2.6  The Level of Service and Operating Environment concept

2.6.1 Preliminary remark

Besides content and functionality also the availability and the level of service of European ITS Core services are subject of harmonisation: “Road users shall be able to expect a certain Level of service offer in a specific Road environment!”

In order to be able to bindingly define such a road class and traffic problem-based Level of Service offer, two basic concepts and one matching concept have been developed. In combination, they result in a specific ITS service setup pattern for each ITS-core service. Road operators can orient themselves on this pattern when rolling out their ITS services.

2.6.2 The Concept of Operating Environments

An Operating Environment means the category of the road section classified according to types and service levels of ITS services typically expected to be operated and often provided on it by the road authorities and operators. Thereby, the Operating Environment is closely related to the expected service levels of the travellers and hauliers using the road section, the frequently occurring or threatening problems of the section, and the feasibility of possible ITS solutions to deal with these problems. The main properties of the road section affecting the Operating Environment are its physical characteristics, network typology, and the frequency and severity of traffic flow and road safety concerns on the section.

There are 14 pre-defined Operating Environments where each Operating Environment is a combination of three criteria:

  • Physical characteristics – Motorways or other 2/3/4 lane roads
  • Network typology or traffic management orientation – Corridor, Network, Link or Critical spot —Traffic characteristics – Traffic flow and road safety situations (with optional additions).

In addition, a specific road section may be characterized by attributes such as recurring weather problems, a particular sensitivity for environmental impacts or particular importance for freight transport. The classification method allows for such attributes to be added to the Operating Environment identified.

Chapter 8 (Annex C) gives more information on the criteria and their use in the Operating Environment classification. This is essential especially, if the reader wishes to find out about the methods used for classifying whether there are road safety or traffic flow concerns or not, or if the reader wishes to make a classification of his/her road network.

The Operating Environments proposed for European ITS Core services are defined in a step-by-step approach, in which a road operator can allocate a road or a section of a road (a network element), taking into account the attributes listed above. It has to be noted that the Operating Environments are obtained through a qualitative and sequential approach, in order to make it simple and easy to use for any part of the road network.

The general layout (see Table 7) is defined according to a letter code relating to the different physical characteristics, following a slightly modified TELTEN approach (ERTICO, 1997[1])

  • C for critical spots (bridges, tunnels, reversible lane sections, etc.)
  • T for motorways
  • R for roads other than motorways
  • S for motorway corridors or networks
  • N for road corridors or networks
  • P for peri-urban road networks.

Table 7:  Operating environments for European ITS services (see also Annex C: Operating Environment Classification)

The Operating Environments can be used in a number of ways. Four frequent uses are described below.

  • Operating Environments and deployment priorities: By describing the critical spots and the sections with most severe problems and concerns, the Operating Environments can be used in selection of the parts of the road network for improvement measures as well as for prioritising between the different road segments and connections when the road operator is implementing different measures. For Europe-level assessments it would be preferable to use a consistent methodology for classifying the European road network into Operating Environments as possible.
  • Operating Environments and Service Levels-tools for deployment planning: Operating Environments can also be used to steer and harmonise the implementation of Core ITS Services by the road operators in order to achieve harmonised service composition and harmonised service levels within a certain Operating Environment. To achieve this, there needs to be a description per Core ITS Service on adequate service levels to be applied in different Operating Environments. In EU EIP, the Operating Environments were also shown to be applicable to describe the service levels of digital and communication infrastructures facilitating C-ITS services and automated driving.
  • Application of Operating Environments in Deployment Guidelines: Operating Environments are used in the Deployment Guidelines in order to guide towards a harmonised service composition. The aim is to achieve consistent service levels related to the type of road section, corridor or network in a way understandable also to the road users.
  • Operating Environments in Strategy and Road Map processes: By using the Operating Environments as the basis for the deployment strategies, road maps and action plans, rather than the physical road network, project partners can discuss deployment priorities in relation to an abstract network model, and then bring this information back into their national planning process. By adding the dimension of service level improvements and the dimension of time, the basic information required for an ITS deployment road map and action plan can be put in place.

2.6.3 The Level of Service criteria concept

In order to be able to match the road and traffic-related classification of environmental conditions with Levels of Service, a set of criteria is required according to which various service levels of ITS Core service deployments can be differentiated. These criteria provide – for each ITS Core service specifically – the so-called Level of Service criteria tables, which describe three levels of service A, B and C for all criteria. Service level category A describes a low level, level B a medium level, and level C a high service level category. Each Level of Service table provides a specific set of criteria tailored to the characteristics of the respective service. An example of such a Level of Service criteria table is provides in

Table 8:  Level of Service Criteria for the “Traffic management for corridors and networks” service

2.6.4 The Level of Service Criteria to Operating Environment relation

Once the two basic concepts “Operating Environment concept” and “Level of Service concept” have been created, both concepts can be mapped to each other. The result is a so-called “Level of Service to Operating Environment mapping table”, which depicts the minimum and optimum LoS which should be respected when the ITS-service is deployed. This is done for all ITS Core services in this handbook. Table 9 shows a Level of Service to Operating Environment mapping table using the example Traffic management for corridors and networks service. If we look for instance at the levels of services related to Availability in time, the lowest level of service A “Service periodically ensured” during critical periods is the minimum requirement (M) in all operating environments except for N2 and P1, where the minimum level is higher, B calling for extended availability in time when required. “The operating environment R1 is not expected to require the service, and therefore no requirements apply there. M marks the level of service that should be provided on all roads or road sections belonging to the specific operating environment. The level O denotes the optimal level of service, i.e. the level where the road operators should aim for in the long run. In the example, the O levels are higher than the M levels for motorways, four-lane roads, and networks with severe congestion problems i.e. for C1, T3, T4, S2 and N2. For other operating environments, the road operators do not need to reach for higher level of service than the minimum one, and thereby the marking OM is used to denote this. The highest level of service C Service “24/7 ensured” is to be aimed for only the road and motorway corridors and networks with severe congestion concerns, i.e. operating environments S2 and N2.

Table 9: Level of Service to Operating Environment mapping table

[1] ERTICO 1997. TELTEN2 Final Report. Road Transport Telematics for better traffic management in Europe. CD-ROM. Brussels, March 1997