Abstract:
The present disclosure discloses a method and system for achieving enhanced performance for application message handling. The disclosed system includes a device and is configured to receive, at a first processing layer implemented by the device, a message addressed to a first port. The system is further configured to modify the message to be addressed to a second port indicated in a body of the message prior to forwarding the message to a second processing layer implemented by the device. Furthermore, the system is configured to forward, by the first processing layer to the second processing layer, the modified message addressed to the second port.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims the benefit of priority on U.S. Provisional Patent Application 61/732,829, filed Dec. 3, 2012, the entire contents of which are incorporated by reference. 
         [0002]    Related patent applications to the subject application include the following: (1) U.S. Patent Application entitled System and Method for Achieving Enhanced Performance with Multiple Networking Central Processing Unit (CPU) Cores by Janakiraman, et al., U.S. application Ser. No. 13/692,622, filed Dec. 3, 2012, attorney docket reference no. 6259P186; (2) U.S. Patent Application entitled Ingress Traffic Classification and Prioritization with Dynamic Load Balancing by Janakiraman, et al., U.S. application Ser. No. 13/692,608, filed Dec. 3, 2012, attorney docket reference no. 6259P191; (3) U.S. Patent Application entitled Method and System for Maintaining Derived Data Sets by Gopalasetty, et al., U.S. application Ser. No. 13/692,920, filed Dec. 3, 2012, attorney docket reference no. 6259P192; (4) U.S. Patent Application entitled Session-Based Forwarding by Janakiraman, et al., U.S. Application No. ______, filed Jun. 14, 2013, attorney docket reference no. 6259P184; (5) U.S. Patent Application entitled Rate Limiting Mechanism Based on Device Load/Capacity or Traffic Content by Nambiar, et al., U.S. Application No. ______, filed Jun. 14, 2013, attorney docket reference no. 6259P185; (6) U.S. Patent Application entitled Control Plane Protection for Various Tables Using Storm Prevention Entries by Janakiraman, et al., U.S. Application No. ______, filed Jun. 14, 2013, attorney docket reference no.  6259P188.    
     
    
     FIELD 
       [0003]    The present disclosure relates to networking processing performance. In particular, the present disclosure relates to a system and method for achieving enhanced performance for application message handling in a network device. 
       BACKGROUND 
       [0004]    Network devices, such as network controllers, access points, network servers, etc. exchange network packets. The network packets may be generated by applications run on a network device, and communicated to another network device for the purpose of processing of those network packages. For example, an application run by an access point may generate network packets that include application specific data. The access point then transmits the network packets to a network controller to enable an application run by the network controller to process the application specific data. Such applications may include security applications, network performance applications, data routing applications, etc. 
         [0005]    Because there are typically numerous network packets being transferred between network devices over a computing network simultaneously, the efficient handling of those network packets becomes increasingly important in order to avoid data bottlenecks at the destination network devices, as well as to enable the timely processing and exchange of application-specific data between applications on different network devices. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    The present disclosure may be best understood by referring to the following description and accompanying drawings that are used to illustrate embodiments of the present disclosure. 
           [0007]      FIG. 1  is a block diagram of exemplary system architecture of a computing network. 
           [0008]      FIG. 2  illustrates exemplary architecture at multiple processing planes according to embodiments of the present disclosure. 
           [0009]      FIG. 3A  is a diagram illustrating an exemplary application message network packet according to embodiments of the present disclosure. 
           [0010]      FIG. 3B  is a diagram illustrating an exemplary translated application message network packet according to embodiments of the present disclosure. 
           [0011]      FIG. 4  is a flow diagram of a method for translating a network packet according to embodiments of the present disclosure. 
           [0012]      FIG. 5  is a block diagram illustrating a system of according to embodiments of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    In the following description, several specific details are presented to provide a thorough understanding. While the context of the disclosure is directed to performance enhancements for message handling in a network device, one skilled in the relevant art will recognize, however, that the concepts and techniques disclosed herein can be practiced without one or more of the specific details, or in combination with other components, etc. In other instances, well-known implementations or operations are not shown or described in details to avoid obscuring aspects of various examples disclosed herein. It should be understood that this disclosure covers all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure. 
