CN102984075A

CN102984075A - Programmable router based on NetFPGA

Info

Publication number: CN102984075A
Application number: CN2012105471149A
Authority: CN
Inventors: 唐红; 张健; 徐川; 赵国锋
Original assignee: Chongqing University of Post and Telecommunications
Current assignee: Chongqing University of Post and Telecommunications
Priority date: 2012-12-17
Filing date: 2012-12-17
Publication date: 2013-03-20
Anticipated expiration: 2032-12-17
Also published as: CN102984075B

Abstract

The invention discloses a programmable router based on a NetFPGA (Network Field Programmable Gate Array) and relates to a computer network technology. The programmable router comprises a WWW (World Wide Web)-mode module, a CLI (Command Line Interface)-mode module, a management agent module, a programmable interface module, a communication control module, and a NetFPGA board card of a forward plane. A programming interface of the programmable router is open; users can define to realize a routing protocol and an upper layer protocol; the programmable router is not limited to an IP (Internet Protocol) tunnel mode; a uniform map forward table format is provided; the users can define a data packet processing procedure; a web and telnet management mode is provided; the users can define a function adding command; and the realizing mode based on the NetFPGA ensures a higher forward performance of the router. The programmable router based on the NetFPGA can serve as an important component of a future network test bed and be applied to verification of a new network system framework and research of a new protocol and new extension.

Description

Programmable router based on NetFPGA

Technical field

The present invention relates to the route technology of expansion able to programme, specifically based on the programmable router of NetFPGA, and efficient forwarding data bag.

Background technology

Through the development of four more than ten years, existing TPC/IP architecture can't adapt to the ICT (information and communication technology) of continuous progress and the requirement of lasting business innovation, forces people to restudy architecture and the mechanism thereof of Future Internet.

Future network research is intended to from the Internet that theory and Research on Methods and algorithm design are carried out in composition, operation principle and realization mechanism aspect substantially.Future network architecture, agreement, algorithm etc. need a large amount of theory analysises and emulation experiment before practical application, need to assess in experimental network architecture and verify.But because the conventional router closure, existing the Internet arrangement with verify that new architecture, New Deal, algorithm are very difficult.Router is as network core device, and the aspects such as its programmability, reconfigurability, manageability become more important.Programmable router allows the user to be configured or programmes, and new architecture and the protocol stack of rapid deployment on an actual physics network can effectively solve the problem that conventional router is disposed the agreement difficulty like this.It demonstrates great advantage and distant view at aspects such as flexibility, dynamic, extensibility, manageability and programmability.

Programmable router not only has the router forwarding capability, and possesses customizability.By simple programmed configurations, can move a kind of New Deal, can verify agreement thus.Similar with conventional router, it comprises control plane, Forwarding plane, and control plane is responsible for route calculating, routing table maintenance, routing management etc., and Forwarding plane uses NetFPGA fast-forwarding packet.

At present, immediate with the present invention is a kind of programmable router, uses Click and XORP to realize.XORP is intended to solve the closure of commercial router, and an opening, extendible router software platform are provided, and makes things convenient for the researcher to dispose and realizes Routing Protocol.Click be one for the modularization programmable platform on router data plane, its objective is at datum plane and realize the flexibly reusability of functional configuration and module.Router is on integral body realizes, control plane adopts XORP to finish the functions such as route calculatings, routing table maintenance, and Click mainly finish datum plane the protocol stack processing, packet is searched with the function such as transmit.Weak point is that this router is still realized based on ICP/IP protocol, and is limited to the non-ip protocol disposal ability.For making things convenient for the test of New Deal, need to support non-ip protocol, break away from the constraint of TCP/IP.In addition, the implementation of Click has determined the forwarding that its forwarding to packet is software view, has determined that the relative example, in hardware of its forwarding performance is not high.The checking of New Deal needs production environment, needs relatively high forwarding performance.

Summary of the invention

For the above-mentioned deficiency of prior art, the invention discloses a kind of novel programmable router, not only can support the IP tunnel form to realize New Deal, new expansion, and support the clean-slate thought of checking future network, support to dispose non-ip protocol.A kind of higher forwarding performance is provided in addition, is used for the checking of agreement, algorithm, architecture.

