# Patent

## Title
Methods, systems, and computer readable media for providing policy and charging rules function (PCRF) with integrated openflow controller

## Abstract

The subject matter described herein includes methods, systems, and computer readable media for providing a PCRF with an integrated openflow controller. According to one system, a policy and charging rules function (PCRF) is configured to determine policies to apply to network sessions or users. An openflow controller is integrated with the PCRF and configured to provide instructions to telecommunications network elements in an openflow protocol to implement the policies.

## Background
PRIORITY CLAIM
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/659,967 filed Jun. 14, 2012; the disclosure of which is incorporated herein by reference in its entirety.


TECHNICAL FIELD
The subject matter described herein relates to enabling flexible allocation of resources in telecommunications networks. More particularly, the subject matter described herein relates to a PCRF with an integrated openflow controller.
BACKGROUND
In telecommunications networks, global Internet protocol traffic is increasing at a rate of forty to fifty percent per year. In order to retain subscribers, it is desirable for service providers to keep monthly charges to subscribers relatively unchanged. Keeping charges constant with increasing traffic requires a reduction in expenses. For example, with a forty percent increase in traffic, service providers must reduce capital expenses and operational expenses by forty to fifty percent per gigabyte per second per year to achieve relatively constant pricing.
One possible method for reducing capital and operational expenses is to use software defined networks (SDNs). SDNs can be used to manage flows, control switches, control network access, and track user location and motion. SDNs can also be used to efficiently use network components. For example, SDNs may be used to power off unused equipment during non-peak periods to conserve energy.
Some SDN models centralize the control of network elements, such as routers and switches, by removing intelligence from the routers and switches and placing that intelligence in a centralized location. One such effort to provide centralized control of routers and switches is the openflow architecture described in the Openflow Switch Specification, Version 1.1.0, Feb. 28, 2011, the disclosure of which is incorporated herein by reference in its entirety and a copy of which is attached hereto. According to the Openflow Switch Specification, an openflow controller controls functions of openflow-enabled switches. Openflow has not been used to control telecommunications network elements. Accordingly, there exists a need for extending openflow into telecommunications networks to reduce operating and capital expenses and to make networks more scalable and more flexible.
SUMMARY
The subject matter described herein includes methods, systems, and computer readable media for providing a PCRF with an integrated openflow controller. According to one system, a policy and charging rules function (PCRF) is configured to determine policies to apply to network sessions or users. An openflow controller is integrated with the PCRF and configured to provide instructions to telecommunications network elements in an openflow protocol to implement the policies.
The subject matter described herein can be implemented in software in combination with hardware and/or firmware. For example, the subject matter described herein may be implemented in software executed by one or more processors. In one exemplary implementation, the subject matter described herein may be implemented using a non-transitory computer readable medium having stored thereon computer executable instructions that when executed by the processor of a computer control the computer to perform steps. Exemplary computer readable media suitable for implementing the subject matter described herein include disk memory devices, chip memory devices, programmable logic devices, and application specific integrated circuits. In addition, a computer readable medium that implements the subject matter described herein may be located on a single device or computing platform or may be distributed across multiple devices or computing platforms.



BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the subject matter described herein will now be explained with reference to the accompanying drawings, of which:
FIG. 1 is a network diagram illustrating a PCRF with an integrated openflow controller controlling telecommunications network elements according to an embodiment of the subject matter described herein;
FIG. 2 is a block diagram illustrating an exemplary architecture for an SDN including an openflow-enabled PCRF according to an embodiment of the subject matter described herein; and
FIG. 3 is a message flow diagram illustrating exemplary messaging for a PCRF to provide policy instructions to telecommunications network nodes via using an openflow protocol according to an embodiment of the subject matter described herein.