         [0014]    Embodiments of the present disclosure relate to enhancing message handling performance in a network device. In particular, the present disclosure relates to a system and method for achieving enhanced message handling performance by translation of one or more addressing fields of an application network data packet in a first processing layer of the network device prior to forwarding of the application network packet to a second processing layer of the network device. The first processing layer may be a datapath, a networking operating system, or a secondary operating system executing on the device, and the second processing layer may be a control plane, a UNIX™ based operating system such as LINUX™, a real-time operating system, or a primary operating system executing on the device. In the embodiments discussed herein, the network device may be a network controller that receives a message (e.g., the network data packet), the first processing layer may be the datapath, and the second processing layer may be a control plane . However, the techniques discussed herein need not be limited to a network controller executing a datapath processing layer and a control plane processing layer, as any network device, such as an access point, a network switch, a network router, a network server, a network controller, etc. may employ any combination of processing layers in accordance with the discussion herein. However, in order to avoid obscuring the invention, the remaining description will describe, but should not be limited to, a network controller with a datapath processing layer and a control plane processing layer. 
         [0015]    Applications run on different network devices communicate with one another via the exchange of messages, such as network routable data packets addressed to devices and/or applications executing on destination devices. As discussed herein, references to messages, data packets, and network packets are interchangeable. For example, an application run by an access point may generate application data. The application provides the application data to a message handler at the access point, which encapsulates the application data in a network packet suitable for transmission over a computing network. In one embodiment, the network packet is a user datagram protocol (UDP) network packet that is divided into a plurality of different fields. The different fields include an Ethernet header field, an internet protocol (IP) address header field, a UDP header field, a message passing protocol header field, and a message payload. The message handler at the access point then transmits the message over the computing network to a destination device, such as a network controller. 
         [0016]    Network controllers receive the messages including the network packets in a datapath of the network controller, and then provide the network packets to a control plane of the network controller. A message handler operating in the control plane of the network controller receives the network packet on a UDP socket, and then delivers the network packet by reading the network packet, writing data to the network packet to enable a recipient application identify the data packet, and forwarding the network packet to the destination application on an operating system socket (e.g., a UNIX kernel socket). Then, the application on the network controller reads the network packet from the operating system socket and processes the application-specific data in the network packet. 
         [0017]    In one embodiment, the approach of utilizing a message handler in the control plane of a network device, such as a network controller, is removed. In one embodiment, as discussed in greater detail below, processes running in the datapath (i.e., first processing layer) of the network controller translate one or more addressing fields of the network packet. After translating the network packet addressing fields in the datapath, a destination application operating in the control plane (i.e., second processing layer) monitors network packets on an operating system socket for packets addressed to the specific recipient application. When a network packet addressed to the application is detected by the application, the network packet may then simply be read and processed by the application. As a result, the consumption of processing resources consumed by the reading and writing of data to the network packets by a message handler in the control plane are avoided, which frees computing resources in the control plane for other purposes. Furthermore, bottlenecks caused by network packets being funneled into a message handler in the control plane are also avoided. 
         [0018]      FIG. 1  is a block diagram of exemplary system architecture of a computing network  100  in which the embodiment discussed herein may be deployed. System architecture illustrates a network  100  that includes a plurality of network devices, such as controller  106 , router  102 , network switch  104 , wireless access point (AP)  108 , and network management server  110 . Although only a single controller, router, network switch, wireless AP, and network management server are illustrated, the network  100  illustrated by system architecture may include one or more of each of the different network devices consistent with the discussion herein. In one embodiment, the controller  106  supports devices such as router  102 , network switch  104 , wireless AP  108  to enable communication channels within the network  100  that allow sharing of resources and information. In one embodiment, controller  106  provides networking across wireless and wired network connections, VPN connections, and remote services, and integrates networking and security functions into the network infrastructure and user experience. 
         [0019]    The network  100 , as referred to and discussed herein, may run on one Local Area Network (LAN) and may be incorporated into the same physical or logical system, or different physical or logical systems. Alternatively, network  100  may reside on different LANs, wide area networks, etc. that may be coupled together via the Internet but separated by firewalls, routers, and/or other network devices. It should be noted that various other network configurations can be used including, for example, hosted configurations, distributed configurations, centralized configurations, etc. 