The present invention relates to a kind of programmable router based on NetFPGA, comprise control plane and Forwarding plane.Wherein control plane comprises WWW-mode module, CLI-mode module, administration agent module, programmable interface module and communication control module.

The WWW-mode module is used for providing the web-based management service, finishes information inspection and configuration WWW-mode module to router by the web mode.For the user provides the web-based management interface, make the user can be by this interface configurations New Deal, configuration router port mac address, check the logical forwarding table, check the information such as router flow status.

The CLI-mode module is used for providing the telnet service, for the user provides a telnet command line interface interface, makes the user manage configuration to router by the order behavior.

The administration agent module, be used for providing the bottom data support of WWW-mode service and CLI-mode service, create the global variable represent router current state, WWW-mode service and CLI-mode service are registered to the administration order chained list of global variable, expand new function to make things convenient for; Receives user's, and be actual executable function with command interpretation, read the information such as the current logical forwarding table of programmable router, data packet transceive state.Global variable comprises router present flow rate state, shines upon and transmit chained list, protocol identification, port information, administration order chained list and user-defined variable.

The programmable interface module for the interface that user defined logic interface is provided, comprises shining upon and transmits (Map Forward Information Table) interface, transmits the mapping of upgrading in the hardware (NetFPGA) when changing in mapping and transmits; With processing data packets function interface (packet_handler), the user finishes the self-defining data bag and processes, and the self-defining processing data packets function of registered user is finished self-defining initialization; This module is by using unified MFIT(mapping to transmit) the compatible various New Deals of mechanism, (as shown in Figure 4) wherein the list item of MFIT be normal address SA (standard address), next hop address MAC address, port (interface) to be transmitted.SA (standard address) for the New Deal destination address through formed fixed length logical address after the Hash calculation, MAC address is the MAC Address of down hop, interface is the interface of down hop.Realize the maintenance of logical mappings table and the processing of abnormal data bag by the self-defining processing data packets function of registered user (packet_handler).The user realizes self-defining setup code, is registered as the user_init in the route system, calls during by system initialization.The user can increase the custom feature order, is registered in the order chained list of router, has increased the opening of system.

Communication control module is used for providing control plane and Forwarding plane to carry out mutual interface function, and the calling data bag is processed function interface when receiving the packet that Forwarding plane sends up, calls registered custom data bag processing function; When control plane sends packet to Forwarding plane, realize the Packet Generation interface with the libnet storehouse, custom data is sealed dressed up the transmission of Ethernet data bag.The interactive information of this module has two kinds: data flow and control information stream.Data flow comprises route data packets and abnormal data bag; Control information stream comprises transmits data, initialization of register and configuration data.Communication control module has shielded bottom hardware, adopt libnet storehouse (low profile interface function library, structure, processing and the sending function of lower layer network packet are provided) the construction data bag sends, use libpcap storehouse (network packet is caught function library) monitoring reception data, by the ioctl function realize to the configuration of register with read.

Forwarding plane adopts NetFPGA to finish the forwarding data bag.NetFPGA standard router UDP(user data channel) mainly comprises input judging module, output port enquiry module, output queue module.Wherein the output port enquiry module is rewritten as above-mentioned mapping and transmits and search module, Hash calculation is carried out in packet rs destination address that at first will be to be transmitted, then in transmitting, mapping searches corresponding list item, if not then this packet is uploaded control plane process, if have then revise the packet header MAC Address according to list item, add the corresponding port forwarding queue.

Forwarding plane receives packet, whether the New Deal identification marking that at first arranges in protocol identification according to the user is judged this packet is New Deal, process if not then being uploaded to control plane, if it is according to the logic destination address original position of the New Deal that arranges, logic destination address length is taken out destination address, adopt hash algorithm to be converted to the normal address of fixed length 8 bytes, searching mapping transmits, not finding corresponding entry then to be uploaded to control plane processes, according to the purpose next hop address that finds, port to be transmitted, Update Table bag purpose next hop address, and deliver to corresponding down hop port output queue to be transmitted.

