**4. The PEGASUS project: Real time support in infomobility services**

One of the most important applications to which QoS techniques have been applied are Smart Navigation and the braoader field of Infomobility.

Transportation is one of the main fields where advanced technological systems can improve human life in a significant way: risks due to accidents, time wasted travelling and pollution could be highly reduced by applications for vehicle localization, behaviour prediction, etc.

These considerations are at the basis of the increasing interest that ITS are gaining in these years.

Furthermore, the latest study on global urbanization conducted by the Population Division of the Department of Economic and Social Affairs of the United Nations predicts that, in 2050, nearly 70% of the global population will be living in larger cities [23].

This immense aggregation of people will surely pose great challenges to the sustainability of modern lifestyle, and the problem of an efficient management of mobility stands out as one of the most relevant ones.

A Testbed About Priority-Based Dynamic

required, are still open issues.

Fig. 12. Smart navigation scenario.

negligible percentage of the overall private vehicles number).

public or private institutions for traffic management, etc.

traffic management, such as safety and entertainment.

Connection Profiles in QoS Wireless Multimedia Networks 91

and private vehicles in Italy was 34 million back to 2003 [25], hence the FCD is a not

All such data are processed and exploited for the real time dynamic navigation of vehicles (hereafter Dynamic Route Guidance, DRG); the same information can also be forwarded to

In the near future, almost all vehicles will be able to send real time information, and the majority of drivers will take profit of data properly processed and of applications beyond

In this scenario, telecommunications systems will be required to transmit information quickly and reliably, both among vehicles and between vehicles and remote control centers. Which technologies are to be chosen, how priorities must be managed, which capacity is

The mobile network is, at present, the only one adopted for vehicles-Control Center

Urban networks, thus, can turn out to be a precious support for existing infrastructures,

communication; nevertheless, the quantity and size of information is to increase.

especially if properly managed through effective QoS techniques.

As a matter of fact, densely populated cities imply the concentration (from the country) and distribution (within the city) of massive amounts of people and resources [24].

In addition to the vast economic importance and consequences of such situation, urban and sub-urban mobility is a serious challenge also due to the circulation of large amounts of people and goods in a relatively small area. This poses hazards to life and health, especially for children, the elderly, and unfamiliar visitors, as well as to the environment.

Urban mobility, in fact, accounts for some 30% of energy consumption and 70% of transport pollution in Europe, and this problem is magnified by the increasing population concentration in large cities.

In such a scenario, the efficient management of traffic is a challenge that governments, industries and researchers are forced to face worldwide. Private travellers, commercial road users, and the public sector are continually searching for new and faster travel routes and methods.

Roads efficiency can be substantially improved by the deployment of ITS, which exploit ICT in order to provide traffic safety and efficiency.

ICT can be considered as the foundation for carrying out smart navigation, meant as the paradigm where mobile entities (vehicles and pedestrians) move wisely through a given environment, exploiting reliable and timely information about traffic conditions.

In this context, one of the most important applications is the support of real time, meant as the constant monitoring of traffic and road conditions, and the consequent possible update of the routes previously suggested. As a matter of fact, the best path in a given situation can vary when traffic conditions vary and updates should be notified to the user in real time. Nevertheless, up to now, no simple and marketable product was proposed for monitoring traffic and providing real time information to road users.

To this purpose, in the framework of the Italian project PEGASUS (http://pegasus.octotelematics.com/), WiLab aims at exploiting information transmitted from vehicles to a remote Control Center, so as to provide drivers in real time with updated information about actual traffic conditions. In this way, a new smart navigation service is supported. In particular, the objective is twofold:


In Fig. 12, the smart navigation scenario considered and developed at WiLab is shown: vehicles are equipped with on-board units (OBUs), which periodically transmit their speed and position (known through the GPS integrated on board) to a Control Center. Such data are transferred through the General Packet Radio Service (GPRS) network.

The fleet equipped with OBUs is addressed as *floating car data (FCD)*. In March 2010, the Italian FCD to which the PEGASUS project refers, reached over 1.000.000 equipped vehicles (OctoTelematics, 2010); this number is to increase quickly (note that the number of public

As a matter of fact, densely populated cities imply the concentration (from the country) and

In addition to the vast economic importance and consequences of such situation, urban and sub-urban mobility is a serious challenge also due to the circulation of large amounts of people and goods in a relatively small area. This poses hazards to life and health, especially

Urban mobility, in fact, accounts for some 30% of energy consumption and 70% of transport pollution in Europe, and this problem is magnified by the increasing population

In such a scenario, the efficient management of traffic is a challenge that governments, industries and researchers are forced to face worldwide. Private travellers, commercial road users, and the public sector are continually searching for new and faster travel routes and

Roads efficiency can be substantially improved by the deployment of ITS, which exploit ICT

ICT can be considered as the foundation for carrying out smart navigation, meant as the paradigm where mobile entities (vehicles and pedestrians) move wisely through a given