         [0020]    The system architecture further includes one or more client computing devices  120 - 1  through  120 -N coupled to the network  100  via network switch  104 , and one or more client computing devices  125 - 1  through  125 -N coupled to the network  100  via wireless AP  108 . Client computing devices  120  connect to the network switch  104 , and client computing devices  125  connect to the wireless AP  108 , to access services such as the Internet through controller  106 . 
         [0021]    The system architecture further includes one or more network management servers, such as network management server  110 , coupled to the network  100 . In one embodiment, network management server  110  executes network management applications. For example, network management server  110  may provide manual or automated network management services to manage various aspects affecting the network, such as managing the radio frequency environment, controllers, wired infrastructure, and access points. Network management server  110  may further provide a user interface to network administrators to provide charts, tables, diagnostic information and alerts. 
         [0022]    In one embodiment, controller  106 , router  102 , network switch  104 , wireless AP  108 , and network management server  110  are purpose-made digital devices, each containing a processor, memory hierarchy, and input-output interfaces. In one embodiment of the invention, a MIPS-class processor such as those from Cavium or RMI is used. Other suitable processors, such as those from Intel or AMD may also be used. The memory hierarchy traditionally comprises fast read/write memory for holding processor data and instructions while operating, and nonvolatile memory such as EEPROM and/or Flash for storing files and system startup information. Wired interfaces are typically IEEE 802.3 Ethernet interfaces, used for wired connections to other network devices such as switches, or to a controller. Wireless interfaces may be WiMAX, 3G, 4G, and/or IEEE 802.11 wireless interfaces. In one embodiment of the invention, controllers, switches, and wireless APs operate under control of a LINUX® operating system, with purpose-built programs providing controller and access point functionality. 
         [0023]    Client computing devices  120  and  125  also contain a processor, memory hierarchy, and a number of interfaces including a wired and/or wireless interfaces for communicating with network switch  104  or wireless AP  108 . Typical client computing devices include personal computers, handheld and tablet computers, Wi-Fi phones, wireless barcode scanners, and the like. 
         [0024]      FIG. 2  illustrates a general architecture of a network device, such as controller  106 , which includes multiple processing planes according to embodiments of the present disclosure. Specifically,  FIG. 2  illustrates a controller  200  that includes at least a control plane process  210 , two or more datapath processors  220 , a network interface  250 , and one more applications, such as application 1  260  to application J  262 .  FIG. 2  further illustrates an access point  270  that includes at least a network interface  278 , a message handler  276 , and one or more applications, such as application 1  272  to application K  274 . In one embodiment, the controller  200  and the access point  270  are communicatively coupled via a computing network (not shown). Furthermore, there may be more than one access point connected to controller  200 , as well as other controllers connected to controller  200 . 
         [0025]    In controller  200 , control plane process  210  may be running on one or more CPUs or CPU cores, such as CP CPU 1  212 , CP CPU 2  214 , . . . CP CPU M  218 . Furthermore, control plane process  210  typically handles applications that perform network control or management of traffic generated by and/or terminated at network devices as opposed to data traffic generated and/or terminated at client devices. In one embodiment, the control plane process  210  executes application 1  260  to application J  262 . 
         [0026]    According to embodiments of the present disclosure, datapath processors  220  include a single slowpath (SP) processor (e.g., SP CPU  230 ) and multiple fastpath (FP) processors (e.g., FP CPU 1  240 , FP CPU 2  242 , . . . FP CPU N  248 ). Only FP processors are able to receive data packets directly from network interface  250 . SP processor, on the other hand, only receives data packets from FP processors. Also, control plane process  210  is communicatively coupled to slowpath (SP) CPU  230 , but not fastpath (FP) processors (e.g., FP CPU 1  240 , FP CPU 2  242 , . . . FP CPU N  248 ). Thus, whenever control plane process  210  needs information from datapath processors  220 , control plane process  210  will communicate with SP processor (e.g., SP CPU  230 ). 
