WO2016099368A1 - Activation et distribution de règles de politique dans un réseau de communication - Google Patents

Activation et distribution de règles de politique dans un réseau de communication Download PDF

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Publication number
WO2016099368A1
WO2016099368A1 PCT/SE2014/051555 SE2014051555W WO2016099368A1 WO 2016099368 A1 WO2016099368 A1 WO 2016099368A1 SE 2014051555 W SE2014051555 W SE 2014051555W WO 2016099368 A1 WO2016099368 A1 WO 2016099368A1
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WIPO (PCT)
Prior art keywords
routing
router
protocol message
activation
message
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PCT/SE2014/051555
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English (en)
Inventor
Annikki Welin
Tomas Thyni
Per LINDH MÅNGS
Jan-Erik MÅNGS
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Telefonaktiebolaget Lm Ericsson (Publ)
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Priority to PCT/SE2014/051555 priority Critical patent/WO2016099368A1/fr
Publication of WO2016099368A1 publication Critical patent/WO2016099368A1/fr

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Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L45/00Routing or path finding of packets in data switching networks
    • H04L45/302Route determination based on requested QoS
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W40/00Communication routing or communication path finding
    • H04W40/02Communication route or path selection, e.g. power-based or shortest path routing

Definitions

  • the present technology relates to methods and router elements in a communication network.
  • methods for distributing routing policy rules in radio access transport network, and methods for activation or deactivation of the routing policy rules in said router elements are disclosed.
  • packets are normally forwarded based on their destination address; this is often referred to as destination based routing.
  • a routing table is used to find the path through the network, in each forwarding node, a "best" matching entry is found in its routing table and the packet is sent to the corresponding next-hop address, which is found in the routing table.
  • This routing information is normally provided to each router using routing protocols such as Open Shortest Path First (OSPF), Intermediate System to Intermediate System (IS-IS), Border Gateway Protocol (BGP), or manually configured (static) routing or a combination of these.
  • OSPF Open Shortest Path First
  • IS-IS Intermediate System to Intermediate System
  • BGP Border Gateway Protocol
  • static routing or a combination of these.
  • packets can also be forwarded based on other criteria, such as the source address, protocol type, type of application or other information available in the packet header or payload.
  • policy based routing instead of just using destination addresses, flexible routing policies can define the next-hop for a packet.
  • routing policies typically override the normal destination based routing, so a router typically has a set of policies that are each tested and if no rule is matched, the forwarding is done using ordinary destination based forwarding.
  • Policy rules are typically inserted by manually logging in to each router to enter its configuration or through some operation, administration and management system into each affected router. If the routing of certain data packets has to be changed, other policy rules for said data packets have to be activated and/or inserted, and old policy rules have to be removed or deactivated, the manually procedure has to be repeated. This is considered by some to be a cumbersome and time consuming procedure and probability of human made errors increases. Such errors may result in inconsistency in policy routes between nodes. Inconsistency in policy routes between nodes can lead to traffic being ping-ponged between the nodes.
  • One object is therefore to provide a more effective procedure for updating the routing of data packets by means of routing policy rules.
  • the policy routing is handled by an application linked to a first router element of a Radio Access Transport Network (RATN) and by means of routing policy rules of routing policy sets in second router elements of the RATN.
  • RTN Radio Access Transport Network
  • a method for routing of data packets and embodiments thereof are provided.
  • the method enables routing of data packets by means of routing policy rules of routing policy sets in second router elements of a Radio Access Transport Network.
  • the routing policy rules is controlled by a first router element and an application linked to the first router element of the Radio Access Transport Network.
  • Said method may comprise receiving of a decision from the application to activate or deactivate a routing policy rule stored in the routing policy set of one or more second router elements, selecting at least one routing path comprising the second router elements for which the routing policy rule is to be activated or deactivated, sending one activation or deactivation message along the selected routing path comprising the second router elements for which the routing policy rule of the policy rule set is to be activated or deactivated, and routing and sending data packets handled by the application according to the updated policy rule set.
  • the method may comprise receiving one or more routing policy rules from the application, retrieving actual router element routing state information for the second router elements from a topology database of the Radio Access Transport Network, selecting based on the actual router element routing state information at least one routing path comprising the second router elements for which policy rule sets are to be updated with the one or more routing policy rules, and sending the one or more routing policy rules in a routing protocol message along a selected routing path comprising the second router elements for which the one or more routing policy rules are to be updated.
  • a method for enabling routing of data packets by a second router element of a Radio Access Transport Network by means of routing policy rules of a policy rule set and embodiments of said method are provided.
  • Said Radio Access Transport Network comprises at least one first router element for distributing routing policy rules via selected routing paths comprising the router elements for which the routing policy rule set is to be updated.
  • Said method comprises receiving one activation or deactivation message for activating or deactivating one or more routing policy rules of the policy rule set, activating or deactivating one or more routing policy rules of the policy rule set, routing and sending data packets according to the updated policy rule set.
  • the method may further comprise receiving one or more routing policy rules carried by a routing protocol message, storing the received one or more routing policy rules in the policy rule set, forwarding the routing protocol message comprising the one or more routing policy rules along a preselected routing path comprising the second router elements for which the one or more routing policy rules are to be updated.
  • a router element of a Radio Access Transport Network and embodiments thereof are provided.
  • the router element enables routing of data packets, wherein the routing handled by an application linked to the first router element of a Radio Access Transport Network and by means of routing policy rules of routing policy sets in second router elements of the Radio Access Transport Network.
  • the router element comprises a router controller being adapted to perform receiving a decision from the application to activate or deactivate a routing policy rule stored in the routing policy set of one or more second router elements, selecting at least one routing path comprising the second router elements for which the routing policy rule is to be activated or deactivated, sending one activation or deactivation message along the selected routing path comprising the second router elements for which the routing policy rule of the policy rule set is to be activated or deactivated, and routing and sending data packets handled by the application according to the updated policy rule set.