The present invention mainly adopts mapping to transmit MFIT mechanism and realizes it to the extensibility support of New Deal with registration packet processing function, adopts the NetFPGA programmable hardware to realize the efficient forwarding of packet.When not only guaranteeing programmability but also possess higher performance, meet the requirement of future network test bed, the various New Deals of convenient checking.Good interactive interface is provided simultaneously, has comprised web-based management interface and telnet command mode, the user can check the present flow rate state, transmit information, conveniently manages configuration.

Of the present invention based on the programmable router of NetFPGA and traditional programmable router comparison, have the following advantages:

The route flow process of tradition sealing is opened to User Defined processing data packets function.

Web-based management and telnet management is provided, and the user can carry out secondary development on this basis, enriches the router administration function.

Provide unified mapping to transmit MFIT, simpler on the structure, be beneficial to fast-forwarding.

Forwarding plane realizes possessing higher forwarding performance based on NetFPGA, traditional programmable router all is software router, and forwarding performance is not high.

Based on the layer two MAC agreement, can verify the three-layer network agreement, be more conducive to the checking of new network system framework, traditional programmable router generally adopts the mode of IP tunnel to verify other agreement based on the IP agreement, and implementation is complicated.

Should can be used as based on the programmable router of NetFPGA the important component part of future network test bed, be applied to the checking of new network system framework, the research of New Deal, new expansion.

Description of drawings

Fig. 1 is the programmable router architecture;

Fig. 2 is WWW-mode module realization flow figure;

Fig. 3 is CLI-mode module realization flow figure;

Fig. 4 transmits MFIT item form for mapping;

Fig. 5 is the programmable router workflow diagram.

Embodiment

Be illustrated in figure 1 as the programmable router architectural schematic, this system is mainly by forming with lower module: the NetFPGA integrated circuit board of WWW-mode module, CLI-mode module, administration agent module, programmable interface module, communication control module, Forwarding plane.

1. WWW-mode module, this module provides the web-based management interface, make the user can be by this interface configurations New Deal, configuration router port mac address, check the information of transmitting, check the information such as router flow status.At first create ServerSocket, monitor 8080 ports, when receiving request, just the client socket that produces is pressed into the formation of www request task.Create simultaneously a capacity and be 10 thread pool, used this thread pool to process the www request, reduced server consumption.Show that such as Fig. 2 the www request processing thread at first obtains task queue Line Procedure Mutually-exclusive lock, then checks whether there is untreated request in the formation.If not then discharge the thread mutual exclusion lock and withdraw from, circular wait enters inspection again.If have, then win a task, discharge the thread mutual exclusion lock next step operation is carried out in this request.Check whether this request is standard HTTP form, receive data obtains url and the parameter information of user's request.

The url that submits to for the user detects, and four kinds of results are arranged.Request list, namely the user asks all orders of current support, the command list (CLIST) of registering in the inquiry global variable, text mode is returned.Check state, flow information in the querying router global variable, the text mode return data, this flow information is by a state thread real-time servicing.Action command, i.e. configuration order, the viewing command of user's input, at first registered order in the string matching global variable, return command is processed handle, imports the parameter of user's input into to handle, and carry out respective function and process, after processing finishes, return results.For the url of other nonrecognition, the unified router First page information that returns.

2. CLI-mode module, this module provides a telnet command line interface interface, makes the user can operate simply efficiently router, thereby router is managed configuration.Show such as Fig. 3, at first create socket, monitor 23 ports, then socket is passed to sub-thread process when receiving connection request.After the request content that receives being filtered out the meaningless characters such as line feed, carriage return, in the registered order of system, carry out matching operation, find process handle after, call correlation function and process return results.