         [0027]    In one embodiment, an application executed at access point  270  is in communication with an application executed at controller  200 . The communication is in the form of the exchange of network packets that contain application-specific data generated by corresponding applications. For example, application K  274  of access point  270  may generate data for receipt by application J  262  of controller  200 . Application K  274  provides the application-specific data to message handler  276  which encapsulates the data in a network packet suitable for transmission to controller  200 . 
         [0028]      FIG. 3A  illustrates one embodiment of a network packet  300 . The network packet is generated by an application and includes at least header fields  310 , UDP addressing data field  320 , a message passing protocol addressing data field  330 , and a message payload  340 . The header fields  310  contain standard fields, such as fields for an Ethernet header, an IP header, as well as other standard messaging fields (not illustrated). The UDP addressing data field  320  contains UDP source and UDP destination port addresses that enable the network packet  300  to be routed between appropriate devices as specified by the UDP source port and the UDP destination port addresses. The message passing protocol addressing data field  330  contains a message passing protocol source port addresses and a message passing protocol destination port address to enable the message payload within the network packet  300  to be provided to the intended destination application. In the illustration of  FIG. 3A , the controller  200  addressing is specified as port 8211, the application of access point  270  is identified by source port 8224, and the destination application of controller  200  is identified by destination port 8222. The port addresses are illustrative, as other port addresses could be utilized. In one embodiment, a data packet as illustrated in  FIG. 3A  is transmitted from network interface  278  of access point  270  over a computing network to network interface  250  of controller  200 . 
         [0029]    In one embodiment, the received network packet is processed by at least one of FP processors. In one embodiment, the FP processors perform a process, which is discussed in greater detail below in  FIG. 4 , to translate addressing fields of the received network packet. In one embodiment, the message passing protocol port address in field  380 , which identifies the port of the intended recipient application, replaces the UDP destination port address in field  370 . The remaining header fields  360  and message payload  390 , remain unchanged, except for the updated computation of a message checksum, which may be contained in the UDP addressing field  370 . 
         [0030]    As illustrated by the network packet of  FIG. 3B , the UDP destination port address  370  is updated to port 8222. In one embodiment, the translated network packet, as illustrated in  FIG. 3B , is provided to a kernel (not shown) that bridges the datapath processors  220  and the control plane process  210 . The applications (e.g., application 1  260  to application J  262 ) listen to the kernel for network packets with corresponding port addresses in the UDP destination port address. When an application detects a network packet with the appropriate addressing data, the application reads the network packet and consumes the application-specific data in message payload  390 . 
         [0031]    Because the applications of controller  200  listen for their corresponding port addresses, a message handler application need not be run in the control plane for managing the routing of network packets to appropriate applications. As a result, processing resources are freed on the control plane for applications  260  through  262 , as well as other processes on the control plane. Furthermore, when an application on controller  200  transmits application data to an application on access point  270 , the FP processors in the datapath  220  perform a complementary network packet translation process that changes the source UDP port address to the destination UDP port address. In one embodiment, the source UDP port address is translated to the destination UDP port address so that both the source and destination UDP ports are addressed to the destination device message handler port, such as port 8211. 
         [0032]      FIG. 4  is a flow diagram of a method for translating a network packet according to embodiments of the present disclosure. The method  400  is performed by processing logic that may comprise hardware (circuitry, dedicated logic, etc.), software (such as is run on a general purpose computer system, networking device, or other dedicated machine), firmware, or a combination. In one embodiment, the method  400  is performed by one or more datapath processors  220  of a network controller  200 . However, other network devices may perform the network packet translation in accordance with the techniques described herein. 
         [0033]    In one embodiment, the process begins when a FP processor in a datapath of a network controller receives a message from an application (processing block  402 ). In one embodiment, the message is a UDP network packet. In one embodiment, processing logic receives the UDP network packet on a UDP socket, such as port 8211 or port 8209. The application may be an application on a different network device, such as an access point, network server, bridge, router, etc. which has communicated the network packet to the network controller. As discussed above, the network packet may encapsulate application-specific data within the UDP network packet to be processes by a recipient application. 
         [0034]    Processing logic translates the UDP destination port address field in the message to a destination port address located in a message passing protocol destination address field of the network packet (processing block  404 ). In one embodiment, processing logic utilizes the destination application port address to overwrite the UDP port address field value in a network packet. 
