ,  46  and  47  relating to the operation of the present invention are clearly indicated by double frames. In  FIG. 5 , the flow of the traffic is shown as a solid line arrow and the flow of discrimination information is shown as a broken line arrow.  
         [0047]     In  FIG. 4 , the traffic from the subscribers terminal  21  and  22  is terminated in a termination  41  (S 01  and S 02 ), and the kind of the traffic is identified in a traffic discrimination part  42  (S 03 ). The traffic discrimination part  42  performs classifying operations for every traffic flow and if the flow of a traffic is classified into P2P traffic, the flow information is registered in a P2P traffic flow table  46  (S 04 ).  
         [0048]     To discriminate the P2P traffic, an upper layer of a received packet data can be analyzed, a communication sequence specific to a P2P communication can be detected, traffic volume which tends to be heavy for P2P traffic can be detected, or a combination thereof can be used.  
         [0049]     Next, an assignment part  43  assigns discrimination information to each packet of the P2P traffic to show that the packet is for the P2P traffic (S 05 ), with reference to the flow information registered in the P2P traffic flow table  46 . This discrimination information includes details of P2P traffic process (for example, transmission priority). This discriminative information may be registered with the corresponding flow information in the P2P traffic flow table  46 .  
         [0050]     The P2P discrimination information notification part  47  refers to the flow information registered in the P2P traffic flow table  46  and obtains the corresponding discrimination information therefrom or from the discrimination information assignment part  43 . Next, a discrimination information notifying packet including the discrimination information is created (S 06 ), and is sent to the internal routers  36  to  38  in the network  11  via a communication controller  44  and an interface termination  45 .  
         [0051]      FIG. 6  shows a typical packet format. For example, the discrimination information is put in the “Type of Service (8 bits)” field. In this case, the internal routers  36  to  38  can receive the discrimination information notifying packet by an existing packet transmission process and no particular process therefor is necessary. A particular communication protocol may be used for this notification and receipt.  
         [0052]     The communication controller  44  determines each output interface for the Non-P2P traffic packet from the traffic discrimination part  42 , the P2P packet from the discrimination information assignment part  43 , or the discrimination information notifying packet from the P2P discrimination information notifying part  47 , based on a predetermined policy (regarding the transmission priority or discard priority for each packet type or the like) and a routing table (not shown), and sends the packets into the network  11  via the interface termination  45  (S 07  and S 08 ). The predetermined policy is given by a device controller  48 .  
         [0053]     In the present example, the P2P traffic discriminatable routers  31  and  37  are provided at reception points of subscriber&#39;s terminals in which the amount of the traffic is comparatively light, and therefore, a processing load to discriminate the P2P traffic hardly affect the data transmission processability as a router. The P2P traffic discriminatable router works together with P2P discrimination information receiving router, which will be discussed hereinafter to thereby control the P2P traffic in the network  11  appropriately, and achieves an effective data transmission in the entire of the network  11 .  
         [0054]      FIG. 7  shows the basic structure of the P2P discrimination information receiving router.  FIG. 8  shows an example of a P2P discrimination information table  52  and  FIG. 9  shows an example of an operation flow in  FIG. 7 .  
         [0055]     The P2P discrimination information receiving router corresponds to the internal routers  36  to  38  and executes inherent router functions, except for an additional simple process for determination of the traffic type and, therefore, the packet transmission process cannot be interrupted in the network  11  where the traffic is heavy.  
         [0056]     In  FIG. 7 , the traffic determination part  51  and the P2P discrimination information table  52 , which especially relate to operations according to the present invention are indicated by double frames, and the following discussion will be mainly addressed to these components. The other components are identical to those corresponding in  FIG. 4 .  
         [0057]     In  FIG. 7 , the traffic from the P2P traffic discriminatable router is terminated in the interface termination  41  (S 11  and S 12 ) and its traffic type is determined in the traffic determination part  51 . In this step, first, it is determined whether the received traffic packet is a discrimination information notifying packet or not (S 13 ). If the packet is the discrimination information notifying packet, the notification content is added to a new entry in the P2P discrimination information table  52  or existing corresponding entry is updated (S 18 ).  
         [0058]     On the other hand, if the packet is not the discrimination information notifying packet, it is determined whether the received traffic is P2P traffic or not with reference to the P2P discrimination information table  52  (S 14 ).  
         [0059]      FIG. 8  shows an example of the P2P discrimination information table  52 . Other identification information such as a predetermined label applied at a predetermined position of packet data may be used.  
