Routing architecture including a compute plane configured for high-speed processing of packets to provide application layer support

The present invention provides a routing architecture including a control plane, a compute plane, and a forward plane. The forward plane provides traditional forwarding of packets to the next-hop address, along with any necessary header manipulation, while the control plane configures the forward plane and the compute plane for desired operation. The compute plane is configured for high-speed processing of packets to provide application level support, including manipulating application data in the payload of the packets during routing. The forward plane preferably implements forwarding rules using filters sufficient to forward a received packet to the next-hop address, to the compute plane for application processing, or to the control plane to facilitate control or configuration.

FIELD OF THE INVENTION

The present invention relates to processing and routing packets in a network, and in particular, to providing high-speed, application level processing on the packets during routing.

BACKGROUND OF THE INVENTION

Existing routers have limited computation capacity and offer little or no application layer support during routing. These routers are typically divided into a control plane and a forward plane. The control plane is used for basic setup and control of the router. For example, the control plane is generally used to establish routing tables used by the forward plane. The forward plane receives packets, processes the packets based on the routing tables set up by the control plane, and delivers the packets to the next-hop address or the final destination, depending on the termination point for each packet.

The forward plane in existing routers is typically limited to packet delivery based on basic header analysis and manipulation. Application layer support, such as that requiring analysis or manipulation of the packet's payload, is typically avoided. Those specially configured devices capable of providing application processing, such as firewalls, are uniquely configured for the special application wherein the routing speeds for normal routing in the forward plane are significantly impacted or the control plane is uniquely adapted to handle such processing. In either case, basic routing capability of the forward plane is inhibited. Thus, traditional network routers typically do not provide application level processing, and routing devices providing such support are only used in limited applications.

Given the general desire to distribute processing over a network, there is a need for efficient routing devices capable of providing application level processing without significantly impacting forwarding performance for the packets being processed at an application level or for those requiring only basic routing. There is a further need to provide a routing device that is readily configurable to provide various types of application support in any number of network environments.

SUMMARY OF THE INVENTION

The present invention provides a routing architecture including a control plane, a compute plane, and a forward plane. The forward plane provides traditional forwarding of packets to the next-hop address, along with any necessary header manipulation, while the control plane configures the forward plane and the compute plane for desired operation. The compute plane is configured for high-speed processing of packets to provide application level support, including manipulating application data in the payload of the packets during routing.

The forward plane preferably implements forwarding rules using filters sufficient to forward a received packet to the next-hop address, to the compute plane for application processing, or to the control plane to facilitate control or configuration. For those packets not sent to the compute plane or control plane, the forward plane will provide any necessary processing and forward the packets from an input port to an output port. Additionally, the forward plane receives packets from the control plane and the compute plane for forwarding after processing by the respective planes.

Preferably, the compute plane is implemented using high-speed field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), digital signal processors (DSP), network processors, or a combination thereof sufficient to provide processing speeds that are close to forwarding speeds of the forward plane. Further, the compute plane is preferably configurable by the control plane to provide various types of application processing. The compute plane may be configured to provide different types of application processing for different packets. The forward plane may be set to determine where to send the packets in the compute plane for processing, or the compute plane may determine how or where to process the packets upon receipt.

With the present invention, the routing device is able to perform application level processing on packets without impacting forwarding performance. The invention separates the task of control from computation to avoid negatively impacting performance for either task. A new, high-speed computation plane is provided in the routing device to handle application level processing, while the forward plane provides basic forwarding. The routing abilities of the present invention may be provided in any number of network devices, including traditional routers and media gateways capable of routing packets over homogeneous or heterogeneous networks.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides for a routing node having a separate processing plane for application layer support during routing. The application layer support may include any type of processing or network service on packet content. In addition to forward and control planes, the routing node includes a separate compute plane for processing packets according to specific applications during routing. The forward plane provides traditional forwarding, along with any necessary header manipulation, while the control plane preferably configures the forward plane and the compute plane as desired. Upon reading the following description in light of the accompanying drawing figures, those skilled in the art will understand the concepts of the invention and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of this disclosure and the accompanying claims.