  • the router element comprising a router controller may further be adapted to perform receiving one or more routing policy rules from the application, retrieving actual router element routing state information for the second router elements from a topology database of the Radio Access Transport Network, selecting based on the actual router element routing state information at least one routing path comprising the second router elements for which policy rule sets are to be updated with the one or more routing policy rules, and sending the one or more routing policy rules in a routing protocol message along a selected routing path comprising the second router elements for which the one or more routing policy rules are to be updated.
  • a router arrangement and embodiments thereof are provided.
  • the router arrangement enables routing of data packets by a second router element of a Radio Access Transport Network by means of routing policy rules of a policy rule set.
  • Said Radio Access Transport Network comprises at least one first router element for distributing routing policy rules via selected routing paths comprising the router elements for which the routing policy rule set is to be updated.
  • Said router arrangement comprising a router controller adapted to perform receiving one activation or deactivation message for activating or deactivating routing one or more routing policy rules of the policy rule set, activating or deactivating one or more routing policy rules of the policy rule set, and routing and sending data packets according to the updated policy rule set.
  • the router arrangement may further comprise a router controller adapted to perform receiving one or more routing policy rules carried by a routing protocol message, storing the received one or more routing policy rules in the policy rule set, and forwarding the routing protocol message comprising the one or more routing policy rules along a pre-selected routing path comprising the second router elements for which the one or more routing policy rules are to be updated.
  • a router controller adapted to perform receiving one or more routing policy rules carried by a routing protocol message, storing the received one or more routing policy rules in the policy rule set, and forwarding the routing protocol message comprising the one or more routing policy rules along a pre-selected routing path comprising the second router elements for which the one or more routing policy rules are to be updated.
  • a program on one router controls the policies of all other routers, opening up new possibilities, such as activating policies as needed (e.g. react to real-time resource usage) or at a set time point.
  • Figure 1 is a block diagram schematically illustrating a communications network
  • Figure 2 is a block diagram of a first set up of an application and first router element:
  • Figure 3 is a block diagram of a second set up of an application and first router element
  • Figure 4 is a block diagram schematically illustrating an alternative communications network
  • Figure 5 is a flowchart illustrating an embodiment of the method S100 comprising two processes S100A and S100B;
  • Figure 6 is a flowchart illustrating a process S100B for activating and deactivating routing policy rules
  • Figure 7 is a flowchart illustrating a process SI OOA for distributing routing policy rules to the router elements of a RATN;
  • Figure 8 is a flowchart illustrating an embodiment of the method S200 comprising two processes S200A and S200B;
  • Figure 9 is a flowchart of a process S200B of handling activation and deactivation messages by a second router element
  • Figure 10 is a flowchart illustrating the process S200A
  • Figure 1 1 is a block diagram illustrating a router element of a Radio Access Transport Network
  • Figure 12 is a block diagram illustrating another example of a router element
  • Figure 13 is a block diagram illustrating a router arrangement of a Radio Access Transport Network
  • Figure 14 is a block diagram illustrating another example of a router arrangement of a second router element
  • Figure 15 is a block diagram illustrating a routing loop in a network comprising router elements.
  • a method is similar to a process, as both are defined by the steps involved.
  • a process is in itself a method that may be considered as a sub-method of a method.
  • a sub-method involves one or more steps of all the steps of a method.
  • a method may comprise a number of processes, methods or sub-methods which is performed in a predetermined order.
  • a process or sub-method can also be regarded as a stand-alone method, which may be performed without the other sub-methods of a method are performed.
  • a router element comprises a routing and/or switching functionality, such as a router.
  • Radio Access Transport Network is a communications network adapted for transporting and routing/switching data traffic between a node or network, providing radio access functionality and facilities, and a Core Network, CN, or backbone network, which is a central part of a telecommunication network that provides various services to customers connected to said node or network.
  • FIG. 1 is schematically illustrating a communications network comprising a Radio Access Transport Network (RATN) 10, Core Network (CN) 50, and the Internet 60.
  • the communications network is able to connect mobile user equipments (UEs) 70 to any addressed end destination, here illustrated as the Internet 60.
  • Data traffic i.e. the flow of data packets, to or from the UE 70 is forwarded via data paths 12 through different networks from the source having a source address to the end destination address.
  • each path comprises a number of router elements 30, 40 connected via next-hop links 12.
  • an application 20 e.g. a radio base station RBS functionality or other software implemented software functionality for generating or handling data packets, is connected to a router element 30 for routing the data traffic either path.
  • the RBS 20 and/or the router element 30 may have access to a metrics database 28 comprising different metrics regarding the hop links 12 and router elements of the RATN.
  • the routing may be based on different features or criteria of which one is routing based on policy rules, which is the routing technique of interest in the following disclosure.
  • Policy based routing means that instead of just using destination addresses, flexible routing policies can define the next- hop for a packet. For example, assume two different applications transmit data from a node comprising a Radio Base Station 20 to node comprising a PDN-GW (Packet Data Network Gateway) 52 over some intermediate network RATN 10 and CN 50.
  • PDN-GW Packet Data Network Gateway
  • policy based routing permits the routing of these packets over two different network paths, 12' and 12" in figure 1 , through the RATN to the CN 50. Destination based routing would not allow different network paths since the destination addresses are the same for both applications. Routing policies typically override the normal destination based routing, so a router typically has a set of policies that are each tested and if no rule is matched, the forwarding is done using ordinary destination based forwarding.
  • TCP Transport Control Protocol
  • Said routing policy rules are stored in the router elements 30, 40, or in connection to said router elements.
