ANALYSIS OF COMMUNICATION ARCHITECTURE OF GCDC 2011 MOHAMMADREZA KHAKSARI This thesis is presented as part of Degree of Master of Science in Electrical Engineering Bleknige Institute of Technology August 2011 Blekinge Institute of Technology School of Engineering Department of Telecommunication and Signal Processing Supervisors: Dennis Sundman, Royal Institute of Technology Dr. Henrik Pettersson, SCANIA CV AB Examiner: Dr. Jörgen Nordberg, Blekinge Institute of Technology Mohammadreza Khaksari Telecommunication and Signal Processing, BTH 2 Abstract This thesis report presents a method to analyze the communication architecture for the Intelligent Transportation Systems (ITS). The report also includes a case study on ASN.1 notation and analysis of its encoding rules. Included in the report is also: (i) accompanying instruction on how to use ASN.1 compilers to produce the C/C++ message encoder/decoder, and (ii) analysis of Non-IP communications of Communication Access for Land Mobiles (CALM-FAST) protocol stack in ITS. The thesis is a part of the research project entitled “SCOOP”, a joint project between SCANIA CV AB and KTH. Interested readers are referred to see scoop web site.1 The purpose of this thesis is to contribute to the ultimate goal, which is to equip a vehicle with necessary hardware and software technology to provide a platooning behavior in the GCDC 2011 competition. This goal is achieved by the means of wireless communication system for both vehicle to vehicle and vehicle to road side units communications in the platoon, [1]. Overall, this thesis introduces the important usage of ASN.1 in implementation of cut- edge telecommunication systems especially in V2V and V2I communication; and clarifies the CALM-FAST protocol stack in mobile nodes. 1 http://scoop.md.kth.se Mohammadreza Khaksari Telecommunication and Signal Processing, BTH 4 Acknowledgments I would like to express my gratitude to Prof. Magnus Jansson and Prof. Mats Bengtsson from KTH for giving me the opportunity to work on communication architecture of GCDC 2011. Specially, I would like to thank Dennis Sundman for his support, encouragement, discussions and comments on my thesis. I would like to express my gratitude to Dr. Henrik Pettersson, SCANIA senior engineer, for sponsoring my thesis. I want to thank Dr. Jörgen Nordberg for taking responsibility of examining my thesis. Finally, I am forever grateful to my wife, Shirin, for her patience, endless love and support for my work. She moved with me to Sweden, she always stands by me, and she has given our life together so much happiness. Table of contents Abstract ................................................................................................ 3 Acknowledgments ................................................................................ 5 Table of contents .................................................................................. 6 Glossary ................................................................................................ 8 Outline ................................................................................................ 12 1. Introduction ................................................................................. 13 1.1 Background ....................................................................................... 13 1.2 Purpose and Objectives ..................................................................... 14 1.3 Master thesis project phases ............................................................ 15 2. Analysis of Encoded and Decoded GCDC Messages using ASN.1 Packed Encoding Rules ...................................................................... 16 2.1 Introduction ...................................................................................... 16 2.2 Benefits of ASN.1 .............................................................................. 17 2.3 ASN.1 Encoding Rules ...................................................................... 19 2.3.1 Basic Encoding Rules ............................................................................. 19 2.3.2 XML Encoding Rules .............................................................................. 21 2.3.3 Packed Encoding Rules .......................................................................... 21 2.3.4 Encoding Rules Comparison .................................................................. 23 2.4 The OSI Approach of ASN.1 .............................................................. 24 2.5 ASN.1 Primary Type Definition ......................................................... 24 2.5.1 ASN.1 Type Diagram ............................................................................. 24 2.5.2 The Constructor SEQUENCE ................................................................ 26 2.5.3 The Type ENUMERATED ....................................................................... 26 2.5.4 The Constructor CHOICE ...................................................................... 27 2.5.5 The Type INTEGER ................................................................................ 28 2.6 Using the ASN.1 Compiler (ASN1C) ................................................. 29 2.6.1 Introduction to the ASN.1C ................................................................... 29 2.6.2 Use of the ASN1C to compile GCDC.ASN1 ........................................... 31 2.6.3 A sample GCDC Message....................................................................... 32 2.6.4 PER Binary view ..................................................................................... 33 3. Analysis of GCDC Communication Protocol Stack in Intelligent Transport Systems ............................................................................. 37 3.1 Introduction ...................................................................................... 37 3.2 Introduction to Protocols .................................................................. 38 3.3 CALM Communication Protocol Stack .............................................. 38 3.3.1 Application Block (Facilities layer) ........................................................ 39 3.3.2 Network Block (Network and Transport layer) ..................................... 39 3.3.3 Physical / Link Block (Access Layer) ..................................................... 39 3.3.4 CALM Management Block ..................................................................... 39 3.4 CALM Architecture ........................................................................... 40 3.4.1 CALM Service Access Point ................................................................... 40 3.4.2 CALM Management ............................................................................... 41 3.5 CALM-FAST Frame Structure ........................................................... 42 3.5.1 CALM-FAST Network Protocol Data Unit (NPDU) ............................... 42 3.5.2 Network Header ..................................................................................... 44 3.5.3 Transport Protocol Data Unit (TPDU) ....................................................... 44 3.5.4 Service Table Advertisement (STA) ....................................................... 45 3.5.5 Service Table context (STC) .................................................................. 46 3.5.6 Data Exchange ....................................................................................... 47 3.6 CALM-FAST Frame Flow .................................................................. 48 3.7 GCDC Communication Protocol Stack .............................................. 49 3.7.1 Physical and Medium Access Control Layers ........................................ 50 3.7.2 LLC Layer ............................................................................................... 50 3.7.3 Network Layer ....................................................................................... 50 3.7.4 Transport Layer ..................................................................................... 51 3.7.5 Session Layer ......................................................................................... 51 3.8 GCDC Frame Structure ..................................................................... 51 4. Summary and Conclusion ............................................................. 53 5. Future recommendation ............................................................... 54 6. References .................................................................................... 55 7. Appendices ................................................................................... 57 7.1 Appendix 1- Generated Files from GCDC.ASN1 by using ASN1C .... 57 7.2 Appendix 2- Generated encoders/decoders for BER, XER and PER . 57 7.3 Appendix 3- Produced binary files by the test program ................... 57 7.4 Appendix 4- The TPDU of GCDC message ........................................ 58 Glossary Access Layer – It is a block in CALM stack that specifies physical interfaces for different type of CALM protocol such as CALM-IR, CALM-M5, CALM-MM and CALM-FAST. ACK – Acknowledgment. An acknowledgment in telecommunication is a signal passed between communicating processes to indicate acknowledgment. ACTP – Assisted Communication Transactions Parameter ADAS – Advanced Driver Assistant Systems API – Application program Interface A-SAP – Application Service Access Point ASN.1 – Abstract Syntax Notation One. In telecommunications ASN.1 is used to present structure