3. administration agent module, this module provides WWW mode service and the support of CLI mode service bottom order data.Create and safeguard the structure variable current_state of an overall situation, this structure relates to current all state informations of router, mainly comprise flow status, shine upon and transmit chained list, protocol identification, port information, administration order chained list and User Defined part, such as the processing data packets handle.The Ordered Registration that this module is used web-based management and telnet management is in current_state administration order chained list, and receives user's carries out the chained list traversal, finds the corresponding command handle and processes.The order of supporting has:

Flow status output: flow status structure among the current_state is read in this order, returns to the requestor with textual form.The reception that comprises four ports sends byte number, receive send number-of-packet, because the number-of-packet that queue full abandons, because the number-of-packet that verification unsuccessfully abandons.Simultaneously with the flow condition line journey that has of this function cooperating, this thread is daemon thread, when system initialization, start, its function is that the register read interface that provides by communication control module reads the value of NetFPGA correlation behavior register in real time, namely receive to send the information such as byte number, with deposit data in the flow status member of current_state.

Output is transmitted in mapping: read the every terms of information that current_state output mapping is transmitted, return and call.

Static mappings is transmitted configuration: add static that the deletion mapping is transmitted, during interpolation the logic destination address is converted to standard address after, write the current_state mapping and transmit.Write NetFPGA hardware after monitoring variation by daemon thread.

The protocol identification configuration: configuration New Deal identification marking, logic destination address original position, logic destination address length write the current_state structure.The register read-write interface that the calling communication control module provides writes NetFPGA hardware.

Port information output: the MAC Address, the logical address that read four ports of current_state output.

The port information configuration: MAC Address, the logical address of four ports of configuration write the current_state structure.The register read-write interface that the calling communication control module provides writes NetFPGA hardware.

In addition, the user can realize self-defining command functions as required, and registration enters the administration order chained list, and namely can be router increases new function.

4. the programmable interface module is mainly used in docking with user defined logic interface.The invention provides mapping and transmit (Map Forward Information Base) mechanism, the routing table that non-ip protocol and IP agreement are safeguarded when the operation is converted to the mapping of reference format and transmits, Forwarding plane only need be searched mapping and transmit when transmitting, revise head target MAC (Media Access Control) address, source MAC according to list item, send into the corresponding port transmit queue.

MFIT is transmitted in mapping, and as shown in Figure 4, its structure is standard address, mac, interface.Wherein standard address is that the packet rs destination logical address is through the value after the Hash mapping, 8 bytes; Mac is purpose mac address to be transmitted, 6 bytes; Interface is port to be transmitted, 1 byte.The user can realize routing table, the ARP table in the similar conventional router, then both corresponding list items is processed generating MFIT, just must the logical address of New Deal definition be shone upon through the hash function that system provides when generating SA.

Under the default conditions, the processing data packets function can not done any processing to the packet that receives, and is fully open to the user herein, needs User Defined to adapt to the processing data packets function of New Deal, and is registered in the packet_handler among the current_state.Use a packet daemon thread, when receiving new packet, call packet_handler and process.The user realizes safeguarding the necessary code of MFIT among the current_state, as required the packet that receives is carried out associative operation.In addition, the processing of abnormal data bag also here realizes.The user realizes self-defining setup code, is registered as the user_init among the current_state, unified call during by system initialization.The user can realize some self-defining command functions, is registered in the administration order chained list, can call when management router.

5. communication control module mainly provides upper layer software (applications) and NetFPGA integrated circuit board to carry out mutual interface function.Comprise two class functions, the reception of packet and transmission, the reading and disposing of control information.

Packet receives and adopts the libpcap storehouse to monitor realization, and libpcap catches the Ethernet data bag, calls packet_handler and is for further processing; Packet Generation provides the interface that sends Ethernet data, and the user will construct the good packet more than two layers and import into, then uses libnet storehouse structure Ethernet data bag to send.Reading and disposing of control information uses ioctl to realize, drives by control NetFPGA standard, realizes pci bus communication, the DMA transfer of data.