  • a Global Policy Database, GPDB, 24 comprises all available routing policy rules from which routing policy rules are selected for the sets of policy rules stored in Local Policy Databases, LPDBs, 26 and used by the router elements 40. These sets of policy rules may contain the same routing policy rules or different policy rules.
  • An OSPF network topology database TDB 22 stores network topology information about the network, e.g. router element routing information.
  • Network topology is the arrangement of the various elements, e.g. links, nodes, etc., of a communication network. Essentially, it is the topological structure of a network and may be depicted physically or logically. Physical topology is the placement of the various components of a network, including device location and cable installation, while logical topology illustrates how data flows within a network, regardless of its physical design. Distances between nodes, physical interconnections, transmission rates, or signal types may differ between two networks, yet their topologies may be identical. According to prior art, and in order to enable policies to be stored in the elements of existing networks, it has been necessary to login in each network element e.g. router. This is considered by some to be a cumbersome and time consuming procedure and probability of human made errors increases. To be able to bring down the OPEX, it is therefore hereafter described a solution to automate O&M of storing routing policy rules in different networks element.
  • Methods are provided herein, which methods enable routing of data packets by means of routing policy rules of routing policy sets in second router elements of a Radio Access Transport Network.
  • the routing policy rules are controlled by a first router element and an application linked to the first router element of the Radio Access Transport Network.
  • By controlling the routing policy rules is meant to distribute and insert policy rules and/or activate and/or deactivate said policy rules.
  • methods are provided comprising a process for activation or deactivation of routing policy rules and/or a process for automatic distribution of routing policy rules.
  • FIGS. 2 and 3 are two implementations illustrated by functional blocks.
  • the two different embodiments are created to enable automatic distribution of policies.
  • the automated distribution and activation of policies is achieved by using none- standard type of Type-Length-Values, TLVs.
  • TLVs Type-Length-Values
  • the policy is inserted in the TLV and the same TLV can be used to activate policies.
  • an I2RS interface is used to distribute the policies, but the activation is done by TLV, that embraces timing aspect to activation.
  • the activation can be scheduled based on the traffic load and characteristics.
  • Figure 2 shows a first set up of functional blocks of an application and first router element.
  • This first implementation comprises an application 20 and first router element 30' connected to second router elements 40'.
  • the first router element 30' comprises a Link State Advertisement (LSA) originator (LSAO) 32 for communicating with each second router element 40' comprising LSA Receiver (LSAR) 42.
  • LSA Link State Advertisement
  • LSAO Link State Advertisement originator
  • LSAR LSA Receiver
  • Type-Length-Value is an often-used way to decode data in communication protocol messages.
  • the Type and Length data is of fixed size, typically 1 -4 bytes, and the size of the Value part is variable and as indicated by the value in the Length field.
  • Open Shortest Path First, OSPF makes extensive use of TLVs in LSAs. Simplified, information can be encoded using TLVs in OSPF "Opaque LSAs" messages and the information is flooded by the OSPF messages between all OSPF enabled router elements in a network via the next-hop links 12, 12', 12". So the OSPF protocol message is sometimes used this way as a "bearer” of new information coded as "TLVs" to routers in a network.
  • the application 20 uses the first router element 30' and gets the network topology from OSPF topology database 22 and it keeps its own global policy database 24 for mapping a set of policies to each router element interface.
  • the application e.g. a Radio Base Station, RBS
  • the LSA contains a list of orders where each order got an OSPF Link ID associated with it.
  • the order may be an activation or deactivation message or an order to update the set of policy rules with enclosed routing policy rules.
  • Each second router element knows its own IDs and can thereby tell which orders are addressed for it. Because the IDs are OSPF Link IDs, the second router elements can also tell which interface to apply the policy.
  • the routing policy rules, activated and deactivated, are stored in the LPDB 26.
  • the LSAR 42 checks if the OSPF Link ID is similar to the ID of the router element 40. If the IDs match, the LSAR 42 is configured to activate or deactivate stored routing policy rules in the LPDB 26 or to insert received new routing policy rules into the stored set of policy rules in the LPDB 26. All router elements of the RATN are synchronized by means of the network's clock synchronization, Clk, functionality.
  • the application e.g. an RBS
  • the network topology may be accompanied by additional data of the network, such as networks metrics 28.
  • Networks metrics may involve e.g. bandwidth and delay/jitter of hop links. This would let a program use this data for choosing an appropriate path.
  • I2RS Routing System
  • Figure 3 shows functional blocks an application and first router element where I2RS interface and synchronization module is included.
  • This second implementation comprises an application and first router element 30" connected to second router elements 40".
  • the first router element 30" comprises a Link State Advertisement (LSA) originator (LSAO) 32 for communicating with each second router element 40" comprising LSA Receiver (LSAR) 42.
  • LSA Link State Advertisement
  • LSAO Link State Advertisement originator
  • LSAR LSA Receiver
  • the application 20 is connected to the first router element 30', but it might as well be integrated with the first router element as in the embodiment illustrated in figure 2.
  • the first router element 30" comprises an Interface to the Routing System Client, I2RSC, 34, for communicating with a corresponding I2RS Agent, I2RSA, 44 in a second router element 40".
  • an I2RS interface comprises an I2RSA, 44, and a I2RS Client, I2RSC, 34.
  • Second router elements 40 are usually not capable of exchanging information as they usually are not provided with an I2RSC.
  • Second router elements 40" with an I2RSC, 46 are able to send information to other second router elements 40 provided with I2RSA.
  • the I2RS interface can be used to distribute routing policies to the network's second router elements 40". The policies are distributed with I2RS, but the activation is using OSPF TLV as in the first embodiment described above.
  • the synchronization module sets date of time to be same in all network elements/nodes, enabling activation of policies happening in synchronized manner.
  • the application uses the first router element 30" and gets the network topology from OSPF topology database 22 and it keeps its own global policy database 24 for mapping a set of policies to each router element interface.