The embodiments set forth below represent the necessary information to enable those skilled in the art to practice the invention and illustrate the best mode of practicing the invention. With reference toFIG. 1, a routing node is illustrated and generally referenced as10. The routing node10is divided into three primary processing planes; a control plane12, a compute plane14, and a forward plane16. Preferably, all incoming packets are received by the forward plane16through various ports interacting with a network, such as a packet-switched network. The forward plane16is configured to analyze each of the incoming packets and determine where to send each packet. In general, the incoming packets need to be forwarded on toward their final destination, to the control plane12, or to the compute plane14.

Depending on the extent or nature of any necessary manipulation of the packet, the packet may be processed by the forward plane16and forwarded to the next-hop routing node or final destination. Preferably, any packet processing provided by the forward plane16is limited to manipulating information in one or more headers of the packet as necessary in traditional routing. As depicted inFIG. 2, packets requiring only traditional routing are maintained in the forward plane16for processing and immediately forwarded to the next-hop routing node or destination.

Packets entering the forward plane16that require application level processing, which may entail manipulation of the packet's payload, are directed to the compute plane14by the forward plane16. As depicted inFIG. 3, these packets are passed through the forward plane16to the compute plane14for processing and then sent back to the forward plane16, which will forward the processed packet to the next-hop routing node or final destination.

Although additional detail is provided below, the compute plane14provides application level processing, and any necessary payload manipulation required by such processing. During processing by the compute plane14, the payload may be reviewed, removed, modified, and repacked as directed by any number of applications. The routing node10preferably supports programming and unique configuration of the compute plane14and the forward plane16.

Any number of applications may be supported through the compute plane14. For example, Internet Protocol (IP) security and secure socket layer (SSL) applications may be implemented in a routing node10using the compute plane14. Various types of multimedia applications are made possible, alone or in combination with other applications. Further, incorporating a high-speed compute plane14for application specific packet processing enables streaming applications and minimizes or eliminates the need for buffering. The compute plane14is capable of implementing virtually any type of application, ranging from carrying out mathematical operations on payloads to implementing compression and encryption algorithms. The compute plane14may also help facilitate high-speed firewalls acting as a single point of entry or distributed to provide multiple points of entry. Typically, the compute plane14operates on layer four and higher protocols that are typically application related.

In addition to traditional forwarding of incoming packets and directing packets to the compute plane14for processing, the forward plane16may direct selected incoming packets to the control plane12for basic communications with the routing node10as shown inFIG. 4. In essence, the control plane12provides overall control and configuration for the routing node10, and in particular, for the compute plane14and the forward plane16. This control may range from running diagnostics to setting configurations for the compute plane14and the forward plane16. These settings may dictate the type of processing to carry out on the incoming packets and which plane handles the processing.

Returning now toFIG. 1, the routing node10may support various services, which are groups of code or objects that implement specific functionality. Preferably, these services use Java code and may be divided into compute services18related to the compute plane14, and network services20related to the operation of the forward plane16. Each of these services cooperates with the corresponding compute plane14and forward plane16via a compute application program interface (API)22and network API24, respectively. Since the services are preferably Java compatible, the compute API22and network API24may specify interfaces for Java applications to control the respective compute plane14and forward plane16.

Preferably, the network API24can be used to instruct the forward plane16to alter packet processing through the installation of hardware or software filters that facilitate forwarding rules. These filters execute actions specified by a defined filter policy. Typically, these filters can be based on combinations of fields in the machine address, IP address, and transport headers. The filters may also be configured to trigger on a payload as well. The filter policy can define where the matching packets are delivered and can also be used to alter the packet content as noted above.