         [0035]    Processing logic then provides the translated message to a control plane of the network controller (processing block  406 ). In one embodiment, processing logic forwards a translated network packet to an operating system socket specified by the message passing protocol destination address field. By providing the network packet to the socket, the recipient application can detect when a network packet is available by monitoring the UDP destination port addresses. The intended destination application of the controller may then consume the application-specific data in the payload of the network packet. 
         [0036]    In one embodiment, the process performed at processing block  406  may also include encapsulating the network packet into a transmission control protocol (TCP) session within the dataplane. Furthermore, in one embodiment, processing logic can further convert the network packet to one or more UDP packets. In this embodiment, the message passing protocol header data (i.e., the destination port address) is encapsulated into a TCP session identifier that can be utilized for tunneling the network packet(s) to the intended recipient application. In this embodiment, the network packet(s) would be further modified by adding internet protocol (IP) header data to the network packet(s) for the corresponding TCP session. Because the datapath manages the TCP session creation and packet transfer, a recipient application monitors for the converted UDP packets. 
         [0037]      FIG. 5  is a block diagram illustrating a network device according to embodiments of the present disclosure. Network device  500  includes at least a network interface  510  capable of communicating to a wired or wireless network, a memory  520  capable of storing data, a slowpath processor core  530  capable of processing network data packets, and one or more fastpath processor cores, including fastpath processor core  542 , fastpath processor core  544 , . . . , fastpath processor core  548 , which are capable of processing network data packets. Moreover, network device  500  may be used as a network switch, network router, network controller, network server, etc. Further network device  500  may serve as a node in a distributed or a cloud computing environment. 
         [0038]    Network interface  510  can be any communication interface, which includes but is not limited to, a modem, token ring interface, Ethernet interface, wireless IEEE 802.11 interface (e.g., IEEE 802.11n, IEEE 802.11ac, etc.), cellular wireless interface, satellite transmission interface, or any other interface for coupling network devices. In some embodiments, network interface  510  may be software-defined and programmable, for example, via an Application Programming Interface (API), and thus allowing for remote control of the network device  600 . 
         [0039]    Memory  520  can include storage components, such as, Dynamic Random Access Memory (DRAM), Static Random Access Memory (SRAM), etc. In some embodiments, memory  520  is a flat structure that is shared by all datapath processors (including, e.g., slow path processor core  530 , fastpath processor core  542 , fastpath processor core  544 , . . . , fastpath processor core  548 , etc.), and not tied to any particular CPU or CPU cores. Any datapath processor can read any memory location within memory  520 . Memory  520  can be used to store various tables to assist software network packet forwarding. For example, the tables may include, but are not limited to, a bridge table, a session table, a user table, a station table, a tunnel table, a route table and/or route cache, etc. . 
         [0040]    Slowpath processor core  530  typically includes a networking processor core that is capable of processing network data traffic. Slowpath processor core  530  is a single dedicated CPU core that typically handles table managements. Note that, slowpath processor core  530  only receives data packets from one or more fastpath processor cores, such as fastpath processor core  542 , fastpath processor core  544 , . . . , fastpath processor core  548 . In other words, slowpath processor core  530  does not receive data packets directly from any line cards or network interfaces. 
         [0041]    Fastpath processor cores  542 - 548  also include networking processor cores that are capable of processing network data traffic. However, by definition, fastpath processor cores  542 - 548  only performs “fast” packet processing. Thus, fastpath processor cores  542 - 549  do not block themselves and wait for other components or modules during the processing of network packets. Any packets requiring special handling or wait by a processor core will be handed over by fastpath processor cores  542 - 548  to slowpath processor core  530 . 
         [0042]    According to embodiments of the present disclosure, network services provided by network device  500 , solely or in combination with other wireless network devices, include, but are not limited to, an Institute of Electrical and Electronics Engineers (IEEE) 802.1x authentication to an internal and/or external Remote Authentication Dial-In User Service (RADIUS) server; an MAC authentication to an internal and/or external RADIUS server; a built-in Dynamic Host Configuration Protocol (DHCP) service to assign wireless client devices IP addresses; an internal secured management interface; Layer-3 forwarding; Network Address Translation (NAT) service between the wireless network and a wired network coupled to the network device; an internal and/or external captive portal; an external management system for managing the network devices in the wireless network; etc. 