  • the application e.g. an RBS
  • an RBS wants to send an activation or deactivation order, or message, to any router in the network it originates an opaque LSA which distributed through the network by OSPF routing protocol message.
  • the LSA contains a list of orders where each order got an OSPF Link ID associated with it.
  • Each router knows its own IDs and can thereby tell which orders are addressed for it.
  • the routing policy rules, activated and deactivated, are stored in the LPDB 26.
  • an activation or deactivation order/message is received by the LSAR 42, it checks if the OSPF Link ID is similar to the ID of the router element 40. If the IDs match, the LSAR 42 is configured to activate or deactivate stored routing policy rules in the LPDB 26.
  • an I2RS message comprising one or more routing policy rules is sent from a I2RSC 34 and received in an addressed second router element 40" by its I2RSA 44
  • said agent 44 is adapted to insert received new routing policy rules into the stored set of policy rules in the LPDB 26.
  • Said routing policy rules are activated by the OSPF message/order.
  • the application e.g. an RBS
  • the network topology may be accompanied by additional data of the network, such as networks metrics 28.
  • Figure 4 is schematically illustrating a communications network comprising first and second router elements 30", 40". Said router elements are described in the text above referring to figure 3. Corresponding elements and components of the networks in figure 1 and figure 4 have been given the same reference number. Said corresponding elements and components have already been described in the text above in relation to figure 1 .
  • the illustrated network differs in that I2RS interfaces 14 are used to distribute the policies, but the activation and deactivation is done by OSPF TLV that embraces timing aspect to activation.
  • I2RS interfaces 14 allow information, policies, and operational parameters to be injected into and retrieved (as read or by notification) from the routing system.
  • the I2RS interfaces will co-exist with existing configuration and management systems and interfaces. So I2RS can be used to insert policies into routers individually.
  • I2RS is also related to Software Defined Networking, SDN.
  • One advantage with the following described technique is that the risk for routing loops to occur in a routing policy controlled system and network is reduced, if not more or less eliminated.
  • the procedure of activating and distributing policies is automated where decided policies gets activated at the same time in the entire network, thereby avoiding routing loops.
  • FIG. 5 is a flowchart illustrating an embodiment of the method S100 comprising two processes S100A and S100B. Said processes may as stated above also be called methods.
  • Each of the processes S100A and S100B may be performed standalone. The processes may be performed when activated from an application, such as an RBS.
  • the process S100A is triggered in the first router element by the event that one or more routing policy rules are sent from the application and received by the first router element.
  • the process S100B is triggered in the first router element by the reception of activation or deactivation decision from the application.
  • the reception of an activation and/or deactivation decision is another trigger event.
  • the received trigger or trigger event may be a routing policy rule or an activation or deactivation decision sent from the application.
  • the process S100A is performed.
  • the reception of one or more routing policy rules which is triggering the method S100 and process S100A to start may besides said routing policy rules comprise the reception of activation decision for activation of e.g. said received one or more routing policy rules, and/or one or more deactivation decision of a specified routing policy rule in a policy rule set.
  • the process S100A may be tested if an activation decision or deactivation decision has been received. If an activation decision or deactivation decision has not been received, "NO”, the method returns to a stand-by state waiting for the next trigger event. If an activation decision or deactivation decision has been received, "YES", the process S100B is performed and the method returns to a stand-by state waiting for the next trigger event.
  • the method is triggered by a reception event wherein a policy rule is not received, it is tested if an activation or deactivation decision has been received. If not, thus "NO", a false triggering of the method is received and an error alarm is generated and sent to an operation and maintenance site of the network. If an activation or deactivation decision is received, the process S100B is performed and the method returns to a stand-by state waiting for the next trigger event.
  • Figure 6 is a flowchart illustrating a process for activating and deactivating routing policy rules according the herein proposed technique for enabling routing of data packets.
  • the method S100 enables updating the routing policy set of router elements in a Radio Access Transport Network, RATN, comprising a first router element and one or more second router elements.
  • a first router element is a router element comprising features for controlling the update of policy rules of other router elements, i.e. the second router elements.
  • a first router element may be situated in or associated with a Radio Base Station, RBS, or situated in or associated to a node of the RATN, said node being a router element.
  • the method enables routing of data packets by means of routing policy rules of routing policy sets in second router elements of the Radio Access Transport Network.
  • the routing policy rules is controlled by a first router element and an application linked to the first router element of a Radio Access Transport Network.
  • the process S100B is a method for automatically activating and deactivating routing policy rules of routing policy sets in router elements of the RATN. If the application is to send data packets, wherein said data packets are meant to be sent a preferred routing path in the network, the application may control the routing to the correct routing path by activating or deactivating one or more routing rules in one or more second router elements of the network.
  • the routing policy rules of a routing policy set may have been pre-stored in a second router element, either manually or by means of process S100A. Said process is described in more details further down in this description.
  • the process of activating or deactivating routing policy rules comprises:
  • S150 - receiving a decision from the application to activate or deactivate a routing policy rule stored in the routing policy set of one or more second router elements;
  • S160 - selecting at least one routing path comprising the second router elements for which the routing policy rule is to be activated or deactivated;
  • S170 - sending one activation or deactivation message along the selected routing path comprising the second router elements for which the routing policy rule of the policy rule set is to be activated or deactivated;
  • the selection of at least one routing path in S160 can be achieved by retrieving actual router element routing state information for the second router elements from the topology database of the Radio Access Transport Network.
  • S160 may involve flooding of said activation or deactivation message in the communications network along one or more paths.
  • Each routing policy rule of a policy rule set has an identification making it possible to identify and to activate or deactivate said policy rule by means of a router controller (see 410 in figure 1 1 ) of the router element.
  • Said router controller is thus able to recognize an activation message or a deactivation message, retrieve the information of the message, identify the routing policy rule in question and activate or deactivate the rule in the stored policy rule set.