Typical packet delivery options include discarding matching packets and diverting matching packets to the control plane12or compute plane14based on the filter policy. With the present invention, a high-speed compute plane14is provided to handle such processing. Additionally, packets may be “copied” to the control or compute planes12,14or may be mirrored to a selected interface. Packets may also be identified as being part of high-priority flow; these packets can be placed in a high-priority queue and delivered accordingly. As noted, the filter policy can also cause packet and header content to be selectively altered for most of these operations. The particular plane handling the processing is capable of re-computing IP header check sums at high speeds when and if the IP header or payload is changed.

In the present invention, all control plane computations, such as installing new routing tables or parsing a new Internet Control Message Protocol (ICMP) message type, are easily accommodated through the network API24. Through the network API24, the forward plane16may provide a number of services. The applications are typically contained within the forward plane16and will not require additional processing by the compute plane14for traditional operation. The following list of services is merely exemplary and is not intended to limit the scope of the present invention.

A filtering firewall may be implemented that allows or denies packets to traverse specified interfaces depending on whether the packet header matches a given bit map. An application specific firewall may be implemented that dynamically changes the firewall rules according to the application. For example, a file transfer protocol (FTP) gateway that dynamically changes the firewall rules to allow FTP data connections to a trusted host can be implemented. Security functions like stopping Transmission Control Protocol (TCP) segments with no or all bits set can also be dynamically programmed.

Dynamic Real-Time Transfer Protocol (RTP) flow identification is possible. RTP over User Datagram Protocol (UDP) flows, which are often not well known, are identified by a UDP port number. Mechanisms can be implemented to identify RTP flows based on the UDP port number. For example, control protocol messages, such as those used in Session Initiation Protocol (SIP), Real Time Streaming Protocol (RTSP), and H.323, can be intercepted and parsed for their RTP port numbers. Various differential services may be provided. For example, the forward plane16may be configured as a differential service classifier by properly programming the filters or forwarding rules. Since the forward plane16may change selected bits and IP header at line speed, the routing node10can be used to implement ingress/egress marker capabilities for differential services. Reliable multi-casts are also made possible with proper forwarding rules.

In addition to being able to copy certain packets for inspection by the control plane12, the forward plane16may be used to divert acknowledgements from multi-cast sessions to the control plane12. For example, the forward plane16can send one copy of the acknowledgment to the control plane12and suppress duplicate acknowledgements. Additionally, a token bucket system may be arranged where a configurable buffer is implemented with a specified packet draining rate. Differential service shapers and assorted RSVP policies can be implemented as well. RSVP is a resource reservation setup protocol for the Internet. Its major features include: (1) the use of “soft state” in the routers, (2) receiver-controlled reservation requests, (3) flexible control over sharing of reservations and forwarding of subflows, and (4) the use of IP multicast for data distribution. For additional information regarding RSVP, please see the Internet Engineering Task Force's RFCs2205through2210, which are incorporated herein by reference in their entirety.

The various functions provided by the forward plane16listed above relate to analyzing incoming packets, manipulating packet headers, if necessary, and forwarding the packets to the next-hop or destination at high speeds.

The present invention supplements these abilities with high-speed, preferably line rate, processing capabilities at an application level. As noted, the compute plane14is preferably used to manipulate packet data or payloads beyond layer three or four protocols that provide application layer support. Thus, instead of analyzing or modifying the header on a packet, data analysis and manipulation associated with application layers in the packet is possible in the compute plane14.

Importantly, the compute plane14provides application support efficiently and at high speeds without impacting the traditional routing speeds of the forward plane16. Further, the application layer processing is provided at much faster speeds in the compute plane14than would be possible in the control plane12. In addition to increased routing speeds and efficiency for application support, the compute plane14allows significant configuration of routing nodes10to facilitate any number of applications or combinations thereof.

Overall interaction between the control plane12, compute plane14, and forward plane16is outlined in the flow diagram ofFIG. 5. Notably, the preferred processing for each of the three planes is illustrated. The process begins (block100) with the forward plane16receiving all incoming packets regardless of whether the packets are intended for the routing node directly or simply sent to the routing node for routing. When a packet is received (block102), the forward plane16will filter the packet based on the forwarding rules (block104).