         [0043]    The present disclosure may be realized in hardware, software, or a combination of hardware and software. The present disclosure may be realized in a centralized fashion in one computer system or in a distributed fashion where different elements are spread across several interconnected computer systems coupled to a network. A typical combination of hardware and software may be an access point, a network controller, etc. with a computer program that, when being loaded and executed, controls the device such that it carries out the methods described herein. 
         [0044]    The present disclosure also may be embedded in non-transitory fashion in a computer-readable storage medium (e.g., a programmable circuit; a semiconductor memory such as a volatile memory such as random access memory “RAM,” or non-volatile memory such as read-only memory, power-backed RAM, flash memory, phase-change memory or the like; a hard disk drive; an optical disc drive; or any connector for receiving a portable memory device such as a Universal Serial Bus “USB” flash drive), which comprises all the features enabling the implementation of the methods described herein, and which when loaded in a computer system is able to carry out these methods. Computer program in the present context means any expression, in any language, code or notation, of a set of instructions intended to cause a system having an information processing capability to perform a particular function either directly or after either or both of the following: a) conversion to another language, code or notation; b) reproduction in a different material form. 
         [0045]    As used herein, “digital device” generally includes a device that is adapted to transmit and/or receive signaling and to process information within such signaling such as a station (e.g., any data processing equipment such as a computer, cellular phone, personal digital assistant, tablet devices, etc.), an access point, data transfer devices (such as network switches, routers, controllers, etc.) or the like. 
         [0046]    As used herein, “access point” (AP) generally refers to receiving points for any known or convenient wireless access technology which may later become known. Specifically, the term AP is not intended to be limited to IEEE 802.11-based APs. APs generally function as an electronic device that is adapted to allow wireless devices to connect to a wired network via various communications standards. 
         [0047]    As used herein, the term “interconnect” or used descriptively as “interconnected” is generally defined as a communication pathway established over an information-carrying medium. The “interconnect” may be a wired interconnect, wherein the medium is a physical medium (e.g., electrical wire, optical fiber, cable, bus traces, etc.), a wireless interconnect (e.g., air in combination with wireless signaling technology) or a combination of these technologies. 
         [0048]    As used herein, “information” is generally defined as data, address, control, management (e.g., statistics) or any combination thereof. For transmission, information may be transmitted as a message, namely a collection of bits in a predetermined format. One type of message, namely a wireless message, includes a header and payload data having a predetermined number of bits of information. The wireless message may be placed in a format as one or more packets, frames or cells. 
         [0049]    As used herein, “wireless local area network” (WLAN) generally refers to a communications network links two or more devices using some wireless distribution method (for example, spread-spectrum or orthogonal frequency-division multiplexing radio), and usually providing a connection through an access point to the Internet; and thus, providing users with the mobility to move around within a local coverage area and still stay connected to the network. 
         [0050]    As used herein, the term “mechanism” generally refers to a component of a system or device to serve one or more functions, including but not limited to, software components, electronic components, electrical components, mechanical components, electro-mechanical components, etc. 
         [0051]    As used herein, the term “embodiment” generally refers an embodiment that serves to illustrate by way of example but not limitation. 
         [0052]    It will be appreciated to those skilled in the art that the preceding examples and embodiments are exemplary and not limiting to the scope of the present disclosure. It is intended that all permutations, enhancements, equivalents, and improvements thereto that are apparent to those skilled in the art upon a reading of the specification and a study of the drawings are included within the true spirit and scope of the present disclosure. It is therefore intended that the following appended claims include all such modifications, permutations and equivalents as fall within the true spirit and scope of the present disclosure. 
         [0053]    While the present disclosure has been described in terms of various embodiments, the present disclosure should not be limited to only those embodiments described, but can be practiced with modification and alteration within the spirit and scope of the appended claims. Likewise, where a reference to a standard is made in the present disclosure, the reference is generally made to the current version of the standard as applicable to the disclosed technology area. However, the described embodiments may be practiced under subsequent development of the standard within the spirit and scope of the description and appended claims. The description is thus to be regarded as illustrative rather than limiting.