DETAILED DESCRIPTION
The subject matter described herein includes a PCRF with an integrated openflow controller. FIG. 1 illustrates an example of such a PCRF. In FIG. 1 PCRF 100 includes integrated openflow controller 102. Openflow controller 102 implements the above-described openflow protocol to control one or more of eNode B 104, BRAS/BNG 106, GGSN or PDN-GW/S-GW 108, a Wi-Fi access point (not shown) or one or more openflow switches or routers (not shown). In the illustrated example, PCRF 100 also includes a non-openflow interface 109 for controlling non-openflow devices, such as online charging system (OCS) 110 or deep packet inspection (DPI) node 112. Non-openflow interface 109 may be a Diameter interface or other suitable interface for communicating with non-openflow nodes, such as OCS 110 and DPI 112.
Conventionally, the network in FIG. 1 operated by providing much of the routing intelligence in nodes 104, 106, and 108. PCRF 100 conventionally controlled such nodes using only a layer 7 protocol, such as Diameter. In the illustrated embodiment, PCRF 100 may include at least some of the same routing intelligence conventionally contained in nodes 104, 106, and 108 and use openflow controller 102 to control switching and routing performed by nodes 104, 106, and 108. Thus, PCRF 100 may control nodes using the openflow protocol in addition to or instead of a layer 7 protocol, such as Diameter.
FIG. 2 is a block diagram illustrating an exemplary architecture for a software-defined network including PCRF 100 with integrated openflow controller 102. Referring to FIG. 2, PCRF 100 controls BRAS/BNG 106, GGSN 108A, PDN-GW/S-GW 108B, eNode B 104, Wi-Fi access point 114 and openflow switches/routers 116 using openflow. PCRF 100 may also communicate with DSR 118 and HSS 120 using any suitable protocol, such as Diameter. PCRF 100 may support various applications, such as content streaming 122, voice over LTE 124, rich communications suite (RCS) 126, cloud services 128, and business applications 130.
FIG. 3 is a flow diagram illustrating exemplary messages that may be exchanges exchanged when a node such as BRAS/BNG 106 is controlled by PCRF 100 using openflow. Referring to FIG. 3, in line 1, a user element 300 sends an initial Ethernet frame or an IP packet to the network. BRAS/BNG 106 receives the frame or packet, performs a lookup in its flow table, and determines that there are no matching entries. Accordingly, in line 2, BRAS/BNG 106 sends the frame or packet to PCRF 100 to determine what policy to apply to the frame or packet and to subsequent frames or packets in the same flow as the Ethernet frame or IP packet. Openflow controller 102 receives the frame or packet and determines the policy to apply to the frame or packet. In line 3, openflow controller 102 sends an openflow add command instructing BRAS/BNG 106 to add an entry to its flow table to implement a policy for frames associated with the same flow as the received Ethernet frame. Subsequent Ethernet frames or IP packets associated with the same flow may be switched by BRAS/BNG 106 using the entry added to its flow table by openflow controller 102.
It will be understood that various details of the presently disclosed subject matter may be changed without departing from the scope of the presently disclosed subject matter. Furthermore, the foregoing description is for the purpose of illustration only, and not for the purpose of limitation.

## Claims

1. A system for providing a policy controlling network, the system comprising:
a policy and charging rules function (PCRF) configured to determine policies to apply to network sessions or users, wherein the PCRF is configured to receive, from a broadband remote access server/broadband network gateway (BRAS/BNG), an initial frame or packet to determine what policy to apply to subsequent frames or packets associated with the same flow as the initial frame or packet; and
an openflow controller integrated with the PCRF and configured to provide instructions to telecommunications network elements in an openflow protocol to implement the policies, wherein the PCRF with the integrated openflow controller comprises an openflow-enabled PCRF that controls nodes using the openflow protocol, wherein the openflow controller receives the initial frame or packet, determines the policy to apply to the subsequent frames or packets and sends an openflow command to the BRAS/BNG to add an entry to a flow table of the BRAS/BNG to implement the policy for the subsequent frames or packets associated with the same flow as the initial frame or packet.

2. The system of claim 1 wherein the openflow controller is configured to provide instructions in the openflow protocol to one or more of the BRAS/BNG, a gateway GPRS support node (GGSN), a packet data network gateway/server gateway (PDN-GWIS-GW), an evolved node B (eNode B).

3. The system of claim 1 wherein the openflow controller is configured to provide instructions in the openflow protocol to one or more of a Wi-Fi access point, a switch, and a router.

4. The system of claim 1 wherein the PCRF includes a non-openflow interface for providing instructions to at least some of the telecommunications network elements using a non-openflow protocol.

5. The system of claim 4 wherein the non-openflow protocol comprises a Diameter protocol.

6. The system of claim 1 wherein the PCRF is configured to communicate with a home subscriber server (HSS) using Diameter.

7. The system of claim 1 wherein the PCRF is configured to communicate with a Diameter signaling router (DSR) using Diameter.

8. The system of claim 1 wherein the PCRF includes a non-openflow interface for controlling non-openflow devices.

9. The system of claim 8 wherein the non-openflow devices include an online charging system (OCS).

10. The system of claim 8 wherein the non-openflow devices include a deep packet inspection (DPI) node.