In general, the forwarding rules will dictate whether the packet is forwarded to the control plane12, compute plane14, or sent to the next-hop or destination after processing by the forward plane16(step106). As discussed above, packets directed to the routing node10, such as those used for diagnostics or to set configurations, are directed to the control plane12. Packets requiring application level processing are sent to the compute plane14. Packets for which the forward plane16can handle all processing are simply processed in the forward plane16and forwarded to the next-hop or destination. Typically, packets processed by the compute plane14and forward plane16are those requiring routing.

Assuming that the packet is one capable of being handled solely by the forward plane16, the packet is processed accordingly in the forward plane16(block108) and forwarded to the next-hop or destination (block110). As noted, packet processing in the forward plane16is typically limited to header analysis and manipulation.

If the packet received by the forward plane16is determined to be one directed to the control plane12based on the forwarding rules (block106), the packet is received by the control plane12(block112) and processed by the control plane12accordingly (block114). As noted, packets intended for the control plane12may facilitate diagnostic or control instructions for the compute plane14, such as instructions to set particular configurations for the compute or forward planes14,16. For example, the compute plane14may receive information for establishing the forwarding rules for the forward plane16as well as configure the particular processing carried out by the compute plane14or the forward plane16.

When the control plane12needs to respond to communications or deliver instructions to another network device, the control plane12will prepare a suitable packet or response for sending to a select destination (block116). Preferably, the packet or packets associated with an outgoing communication from the control plane12are sent to the forward plane16wherein the packet or packets are forwarded to the next-hop or destination (block110).

If the packet received by the forward plane16from the network is one requiring application level support and the forwarding rules direct the packet to the compute plane14(block106), the packet is routed to the compute plane14accordingly. As described in further detail below, the forwarding rules may dictate where to send the packet within the compute plane14or how the packet will be processed once it is received by the compute plane14. In general, the compute plane14receives the packet (block118) and processes the packet as dictated by the application (block120). As noted, preferably the application data or payload is processed in the compute plane14.

In particular, the compute plane14is configured to carry out select functions to facilitate application level processing, which results in data or payload manipulation (block120). The processing may require restructuring or re-packetizing the data or payload information depending on the particular application. Certain applications may simply process individual packets wherein other applications may require various types of data or payload reconstruction. For example, information in one packet may be used to create multiple new packets, or the information in multiple packets may be used to create a single packet. Regardless of the processing, the packets processed or provided by the compute plane14are sent to the forward plane16(block122) for forwarding to the next-hop routing device or destination. As such, the forward plane16will receive packets from the compute plane14and forward the packet to the next-hop or destination (block110).

A block diagram of a preferred configuration of the switching node10is depicted inFIG. 6. Preferably, each of the control plane12, compute plane14and forward plane16includes dedicated processing capability and is in communication with the other planes through a switching backplane26. As such, the control plane12will include a control processor28associated with a backplane interface30coupled to the switching backplane26and will include sufficient memory32for storing the necessary instructions and data for operation.

The compute plane14includes a backplane interface34in communication with one or more high-speed compute processors (CP)36. These compute processors36will include or be able to carry out select processes, rules or functions38. Further, the compute processors36may stand alone or be controlled in part by a host processor40. Preferably, the host processor40is associated with sufficient memory42for storing the necessary data and instructions for operation. The host processor40may also be associated with a library module44, which may store various types of compute processor functions used to configure the function or rules38of the compute processors36. The speed of the host processor40is not as critical as insuring that the compute processors36are capable of high-speed processing.

In an effort to maximize the processing speeds, the compute processors36may be implemented using field programmable gate arrays (FPGAs); application specific integrated circuits (ASICs); digital signal processing (DSP) components; network processors; or a combination thereof. Preferably, each compute processor36will include a processor and an FPGA or ASIC cooperating to maximize processing throughput. The processor facilitates configuration of the cooperating FPGA or ASIC, while the FPGA or ASIC processes the packets. Notably, the compute processor36is a generic name for any one or combination of hardware, firmware or software capable of providing the high-speed application processing required in the compute plane14. Those skilled in the art will appreciate the numerous techniques available to provide high-speed processing.

