**3.2.2 Wireless Access in Vehicular Environments**

The design of an efficient communication protocol in the automotive sector that deals with privacy, security, multi-channel operation and management of resources is a difficult task, which is under intensive scientific investigation. This task is assigned to a special IEEE working group and the ongoing suite of protocols is the IEEE 1609, mostly known as Wireless Access in Vehicular Environments or simply WAVE (WAVE, 2007).

The WAVE standards define an architecture and a complementary, standardized set of services and interfaces that collectively enable secure V2V and V2I wireless communications. Together these standards provide the foundation for a broad range of

standardised by ISO and ETSI. The most important of them, namely DSRC, WAVE and

Dedicated Short Range Communications (DSRC) is a short to medium range communications service that supports both public safety and private operations in V2V and V2I communication environments (DSRC, 2003). DSRC is meant to be a complement to cellular communications by providing very high data transfer rates in circumstances where minimizing latency in the communication link and isolating relatively small communication

DSRC is designed for vehicular wireless communications and operates on radio frequencies in the 5.725 to 5.875 GHz (Industrial, Scientific and Medical - ISM) band in Europe and in the 5.850 to 5.925 GHz band in the United States. DSRC systems consist of Road Side Units (RSUs) and On Board Units (OBUs) with transceivers and transponders. The DSRC standards specify the operational frequencies and system bandwidths, but also allow for

The range of communication using DSRC is up to 1000m with data rates of 6–27 Mb/s, where vehicles may be moving at speeds up to 140 km/h. As mentioned previously, DSRC is divided into two types of communication, namely V2V and V2I. V2V communication is used when vehicles need to exchange data among themselves in order for co-operative applications to work properly, whereas V2I communication is used when roadside units are part of the co-operative application. In co-operative systems, some applications are required to send messages periodically (e.g. every 100ms), whereas other applications send messages

At this point it should be highlighted that DSRC systems are used in the majority of European Union countries, but these systems are currently not totally compatible. Therefore, standardization is essential in order to ensure pan-European interoperability, particularly for applications such as electronic fee collection, for which the European Union imposes a

Standardization will also assist with the provision and promotion of additional services using DSRC, and help ensure compatibility and interoperability within a multi-vendor

The design of an efficient communication protocol in the automotive sector that deals with privacy, security, multi-channel operation and management of resources is a difficult task, which is under intensive scientific investigation. This task is assigned to a special IEEE working group and the ongoing suite of protocols is the IEEE 1609, mostly known as

The WAVE standards define an architecture and a complementary, standardized set of services and interfaces that collectively enable secure V2V and V2I wireless communications. Together these standards provide the foundation for a broad range of

Wireless Access in Vehicular Environments or simply WAVE (WAVE, 2007).

optional frequencies which are covered (within Europe) by national regulations.

CALM, are illustrated below.

zones are important.

when an event occurs.

environment.

need for interoperability of systems.

**3.2.2 Wireless Access in Vehicular Environments** 

**3.2.1 Dedicated Short Range Communications** 

applications in the transportation environment, including vehicle safety, automated tolling, enhanced navigation, traffic management and many others.

The architecture, interfaces and messages defined in WAVE support the operation of secure wireless communications among vehicles and between vehicles and the road infrastructure. Applications can use these standards in conjunction with equipment operating at 5.9 GHz to provide, for example, services for drivers, road operators, facilities operators and maintenance staff.

The IEEE 1609 Family of Standards for WAVE consists of four trial use standards which have full use drafts under development and two unpublished standards under development:

 *IEEE P1609.0 - Draft Standard for Wireless Access in Vehicular Environments (WAVE) – Architecture* This standard describes the WAVE architecture and services necessary for multi-

channel DSRC/WAVE devices to communicate in a mobile vehicular environment.

 *IEEE 1609.1-2006 - Trial Use Standard for Wireless Access in Vehicular Environments (WAVE) - Resource Manager* 

This standard specifies the services and interfaces of the WAVE Resource Manager application. It describes the data and management services offered within the WAVE architecture. It defines command message formats and the appropriate responses to those messages, data storage formats that must be used by applications to communicate between architecture components, and status and request message formats.


This standard will define the services and secure message formats necessary to support secure electronic payments.

Additionally, the IEEE 1609 standards rely on IEEE P802.11p. This proposed standard specifies the extensions to IEEE 802.11 that are necessary to provide wireless communications in a vehicular environment.