         [0060]     As described above, the received discrimination information notifying packet includes not only determination information for each packet of the P2P traffic but also processing details of the packet. An IP address of the P2P traffic discriminatable router  31  or  34 , a source of the discrimination information, an IP address and a port number of the source subscriber&#39;s terminal, an IP address and a port number of the destination subscriber&#39;s terminal, transmission priority of the received P2P traffic, and a time stamp when the corresponding entry is made, are registered in the P2P discrimination information table  52  in  FIG. 8 .  
         [0061]     In the traffic determination part  51 , the P2P discrimination information table  52  is referred to. If discrimination information corresponding to discrimination information added to the received packet from the table is detected, it is immediately determined that the discrimination information is P2P traffic (S 14 ), without analyzing the packet data of the upper layer as in the prior art. Usually the data transmission process is executed without a particular restriction, as in the non-P2P traffic. If a congestion state is detected, the data transmission priority of the P2P traffic is reduced (S 15 ), according to the priority in the table (See  FIG. 8 ).  
         [0062]     On the other hand, if the traffic determination part  51  detects no discrimination information corresponding to the discrimination information added to the received packet, even with reference to the P2P discrimination information table  52 , the traffic is determined to be non-P2P traffic, and the output interface is determined by a normal process (S 17 ). Both the P2P traffic and the non-P2P traffic are sent into the network  11  via the interface termination  45  under control of the communication controller  44  (S 16 ).  
         [0063]     As described above, the load for determining the P2P traffic in the P2P discrimination information receiving router is remarkably small and, hence, the same data transmission capability as that of the existing router can be achieved. Moreover, the P2P traffic in the network  11  can be appropriately controlled so that a very effective data transmission can be achieved in an entire network.  
         [0064]     FIGS.  11  to  13  illustrate operations of P2P traffic information sharing system using a P2P traffic supporting router according to the present invention. The operation of each of the router is as explained above. Therefore, only the operation of the entirety of the P2P traffic information sharing system will be briefly explained here.  
         [0065]     In  FIG. 11 , non-P2P traffic from the subscriber&#39;s terminal  21  and P2P traffic from the subscriber&#39;s terminal  22  are input into the P2P traffic discriminatable router  31 . In the P2P traffic discriminatable router  31 , the traffic discrimination part  42  discriminates the input packet type and only the P2P traffic is registered to the P2P traffic flow table  46 . And, the assignment part  43  assigns the discrimination information to the discriminated P2P traffic.  
         [0066]     In  FIG. 12 , the P2P discrimination information notification part  47  in the P2P traffic discriminatable router  31  refers to the P2P traffic flow table  46  and creates a discrimination information notifying packet based on the discrimination information assigned by the assignment part  43 . The P2P traffic discriminatable router  31  broadcasts the packet to all the routers in the network  11 , to other routers  34 ,  36  to  38  and  35  including P2P traffic discriminatable router and P2P discrimination information receiving routers.  
         [0067]     The P2P discrimination information receiving routers  36  to  38  register the received discrimination information to their P2P discrimination information table  52 . The remaining routers, the P2P traffic discriminatable router  34  and the edge router  35  at a peering point, may be also provided with the P2P discrimination information table  52  to register the received discrimination information.  
         [0068]     In  FIG. 13 , the P2P traffic discriminatable router  31  sends both non-P2P traffic and P2P traffic to the P2P discrimination information receiving routers  36  based on its routing table. The P2P discrimination information receiving routers  36  determines the traffic containing the discrimination information to be P2P traffic by comparing it with the discrimination information registered in its P2P discrimination information table  52 .  
         [0069]     In this example, when the P2P discrimination information receiving router  36  sends the non-P2P traffic and P2P traffic to the adjacent P2P discrimination information receiving router based on its routing table, it also detects a shortage of the band width of the transmission route. Consequently, the P2P discrimination information receiving router  36  refers to the P2P discrimination information table  5  again to obtain the priority for the P2P traffic ( FIG. 8 ).  
         [0070]     Consequently, the transmission priority for the P2P traffic is degraded. The non-P2P traffic with high priority is straightforwardly sent to the P2P discrimination information receiving router  38  and the P2P traffic with low priority is sent to a detour via the P2P discrimination information receiving router  37 .  
         [0071]     After that, the same processes are repeatedly executed in each of the routers  37  to  38  and  35 , and finally, both non-P2P traffic and P2P traffic are sent to the external network  12  via the edge router  35  provided at a peering point.  
         [0072]     As described above, in a P2P traffic information sharing system according to the present invention, P2P traffic is discriminated by only an edge router in which a traffic is comparatively light, and the other routers only execute a simple determination process of discrimination information. Consequently, the P2P traffic can be properly controlled in the entirety of the network and a decrease of data transmission processability of the network can be prevented.