  • the router controller makes use of the routing policy rule during the routing process.
  • a deactivated routing policy rule is not a part of or used in the routing process.
  • the communications network e.g. Radio Access Transport Network
  • the activation or deactivation message comprises time information for activating or deactivating a routing policy rule of a policy rule set in one of each of said one or more router elements.
  • the activation or deactivation message is configured to activate or deactivate a routing policy rule of the policy rule set in a router element direct or essentially simultaneously upon reception of said activation or deactivation message.
  • the activation or deactivation message is preferably a routing protocol message.
  • Different kinds of routing protocol messages are known, but said known protocol messages have to be adapted to be used as activation or deactivation message.
  • two protocol messages are suggested for supporting the process S100B.
  • One routing protocol message to be used is a modified and extended OSPF or IS-IS protocol message comprising a TLV parameter indicating if the routing protocol message is an activation or deactivation protocol message.
  • I2RS interface or a similar protocol, is used to distribute the policies meant for a second routing element directly to that second routing element, but the activation is done by TLV, that embraces timing aspect to activation.
  • the routing protocol message to be used is a hybrid SDN protocol message comprising a parameter indicating if the SDN routing protocol message is an activation or deactivation protocol message.
  • the activation can be scheduled based on the traffic load and characteristics.
  • the application may be a radio base station associated with the first router element.
  • Figure 7 is a flowchart illustrating a process S100A for distributing routing policy rules to the router elements of a communications network, e.g. a RATN.
  • the method S100 may further comprise the process S100A for distributing routing policy rules to the router elements of the communications network.
  • Said process may comprise following steps:
  • S120 - retrieving actual router element routing state information for the second router elements from a topology database of the Radio Access Transport Network;
  • S130 - selecting based on the actual router element routing state information at least one routing path comprising the second router elements for which policy rule sets are to be updated with the one or more routing policy rules;
  • S140 - sending the one or more routing policy rules in a routing protocol message along a selected routing path comprising the second router elements for which the one or more routing policy rules are to be updated.
  • the routing state information comprises information about the topology of the network, e.g. link/path capacities, operation, if a router is on or off, etc.
  • the routing protocol message to be used is a modified and extended OSPF protocol message or IS-IS comprising a TLV parameter.
  • the automated distribution and activation of policies is achieved by using new type of TLVs.
  • the policy is inserted in the TLV and the same TLV can be used to activate policies.
  • the routing protocol message to be used is a hybrid SDN protocol message comprising a parameter indicating if the SDN protocol message is carrying one or more policy rules.
  • Figure 8 is a flowchart illustrating an embodiment of the method S200 comprising two processes S200A and S200B.
  • Each of the processes may be performed stand-alone, but the processes may be performed in a second router element when activated at reception of a protocol message from the first router element .
  • the process S200A is triggered by the event that one or more routing policy rules are sent from the first router element and received by the second router element.
  • the process S200B is triggered in the second router element by the reception of activation or deactivation messages from the first router element.
  • the reception of an activation and/or deactivation message is another trigger event.
  • the received trigger or trigger event S205 may be a routing policy rule or an activation or deactivation message sent from the first router element.
  • the process S200A is performed.
  • the reception of one or more routing policy rules which is triggering the method S200 and process S200A to start may besides said routing policy rules comprise the reception of activation message for activation of e.g. said received one or more routing policy rules, and/or one or more deactivation messages of a specified routing policy rule in a policy rule set.
  • the process S200A may be tested if an activation message or deactivation message has been received. If not an activation message or deactivation message has been received, "NO”, the method returns to a stand-by state waiting for the next trigger event. If an activation message or deactivation message has been received, "YES", the process S200B is performed and the method returns to a stand-by state waiting for the next trigger event.
  • the method is triggered by a reception event wherein a policy rule is not received, it is tested if an activation or deactivation message is received. If not, thus "NO", a false triggering of the method is received and an error alarm is generated and sent to an operation and maintenance site of the network. If an activation or deactivation message is received from the first router element, the process S200B is performed and the method returns to a stand-by state waiting for the next trigger event.
  • Figure 9 is a flowchart of a process S200B of handling activation and deactivation messages by a second router element.
  • the process S200B corresponds to the process S100B in the first router element.
  • the process S200B enables routing of data packets by a second router element of a communications network, e.g. a Radio Access Transport Network, by means of routing policy rules of a policy rule set.
  • a first router element distributes routing policy rules via selected routing paths comprising the router elements for which the routing policy rule set is to be updated.
  • Said process comprises the step of:
  • S240 - receiving one activation or deactivation message for activating or deactivating one or more routing policy rules of the policy rule set;
  • the Radio Access Transport Network is time synchronized, and the activation or deactivation message comprises time information for activating or deactivating a routing policy rule of a policy rule set in one of each of said one or more router elements.
  • the activation or deactivation message is configured to activate or deactivate a routing policy rule of the policy rule set in a router element direct or essentially simultaneously upon reception of said message.
  • the activation or deactivation message is preferably a routing protocol message.
  • Different kinds of routing protocol messages are known, but said known protocol messages have to be adapted to be used as activation or deactivation message.
  • two protocol messages are suggested for supporting the process S200B.
  • One routing protocol message to be used is a modified and extended SDN protocol message comprising a parameter indicating if the SDN protocol message is an activation or deactivation protocol message.
  • the automated distribution and activation of policies is achieved by using new type of TLVs.
  • the policy is inserted in the TLV and the same TLV can be used to activate policies.
  • the routing protocol message to be used is a hybrid SDN protocol message comprising a parameter indicating if the routing protocol message is an activation or deactivation protocol message.
  • the method S200 may further comprise a process S200A for receiving routing policy rules in the second router elements of communications network, e.g. a RATN.