In this context, one of the most important applications is the support of real time, meant as the constant monitoring of traffic and road conditions, and the consequent possible update of the routes previously suggested. As a matter of fact, the best path in a given situation can vary when traffic conditions vary and updates should be notified to the user in real time. Nevertheless, up to now, no simple and marketable product was proposed for monitoring

To this purpose, in the framework of the Italian project PEGASUS (http://pegasus.octotelematics.com/), WiLab aims at exploiting information transmitted from vehicles to a remote Control Center, so as to provide drivers in real time with updated information about actual traffic conditions. In this way, a new smart navigation service is

• investigate the impact of real time updates on traffic management efficiency; as a matter of fact, vehicles equipped with smart navigators are constantly sent information about

In Fig. 12, the smart navigation scenario considered and developed at WiLab is shown: vehicles are equipped with on-board units (OBUs), which periodically transmit their speed and position (known through the GPS integrated on board) to a Control Center. Such data

The fleet equipped with OBUs is addressed as *floating car data (FCD)*. In March 2010, the Italian FCD to which the PEGASUS project refers, reached over 1.000.000 equipped vehicles (OctoTelematics, 2010); this number is to increase quickly (note that the number of public

• investigate the impact of smart navigation on the communication networks load;

are transferred through the General Packet Radio Service (GPRS) network.

environment, exploiting reliable and timely information about traffic conditions.

distribution (within the city) of massive amounts of people and resources [24].

for children, the elderly, and unfamiliar visitors, as well as to the environment.

concentration in large cities.

in order to provide traffic safety and efficiency.

traffic and providing real time information to road users.

supported. In particular, the objective is twofold:

actual roads conditions;

methods.

and private vehicles in Italy was 34 million back to 2003 [25], hence the FCD is a not negligible percentage of the overall private vehicles number).

All such data are processed and exploited for the real time dynamic navigation of vehicles (hereafter Dynamic Route Guidance, DRG); the same information can also be forwarded to public or private institutions for traffic management, etc.

In the near future, almost all vehicles will be able to send real time information, and the majority of drivers will take profit of data properly processed and of applications beyond traffic management, such as safety and entertainment.

In this scenario, telecommunications systems will be required to transmit information quickly and reliably, both among vehicles and between vehicles and remote control centers. Which technologies are to be chosen, how priorities must be managed, which capacity is required, are still open issues.

Fig. 12. Smart navigation scenario.

The mobile network is, at present, the only one adopted for vehicles-Control Center communication; nevertheless, the quantity and size of information is to increase.

Urban networks, thus, can turn out to be a precious support for existing infrastructures, especially if properly managed through effective QoS techniques.

A Testbed About Priority-Based Dynamic

generated contents, energy management, etc.

**6. Conclusions and future QoS testbed extensions** 

through smart navigators.

stops.

place.

be based on TCP/IP.

could be relayed without PPP tunnel drops.

Connection Profiles in QoS Wireless Multimedia Networks 93

In this case, the effective management of QoS is tested in order to supply citizens with several services, such as video surveillance (both wired and wireless data transmission involved), integrated image analysis, Internet connection within urban environments, RFID services for tourists, emergency calls, radiodiffusion, fire prevention, parking management, localization, diagnostics and control by television. In addition, sensor network data collection, traffic information, access control, mobile payments, vehicle tracking, user-

Through QoS management, such services will be configured dynamically on the basis of bandwidth availability. According to the throughput actually available in a specific temporal slot and thanks to a constant monitoring of radio resources on each route, both

More specifically, the testbed is addressed to transport improvement and traffic reduction

Coming back to the tests in Sections 2, 3, PPP tunnels between the server and users can be temporarily closed, when packet transimission is slowed down by interference or machinery

The first problem is that, in case the PPP LCP surveys trouble situations, the channel is closed and the client disconnected. An authomatic procedure is in charge of reconnection, but a time waste in PPP tunnel setup as well as abrupt disconnections are bound to take

A second problem derives from traffic limitation and control being handled by a single QoS server: in this case, data are properly limited only after they have crossed one or two links. In other words, in case an authenticated user sends an UDP data flow larger than his or her maximum upload bandwidth, such flow will be diminished only after reaching the QoS server. Meanwhile, the available bandwidth will be unproperly occupied by such flow.

On the basis of such considerations, the testbed will be extended according to two different scenarios of distributed QoS architectures [26-28]. The first one is depicted in Fig. 14 and

In case many relays occur between the client and PPPoE concentrator, packet loss can increase; the idea, thus, is to shorten the tunnel, so as to integrate the PPPoE concentrator and the transmitter. In this way, all PPP features could be maintained and its limitations diminished. The tunnel, in fact, would be established between the client's CPE and the nearest transmitter and communication between the transmitter and the main server could

Furthermore, if interferences between transmitter and main server would take place, packets

A disadvantage could concern uncoded communication between the main server and pylons. Possible solutions could be the activation of encrypted systems or a PPP tunnel to

the main server. In this case, the user would not even perceive any link failure.

aims at avoiding tunnel closure in case of interference and packet loss.

services to be offered to the user and applications to be kept active can be chosen.
