Overview of VANET Project (11’) on Quadstone Paramics Perspective Jae-Myeong Lee HMCL

VANET Project VANET is shorten word of Vehicular Ad-hoc Network. Ad-hoc Network means a special-purpose network. The goal is simulation of VANET with simulator. There is no simulator for VANET simulation. Therefore we used two simulators, and each of them can simulate only one thing. These simulators are: Quadstone Paramics and NS-2 Quadstone Paramics is a traffic simulator, to simulate vehicles’ moving. NS-2 is a network Simulator, to simulate VANET. We made them interact each other with IPC. IPC(Interprocess Communication): a technique for comm. between different processes, which is supported by OS(MS-Windows).

Understanding Paramics Quadstone Paramics is developed by Quadstone, Inc. Mid-scale traffic simulator can simulate large area also can simulate details, in vehicular level. Non-freeware: commercial software. requires license key Quadstone Paramics comprises: Analyzer Analyzes simulation result Designer Design road network Modeller Configure road network, and simulate in GUI Processor Simulator, non-GUI Viewer Simulation viewer, GUI We use Modeller and Processor. ▲ Modeller, during simulation vehicle

Understanding Paramics (Cont.) Network means network of nodes, which is graph of roads. Network is a bidirectional graph in default, also can be unidirectional graph. we’re using unidirectional. A network may include: Nodes, are vertices of road graph Links, are edges of road graph Links are straight line basically, also can be arc line. Zones, are special areas where a car enters or leaves Entrance of our network, or a parking lot Loop Detectors or Detectors VMS Beacons or Beacons VMS: Visual Messaging System A network is stored as files into a directory. VMS in Maryland, US Zone 1 … … Zone 2 road(link) loop

Our project scenario Our project is pretty simple: In default, all vehicles travel around the network, in shortest path. (Paramics vehicles’ default behavior) We collect the traffic information from: Loop Detectors RSE(Road Side Equipment)s into a server. Server analyze the traffic information and calculates average speed in each links. (*In real world, it is an separated computer, but in our project, server code is in Paramics plug-in C project) Vehicles decide routing path depending on server information. (Not shortest path! Minimized-travel-time path!)

A car is moving. Loop’s entrance sensor detects the entry.Loop’s exit sensor detects the exiting.Calculate car’s speed from distance and time gapUser plug-in calls qpg_DTL_xxx(Loop API) to get statistics of vehicle speed, when needed. Our project scenario (Cont.) Explanation of some technical terms: Loop Detectors Equipment installed on the road, which detects and collects vehicles’ speed. It has two sensors, to sense vehicle’s entry and exit. Mechanism of Loop Detectors in Paramics: Node #1 Node #2 Link #1 Loop #1 Loop’s entrance sensorLoop’s exit sensor 07:05:01 07:05:06 100m 72 User Plug-In Paramics Simulator avgspeed=qpg_DTL_xxx(); Instructions:

Our project scenario (Cont.) Explanation of some technical terms: Loop Detectors But, we don’t use Paramics-managing speed statistics. To make easy to do what we want We make a callback handler for “Enter to loop” event. And when it is called: Get the vehicle’s real speed by calling qpg_VHC_speed() Send vehicle speed to server with Loop #.

Our project scenario (Cont.) Explanation of some technical terms: RSE(Road Side Equipment)s Equipment installed on the road side, which communicates cars with wireless network(DSRC) Paramics doesn’t support RSE, because it doesn’t have any network simulation features. So, we must implement RSE in plug-in code, while expressing its position with Loop Detector. RSE in concepts: Road RSE

Our project scenario (Cont.) Explanation of some technical terms: Calculation of speed with RSEs (in unidirectional): RSE#01 RSE#02 D(distance) Matched We can Calculate Vehicle #5’s speed from D and (T2-T1) Link #1 Link #2 Link #3 Link #4 Link #5Link #6 Node #1 Node #2 Node #3 Node #4 Node #5 Node #6

Paramics API Programming Already we knew, Paramics supports User Plug-ins. Plug-ins are standard Windows DLL executables, which exports callback functions A plug-in interacts with Paramics via Paramics APIs. Paramics APIs have four types: Callback Type (qpx_xxx_xxx) (e.g.: qpx_NET_postOpen) A plugin-defined function, where Paramics notifies a event to. We can just receive event notification, cannot influence simulation. Override Type (qpo_xxx_xxx) (e.g.: qpo_RTM_decision) A plugin-defined function, which overrides default Paramics action. Setter Type (qps_xxx_xxx) (e.g.: qps_GUI_printf) An API to set something’s value or status. Getter Type (qpg_xxx_xxx) (e.g.: qpg_NET_nodes) An API to get something’s value or status.

Paramics API Programming (Cont.) API Naming Convention: qp%_XXX_WordWord() % : Type of API (x = callback, o = override, s = setter, g = getter) XXX : Category of API BCN: Beacon (VMS Beacon) BUS: Bus vehicle BSR: Bus Route CFG: Configuration CLK: Clock DRW: Drawing (* Modeller Graphics) EDT: Editor LNK: Link NDE: Node NET: Network … WordWord: Action of API Example: qpg_LNK_name() : get name of a link

Paramics API Programming (Cont.) We can look up APIs we need, in Programmer Reference Manual Example: qpg_CFG_simulationTime (Getter of, Configuration, Current Simulation Time) Syntax float qpg_CFG_simulationTime(void); Description This function returns the current simulation time in seconds.

Paramics API Programming (Cont.) Simple plug-in code, prints “Hello World!”: #include // Paramics API void qpx_NET_postOpen() { qps_GUI_printf(“Hello World!\n”); // prints message to GUI } [Explanation] Programmer.h: header file for Paramics APIs qpx_NET_postOpen: callback function, which is called after network load completion qps_GUI_printf: printf function, in Paramics API

Paramics API Programming (Cont.) Handling Network Objects Almost network objects (such as Node, Link, Loop Detectors) has index #. (But, vehicle has no index, just has unique ID(car #)) Their index is put with sequential number in based-1. e.g.: 10 Nodes in network → each nodes’ indexes are 1, 2, 3, …, 10. Network Objects are expressed in pointer type. NODE *, LINK *, VEHICLE *, … We cannot dereference their pointers, just can pass them to APIs. Because, Their internal are undocumented and private. (Example - definition of NODE: typedef struct NODE_s NODE; // no definition of struct NODE_s ) Practice: Get Length of Link #11 LINK *lp = qpg_NET_linkByIndex( 11 ); // get object from index if(lp) qps_GUI_printf(“Link #11 length = %d\n”, qpg_LNK_length(lp) );

Paramics API Programming (Cont.) Our plug-in’s Visual C++ project named “TrafficPlugin”. Our C-language project includes: TrafficPlugin.c: Main plugin code SharedQueue.c: Shared circular array FIFO(queue) code Server.c: Implementation of server(traffic analyzer) ServerCaller.c: Wrapper Functions of Server Interface PacketIO.c: NS2 packet reading functions matrix.c: Functions related to adjacency matrix processing. Adjacency matrix: One of graph expressions in matrix array filter.c: (unused – temporary code) Server/*.c: (unused – temporary code)

On the next time… Look in detail NS-2 Explanation Analyze project source code Functions Tricks we used Algorithms Simulation demo Explain what we do in this year

Thank You! Any Questions?