  • a process S200A for receiving routing policy rules in the second router elements of communications network, e.g. a RATN.
  • Figure 10 is a flowchart illustrating the process S200A.
  • the process S200A in a second router element corresponds to the process S100A in the first router element.
  • Said process S200A may comprise following steps:
  • S210 - receiving one or more routing policy rules carried by a routing protocol message
  • S220 - storing the received one or more routing policy rules in a policy rule set
  • S230 - forwarding the routing protocol message comprising the one or more routing policy rules along a pre-selected routing path comprising the second router elements for which the one or more routing policy rules are to be updated.
  • the routing protocol message to be used is a modified and extended OSPF protocol message comprising a TLV parameter.
  • the automated distribution and activation of policies is achieved by using new type of TLVs.
  • the policy is inserted in the TLV and the same TLV can be used to activate policies.
  • the routing protocol message to be used is a hybrid SDN protocol message comprising a parameter indicating if the routing protocol message is carrying one or more policy rules.
  • this system is based on I2RS standard.
  • the application is associated with the first router element.
  • the RATN is configured to operate according to the I2RS standard, which states that each application should be able to communicate with each router element in the network. This communication is based on I2RS comprising an I2RS client in the first router element and an I2RS agent in each second router element.
  • the proposed solution using the I2RS interface makes it possible for the radio Operation Support System (OSS) or a Radio Access Network (RAN) node such as an evolved NodeB (eNB in LTE) or Radio Network Controller (RNC) to install and control policies in the routed network without being and active part of the routed network.
  • RAN Radio Access Network
  • eNB evolved NodeB
  • RNC Radio Network Controller
  • the I2RS interface also makes it possible for a SDN controller to install and control policies in a hybrid SDN model.
  • the hybrid SDN model leverages the benefits of the simple control of managing specific data flows (policies) as in the centralized model with the scalability and resiliency of the distributed control plane model.
  • a RAN node such as an eNB or RNC can also take active part in the routed network to install and activate policies directly via OSPF or IS-IS TLVs.
  • the technique may be implemented in digital electronically circuitry, or in computer hardware, firmware, software, or in combinations of them.
  • Apparatus of the technique may be implemented in a computer program product tangibly embodied in a machine readable storage device for execution by a programmable processor; and method steps of the technique may be performed by a programmable processor executing a program of instructions to perform functions of the technique by operating on input data and generating output.
  • the technique may advantageously be implemented in one or more computer programs that are executable on a programmable system including at least one programmable processor coupled to receive data and instructions from, and to transmit data and instructions to, a data storage system, at least one input device, and at least one output device.
  • Each computer program may be implemented in a high-level procedural or object- oriented programming language, or in assembly or machine language if desired; and in any case, the language may be a compiled or interpreted language.
  • a processor will receive instructions and data from a readonly memory and/or a random access memory.
  • Storage devices suitable for tangibly embodying computer program instructions and data include all forms of non-volatile memory, including by way of example semiconductor memory devices, such as EPROM (erasable programmable read only memory), EEPROM (electrically erasable programmable read only memory), and flash memory devices; magnetic disks such internal hard disks and removable disks; magneto-optical disks; and CD-ROM (Compact Disc Read-Only Memory) disks. Any of the foregoing may be supplemented by, or incorporated in, specially -designed ASICs (Application Specific Integrated Circuits).
  • ASICs Application Specific Integrated Circuits
  • Figure 1 1 is a block diagram illustrating a router element of a Radio Access Transport Network.
  • the first and second router elements enable routing of data packets by means of routing policy rules of routing policy sets in said router elements, wherein the routing policy rules are controlled by the first router element and by an application 20 linked to, e.g. connect to or integrated with, the first router element of a communications network, e.g. a Radio Access Transport Network.
  • a communications network e.g. a Radio Access Transport Network.
  • FIG 1 1 both alternatives are illustrated: the application 20 connected to the router element, and integrated with the router element in dashed line. A skilled person will understand that one of the alternative is present at the time.
  • the application may be a radio base station, RBS, associated, i.e. communicating with and/or linked to the first router element.
  • RBS radio base station
  • the herein above described method S100 and embodiments of the method may be implemented and provided as a computer program comprising computer program code which, when run in a processor of a system, causes the system to perform the method steps of said method and embodiments. Further, it may be provided a computer program product comprising a computer program for implementing the above described method and embodiments of the method and a computer readable means on which the computer program is stored.
  • FIG. 1 1 is a block diagram illustrating one example of a router element, preferably a first router element 30, 30', 30" in a communications network, e.g. a Radio Access Transport Network.
  • the router element comprises a router controller 410 implemented by at least one processing circuitry 410 comprising a processor unit 412 and a memory storage 414.
  • the router element 30 further comprises an interface 420 for enabling input and output communication via hop links 12 with other elements, etc.
  • the element 30, 30', 30" may also comprise computer readable means or computer readable storage medium 430 on which the computer program is stored. Said means or medium 430 may be fixed in the node or removable.
  • said may comprise a different number of computer readable means or computer readable storage medium 430, and the illustrated number of computer readable means or computer readable storage medium 430 only is for illustrative purposes.
  • One or several of the computer readable means or computer readable storage medium 430 may be physically separated from the other computer readable means or computer readable storage medium 430, or may reside on the same physical media.
  • the storage medium 430 may comprise the network topology database TDB (22 in figures 1 and 4), global policy database GPDB (24 in figures 1 and 4) and network metrics (28 in figures 1 and 4).
  • Said processing circuitry 410 causes the node to perform the steps of the above described method S100 and embodiments thereof.
  • the processing circuitry 410 of the router element 30, 30', 30" is adapted to and operative to perform:
  • the Radio Access Transport Network is time synchronized, and the activation or deactivation message comprises time information for activating or deactivating a routing policy rule of a policy rule set in one of each of said one or more router elements.