6. the hardware Forwarding plane is realized based on NetFPGA, uses the efficient forwarding data bag of NetFPGA.This part has been revised the forwarding module part on the basis of NetFPGA standard router.NetFPGA standard router UDP mainly comprises input_arbiter module, output_port_lookup module, oq_queues module.Revising the output_port_lookup module is written as above-mentioned mapping and transmits and search module.It is when processing the Ethernet data bag, and whether the New Deal identification marking that at first arranges in the protocol identification configuration order according to the user is judged this packet is New Deal, processes otherwise be uploaded to control plane.If be New Deal then take out destination address according to the logic destination address original position, logic destination address length of the New Deal of configuration, be converted to the SA of fixed length 8 bytes through hash algorithm, search mapping and transmit, do not find corresponding entry then to be uploaded to control plane and process.According to the purpose MAC that finds, interface, Update Table bag target MAC (Media Access Control) address, and deliver to corresponding down hop port output queue.

Figure 5 shows that the initialization procedure of programmable router system, detailed step is as follows:

1. set up global variable current_state, carry out initialization, comprise and set up that thread lock, mapping are transmitted, routing state, protocol identification, port information, administration order chained list etc.The initialization administration agent, i.e. Accreditation System order is to the order chained list, and these orders can be called by web mode or telnet mode.

2. initiating hardware reads configuration file, the MAC Address of four ports of configuration, and the configuration mapping is transmitted.This configuration file can be by user's change before system starts.Enter the User Defined part, call the usr_init handle, this function is realized and is registered among the global variable current_state by the user, the self-defining structure of initialization and start some necessary threads.

3. start successively a series of daemon threads: the creation state daemon thread, for the flow information of each port of real-time update router; Create mapping and transmit daemon thread, information is transmitted in the mapping that is used for the real-time update router; Create the packet receiving thread, receive and send to the packet that software layer is processed, the packet_handler of invoke user registration processes; Create the WWW thread, the WWW-mode service namely is provided, wait for that the user connects, and process connection request; Create the CLI thread, the CLI-mode service namely is provided, wait for that the user connects, and the order of process user input.

Claims

1. based on the programmable router of NetFPGA, it is characterized in that: comprise control plane and Forwarding plane, described Forwarding plane adopts NetFPGA to finish the forwarding data bag, and described control plane comprises:

The WWW-mode module is used for providing the web-based management service, finishes information inspection and configuration WWW-mode module to router by the web mode;

The CLI-mode module is used for providing the telnet service, makes the user manage configuration to router by the order behavior;

The administration agent module, be used for providing the bottom data support of WWW-mode service and CLI-mode service, create the global variable represent router current state, WWW-mode service and CLI-mode service are registered to the administration order chained list of global variable, expand new function to make things convenient for;

The programmable interface module for the interface that user defined logic interface is provided, comprises shining upon and transmits interface, transmits the mapping of upgrading in the hardware when changing in mapping and transmits; With the processing data packets function interface, the user finishes the self-defining data bag and processes, and the self-defining processing data packets function of registered user is finished self-defining initialization;

Communication control module is used for providing control plane and Forwarding plane to carry out mutual interface function, and the calling data bag is processed function interface when receiving the packet that Forwarding plane sends up, calls registered custom data bag processing function; When control plane sends packet to Forwarding plane, realize the Packet Generation interface with the libnet storehouse, custom data is sealed dressed up the transmission of Ethernet data bag.

2. described programmable router based on NetFPGA according to claim 1 is characterized in that: described mapping is transmitted and is comprised normal address, next hop address, port to be transmitted.

3. described programmable router based on NetFPGA according to claim 1 is characterized in that: described global variable comprises that router present flow rate state, mapping transmit chained list, protocol identification, port information, administration order chained list and user-defined variable.

4. according to claim 1 or 3 described programmable routers based on NetFPGA, it is characterized in that: described Forwarding plane receives packet, whether the New Deal identification marking that at first arranges in protocol identification according to the user is judged this packet is New Deal, process if not then being uploaded to control plane, if it is according to the logic destination address original position of the New Deal that arranges, logic destination address length is taken out destination address, adopt hash algorithm to be converted to the normal address of fixed length 8 bytes, searching mapping transmits, not finding corresponding entry then to be uploaded to control plane processes, according to the purpose next hop address that finds, port to be transmitted, Update Table bag purpose next hop address, and deliver to corresponding down hop port output queue to be transmitted.