The compute processor36is configured to carry out select functions or rules38at or close to wire-line speeds on the selected packets directed to the compute plane14from the forward plane16. Importantly, the compute processors36may provide a combination of functions for varying applications or may be configured wherein each compute processor36carries out a dedicated function or rule38. In the latter case, different compute processors36may facilitate different processing based on the function or rules38. As such, the packets sent to the compute plane14from the forward plane16are directed to a select compute processor36capable of handling the application associated with the given packet.

The forward plane16includes a backplane interface46for communicating with the switching backplane26. The backplane interface46of the forward plane16is associated with a forward processor48capable of implementing select forwarding rules50that facilitate packet filtering and delivery to the control plane12, compute plane14, and the next-hop or destination. The forward processor48provides the typical routing processing and functions in traditional fashion for those packets that do not require the application processing of the compute plane14. The forward processor48is also associated with a network interface52, which is coupled to the packet-switched network for receiving and sending packets.

The network interface52may be any type of network interface, including a 10 Base T, 100 Base T, or gigabit Ethernet interface. As depicted, given the necessary volume of traffic handled by the routing node10, the forward plane16may be provided on multiple cards, all of which interface with the switching backplane26. These cards may include their own forward processors48and network interfaces52. Further, the compute plane14may be implemented on multiple cards in a fashion similar to that depicted for the forward plane16.

As with the compute processors36in the compute plane14, the forward processors48require high-speed processing capability. As such, the forward processor48is also an ASIC, FPGA, DSP device, network processor, or combination thereof. Preferably, as with the compute processors36, the forward processors48are programmable in the sense that the forwarding rules50and basic processing configurations are programmable. Preferably, the compute processors36and the forward processors48are programmable and can be programmed under the control of the control plane12.

In essence, it is preferable for the control plane12to be able to establish the forwarding rules50and configure processing for the forward plane16. Similarly, the control plane12is preferably capable of setting the functions and rules38implemented by the compute processors36in the compute plane14. Those skilled in the art will appreciate the tremendous flexibility in programming and configuring the compute plane14and the forward plane16.

For example, assume that for a given media stream application level processing is required for type A packets and basic forwarding is required for type B packets. Configuration instructions may be sent to the routing node10defining the type A and B packets within the media stream and the processing function to provide on the type A packets. The configuration instructions may be sent in one or more packets, which will be forwarded to the control plane12by the forward plane16. Upon receipt, the control plane12will configure the forward plane16to recognize the type A and B packets in the media stream and forward the type A packets to the compute plane14and the type B packets on to the next-hop or the final destination.

Those skilled in the art will recognize that the routing node10of the present invention may be used in homogeneous as well as heterogeneous networks. For example, the routing node10may be implemented as a router in a packet-switched network or in a media gateway, bridging like or different networks. In the latter case, the compute plane14is very effective in allowing the processing of packets or content being converted from one format or protocol to another.

The present invention provides a compute plane14facilitating application processing during routing. Regardless of the processing function, the compute plane14in the routing node10allows the forward plane16to maintain the extremely high processing and forwarding speeds required for traditional routing and maximizes processing speeds for packets requiring processing at an application level during routing. The present invention allows tremendous flexibility in configuring routers and adds the ability to provide application processing at or near wire-line speeds without effecting normal routing speeds of the forward plane16or requiring additional computation power in the control plane12.

Those skilled in the art will recognize improvements and modifications to the disclosed embodiments of the present invention. For example, the routing devices of the present invention may be any number of network devices, including routers, switches, gateways, aggregation devices, network distribution devices, core routers, wireless base stations, wireless access points, and multiplexors (electrical and optical). All such improvements and modifications are considered within the scope of the concepts disclosed herein and the claims that follow.