  • a synchronization signal is distributed to all router elements which supports the synchronized activation and deactivation of policy rules.
  • the activation or deactivation message is configured to activate or deactivate a routing policy rule of the policy rule set in a router element direct or essentially simultaneously upon reception of said message.
  • the activation or deactivation message is a routing protocol message.
  • Said routing protocol message may also distribute policy rules to different router elements, i.e. second router elements, from said first router element.
  • the router controller 410 of the router element being a first router element, the router controller being a processing circuitry 410 which is adapted to perform:
  • the router controller of the router element being a first router element, the router controller being a processing circuitry 410 which may further be adapted to perform:
  • the routing protocol message is an OSPF or IS-IS protocol message comprising a TLV parameter indicating if the routing protocol message is an activation or deactivation protocol message.
  • the routing protocol message is an SDN protocol message comprising a parameter indicating if the routing protocol message is an activation or deactivation protocol message.
  • Said routing protocol messages may also be used for distributing policy rules from a first router element to several second router elements.
  • the distribution of said routing protocol messages is performed from a first router element to several second router elements simultaneously, not one second router element at the time as stated in the I2RS standard.
  • the above mentioned embodiments may be implemented as processing circuitry 410 and a computer program comprising computer program code which, when run in a processor circuitry of a router element, causes the element to perform the method steps of the method S100B:
  • S150 - receiving a decision from the application to activate or deactivate a routing policy rule stored in the routing policy set of one or more second router elements;
  • S160 - selecting at least one routing path comprising the second router elements for which the routing policy rule is to be activated or deactivated;
  • S170 - sending one activation or deactivation message along the selected routing path comprising the second router elements for which the routing policy rule of the policy rule set is to be activated or deactivated;
  • the method S100 may further comprise the process S100A for distributing routing policy rules to the router elements of the RATN.
  • Said process may comprise following steps:
  • S120 - retrieving actual router element routing state information for the second router elements from a topology database of the Radio Access Transport Network;
  • S130 - selecting based on the actual router element routing state information at least one routing path comprising the second router elements for which policy rule sets are to be updated with the one or more routing policy rules;
  • S140 - sending the one or more routing policy rules in a routing protocol message along a selected routing path comprising the second router elements for which the one or more routing policy rules are to be updated.
  • Figure 12 is a block diagram illustrating another example of a router element, preferably a first router element, in a Radio Access Transport Network.
  • the above mentioned embodiments of the method S100 may be implemented as modules of a router element 30, 30', 30" to perform the method steps of the process S100B of the method S100.
  • Different storages may be connected to the router element 30, 30', 30".
  • Said storages may comprise the network topology database TDB (22 in figures 1 and 4), global policy database GPDB (24 in figures 1 and 4) and network metrics (28 in figures 1 and 4).
  • the router element 30, 30', 30" may therefore comprise a first module
  • a routing policy rule 510 for receiving a decision from the application (not shown; see figure 2 or 3) to activate or deactivate a routing policy rule stored in the routing policy set of one or more second router elements, a second module 520 for selecting at least one routing path comprising the second router elements for which the routing policy rule is to be activated or deactivated, a third module 530 for sending one activation or deactivation message along the selected routing path comprising the second router elements for which the routing policy rule of the policy rule set is to be activated or deactivated, and a forth module 540 for routing and sending data packets handled by the application according to the updated policy rule set.
  • the router element 30, 30', 30" may therefore comprise a fifth module 550 for receiving one or more routing policy rules from the application, a sixth module 560 for retrieving actual router element routing state information for the second router elements from a topology database of the Radio Access Transport Network, a seventh module 570 for selecting based on the actual router element routing state information at least one routing path comprising the second router elements for which policy rule sets are to be updated with the one or more routing policy rules, and an eight module 580 for sending the one or more routing policy rules in a routing protocol message along a selected routing path comprising the second router elements for which the one or more routing policy rules are to be updated.
  • the above mentioned embodiments of the method S100 may be implemented as modules of a router element 30, 30', 30" to perform the method steps of the process S100A of the method S100.
  • a router element 30, 30', 30" may comprise further modules for implementing the different embodiments of the method S100, said modules causes the node to perform the different embodiments of the method S100.
  • the computer program comprises computer program code which, when run in a processor circuitry of a node, causes the node to perform the different embodiments of the method S100.
  • a carrier containing the computer program wherein the carrier is one of an electronic signal, optical signal, radio signal or computer readable storage medium.
  • Figure 13 is a block diagram illustrating a router arrangement of a Radio
  • the router arrangement is adapted to enable routing of data packets by a second router element of a Radio Access Transport Network by means of routing policy rules of a policy rule set.
  • Said Radio Access Transport Network comprises at least one first router element for distributing routing policy rules via selected routing paths comprising the router elements for which the routing policy rule set is to be updated.
  • a router arrangement 40, 40', 40" comprises at least one processing circuitry 610 comprising a processor unit 612 and a memory storage 614.
  • the router arrangement 40, 40', 40" further comprises an interface 620 for enabling input and output communication via hope links with other nodes and units, etc.
  • the router arrangement 40, 40', 40" may also comprise computer readable means or computer readable storage medium 630 on which the computer program is stored. Said means or medium 630 may be fixed in the node or removable.
  • said may comprise a different number of computer readable means or computer readable storage medium 630, and the illustrated number of computer readable means or computer readable storage medium 630 only is for illustrative purposes.
  • One or several of the computer readable means or computer readable storage medium 630 may be physically separated from the other computer readable means or computer readable storage medium 630, or may reside on the same physical media.
  • the computer readable means or computer readable storage medium 630 may comprise the local policy data base, LPDB (26 in figures 1 and 4).
  • Said processing circuitry 610 causes the node to perform the steps of the above described method S200 and embodiments thereof.
