Design And Implementation Of Network Firewall Based On Loongson 2H Processor

Network security is the main component of information security.Consequently,creating the self-controllable network security products is crucial and urgent.Nowadays,a few domestic companies that produce network security products have achieved advanced international standards in software field.However,we are still using imported processors on the hardware platform.INTEL is taking up the dominant role in the CPU field.As a result,CPU,as the key components and parts for hardware framework,is playing a vital role in device security and reliability.So it can be seen that replacing foreign chips with domestic chips is particularly important.This thesis applies domestic 64 bits advanced performance processor Loongson 2H SOC chip design and achieved a network firewall system.In terms of hardware,it has completed the development based on Loongson 2H firewall motherboard: Firstly,it's structured according to the features of 2H processor hardware design;then,it follows the modular design method to complete the circuit schematic;Finally,it finishes the PCB layout based on the high-speed signal board design process.In terms of software,the focus is on the design of the underlying software PMON porting: mainly contains initialization of the stack pointer,initialization of debugging serial port,setting the CPU address window,cache initialization,serial port driver,development of network card driver,and finally PMON coding.There are two aspects of technical difficulties in this thesis,namely,the integrity of high-speed circuit board signal and integrity of power.Such difficulties have been solved by the following methods: Increases the characteristic impedance on key signal line to solve the reflection problem;Uses advanced physical constraints,namely the Cadence components Constraint Manager to set spacing constraints,routing and layer constraints to solve the crosstalk problem;Uses well-designed topology and increases bypass capacitor to solve the power problem.This thesis tests and analyzes the function,stability,reliability and network performance of Loongson 2H firewall system such as packet forwarding,delay,number of concurrent connections and number of new connections.The result shows that the Loongson 2H firewall has complete functions,high performance and good stability.Especially in the packet forwarding,it is better than the current mainstream low-end firewall products Intel IXP425.After the completion of the design,it can be applied in information security-demanding fields,including military,party and government,energy,transportation,etc.