DEEP-3 Decryption and Encryption of MP3

Structure of Presentation Project Brief Aims and Goals Partitioning Design Route ASIP Design Route Application Choice Project Management Early Feedback What Next Conclusions

Project Brief Problem –How easy is it to harness the power of re- configurable computing? –How easy is it for Software Engineers?

Introduction What is re-configurable computing? –“Computing platforms whose architecture can be modified by software to suit the application in question. Such a system may take the form of a Field Programmable Gate Array (FPGA) combined with external memories and processors.” Why is it of such great interest? –Reduced development costs –Reduced time to market –Hot upgrades –Improved performance (sometimes!)

Current Trends in Reconfigurable Computing Greater number of gates / higher clock frequencies  increased performance Greater volumes  reduced costs C-like hardware description languages  development accessible to software engineers  more effort can be allocated to other parts of the project

Project Aims To investigate hardware/software co-design methods –By considering two design routes using a non-trivial application as a test-bench –By measuring amount of effort required for each design route –Using direct and indirect measures e.g. Lines of code, number of gates used and execution time Perceived complexity –Comparing the performance of the prototypes with the software only version

Project Goals To produce and demonstrate two working prototypes To benchmark the prototypes and the software only solution

Hardware / Software Partitioning

Partitioning Methodology (1) C Source developed using Rapid Application Development, then evolved to fixed point implementation –Common to both routes Profiling –Find “Hot spot” regions within the C source

Partitioning Methodology (2) Partitioning –Done manually as automated solutions are not very good –Apply partitioning rules C  Handel C Design inter/intra process communication, control and synchronisation Co-Simulation –For Verification and Validation

Partitioning Design Route Advantages –Conceptually simpler to understand –De Facto Standard therefore more applied examples –Method can be used to produce low power, low cost or high performance Disadvantages –Done manually –Repeated for every application

ASIP Design

ASIP Methodology (1) C Source same as Partitioning method Profiling same as Partitioning method –Also perform static analysis to discover instruction mix and number of registers required Instruction Set Architecture developed using coarse grain customisation GCC used as re-targetable compiler Simulate to validate making necessary changes

ASIP Methodology (2) RISC (Load Store) Architecture –Based on MIPS –Efficient pipelining –Higher degree of parallelism –Performance advantage Harvard Architecture –Difficult so use Von Neuman in early stages VLIW –Improves performance –Only If Time Allows

ASIP Design Route Advantages –Most of the development effort is writing C –More efficient use of function units than GP –Shorter time to market than more customised hardware design –Reusability Disadvantages –Extra complexity with compiler alterations

System Overview Local Storage Distributor MP3 Encoding MP3 Decoding Encrypted MP3 Decrypted MP3 Sound Sample Decrypted Decompressed Sound Sample Output Source Input Source Perceived as a non-trivial application -Both computationally intensive on their own -Different instruction mix (MP3 uses reals crypto uses integers)

Requirements Functional Requirements –Compress & Encrypt Sound –Decrypt, Decompress & Playback Non-Functional Requirements –Security –Multiple Input formats –Real Time –User Friendly

MP3 International Standard –ISO/IEC :1993 Legal Issues –Patented technology –Can be licensed Based on Psycho-Acoustics model –How the human mind perceives sound

MP3 Encoding Data sent as audio frames Difficult to generate a good perceptual model –Very few good quality implementations

MP3 Decoding Easier than encoding Intended playback through speakers via FPGA

MP3 Codec Selection Considered many alternatives –LAME, BlandEnc, Xing, FhG Criteria used –VBR, Fixed Point, Open Source, Sound Quality, Frequency of Public Domain Usage, Independent Tests LAME “best” –No Fixed Point

Cryptography Requirements –Open Standard, Industry Strength, Integrity Check, Authentication Legal Issues –Patents, Key Strengths Algorithms –Public / Private Key, One-Way Hashes, Digital Signatures

RSA Algorithm Security lies in intangibility of factoring large integers Key distribution problem –Compare Padlock & Key Algorithm based on fast modular exponentiation. –Good test of FPGA performance

RSA Walkthrough Diagram Here

Conceptual Model & Walkthrough Login –Related to encryption

Encoding & Encryption

Decryption & Playback

System Architecture DMA Host CPU (x86) RC-1000 Board (FPGA – Memory) Storage Device Memory (RAM) Sound Card SpeakersLine In CD-ROM Microphone PCI Bus IDE Bus

FPGA Board Architecture

Time Management Application developed rapidly Leave adequate time for –Testing –Integration –Implementation (Handel C) –Derived from reviewing why previous group’s system failed to be delivered on schedule

Risk Management – Identified Risks ASIP Design –No prior experience –Conceptually More challenging Resources –Limited availability of FPGA Handel C –No prior experience before project Task Complexity Time Management –Slow Start

Risk Management – Managing Risks Spiral Model –Incremental with regular reviews Buddy Buddy System Dedicated Handel C “expert” Achievable goals Plenty of Research

Early Feedback Profiling results –Early identification of “hotspot” functions as psycho analysis and Huffman coding Metrics –One week to grasp partitioning –Ten weeks to grasp ASIP design Handel C –Simple programs implemented

What Next? First Application Prototype –Software only Second Prototype –Fixed Point, software only Incrementally More Complex Handel C coding Further prototypes with the design processes

Summary Presented the project aims and vision Presented two opposing development methods Presented an overview of the application to be used Identified risks and how to manage them Presented initial results Planned further work

Conclusion Project remains on schedule Good progress made Lots more to do