  • the router arrangement 40, 40', 40" comprises a router controller
  • processing circuitry 610 implemented as a processing circuitry 610 being adapted to and operative to perform:
  • the router controller i.e. a processing circuitry 610, may further be adapted to perform:
  • routing protocol message comprising the one or more routing policy rules along a pre-selected routing path comprising the second router elements for which the one or more routing policy rules are to be updated.
  • the Radio Access Transport Network is time synchronized, and the activation or deactivation message comprises time information for activating or deactivating a routing policy rule of a policy rule set in one of each of said one or more router elements.
  • the activation or deactivation message is configured to activate or deactivate a routing policy rule of the policy rule set in a router arrangement 40 direct or essentially simultaneously upon reception of said message.
  • the activation or deactivation message is preferably a routing protocol message. Different alternative of routing protocol messages are possible, if said protocol is adapted to distribute policy rules, activation messages and deactivation messages.
  • the router arrangement may be adapted to receive and handle an adapted OSPF or IS-IS protocol messages comprising a TLV parameter indicating if the routing protocol message is an activation or deactivation protocol message, and/or comprising one or more routing policy rules.
  • the router arrangement may be adapted to handle an adapted SDN protocol message comprising a parameter indicating if the routing protocol message is an activation or deactivation protocol message, and/or comprises one or more routing policy rule.
  • processing circuitry 610 and a computer program comprising computer program code which, when run in a processor circuitry of a node, causes the router arrangement 40, 40', 40" to perform the method steps of the method S200B:
  • S240 - receiving one activation or deactivation message for activating or deactivating one or more routing policy rules of the policy rule set;
  • S250 - activating or deactivating one or more routing policy rules of the policy rule set;
  • S210 - receiving one or more routing policy rules carried by a routing protocol message
  • S220 - storing the received one or more routing policy rules in the policy rule set
  • the computer program comprises computer program code which, when run in a processor circuitry of a node, causes the node to perform the different embodiments of the method S200.
  • a carrier containing the computer program wherein the carrier is one of an electronic signal, optical signal, radio signal or computer readable storage medium.
  • Figure 14 is a block diagram illustrating another example of a router arrangement 40, 40', 40" of a second router element.
  • the above mentioned embodiments of the method S200 may be implemented as modules of a router arrangement 40, said modules causes the second router element to perform the method steps of the method S200 and its embodiments.
  • a computer readable means or computer readable storage medium may comprise the local policy data base, LPDB, (26 in figures 1 and 4).
  • the router arrangement 40, 40', 40" may therefore comprise a first module 710 for receiving one activation or deactivation message for activating or deactivating one or more routing policy rules of the policy rule set, a second module 720 for activating or deactivating one or more routing policy rules of the policy rule set, and a third module 730 for routing and sending data packets according to the updated policy rule set.
  • the router arrangement 40, 40', 40" may comprise further modules to be able to perform process S200A: a fourth module 740 for receiving one or more routing policy rules carried by a routing protocol message, a fifth module 750 for storing the received one or more routing policy rules in the policy rule set, and a sixth module 760 for forwarding the routing protocol message comprising the one or more routing policy rules along a pre-selected routing path comprising the second router elements for which the one or more routing policy rules are to be updated.
  • a router arrangement 40, 40', 40" may comprise further modules for implementing the different embodiments of the method S200, said modules causes the router element to perform the different embodiments of the method S200.
  • One or several of the data storage areas may be physically separated from the other data storage areas, or may reside on the same physical media.
  • FIG. 15 is a block diagram illustrating a network comprising router elements R1 , R2, R3, R4, and R5.
  • router element R1 talks to router element R2 and that the normal path chosen by the routing protocol message is the direct connection between the two (as indicated by the arrow to the left).
  • the normal path chosen by the routing protocol message is the direct connection between the two (as indicated by the arrow to the left).
  • R1 -R3-R4-R5-R2 This is achieved by inserting a policy into R1 that say that for traffic X, send the packets to R3.
  • R3, that is still using ordinary routing is adapted to rout traffic the shortest path.
  • the shortest path from R3 to R2 goes through R1 and consequently sends the packet back to R1 .
  • the policy in R1 is matched again and the packet is sent to R3 and so on, which results is a routing loop.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Data Exchanges In Wide-Area Networks (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

La présente invention concerne des procédés et des éléments de routeur pour permettre le routage de paquets de données, le routage étant géré par une application reliée à un premier élément de routeur d'un réseau de transport d'accès radio (RATN) et au moyen de règles de politique de routage d'ensembles de politiques de routage dans des seconds éléments de routeur du RATN. La présente invention concerne également des procédés pour distribuer des règles de politique de routage dans le RATN, et des procédés pour l'activation ou la désactivation des règles de politique de routage dans lesdits seconds éléments de routeur.
PCT/SE2014/051555 2014-12-19 2014-12-19 Activation et distribution de règles de politique dans un réseau de communication WO2016099368A1 (fr)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1026867A2 (fr) * 1998-12-22 2000-08-09 Nortel Networks Corporation Système et procédé de support de politiques configurables pour des services d'annuaires en réseau
US20130223221A1 (en) * 2012-02-27 2013-08-29 Verizon Patent And Licensing Inc. Traffic Policing For MPLS-Based Network
US8724626B1 (en) * 2013-10-07 2014-05-13 tw telecom holdings inc. Redirecting network traffic based on content

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1026867A2 (fr) * 1998-12-22 2000-08-09 Nortel Networks Corporation Système et procédé de support de politiques configurables pour des services d'annuaires en réseau
US20130223221A1 (en) * 2012-02-27 2013-08-29 Verizon Patent And Licensing Inc. Traffic Policing For MPLS-Based Network
US8724626B1 (en) * 2013-10-07 2014-05-13 tw telecom holdings inc. Redirecting network traffic based on content

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