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1 #!" # $%#"$!&###'# (")*+,-.)*+,/#0 (" (# 1"*% :#, 1"#2 3( 1# 1"#41(,(# 5" (6(,( 1#, 3(# 2$#7/#( 8 96"5" &9: (.)# 5(( 8 ;<&9: P@N communications could be deployed across some or all of the HA network, but the system requires further trialling before a final decision is made. On paper it appears that it can support low bandwidth tools, such as VMS, but it is expected that a trial would support the theory that it cannot sustain high bandwidth applications, such as CCTV. Each case of connection from a P@N aggregator to the main communications network, whether it be hard-wired or GPRS, will need to be analysed on its own merits. Despite the anticipated low cost (relatively) of a P@N network, the added expense of connecting aggregators may prove too great. As a result, P@N could provide an extension to the HA communications network for low bandwidth applications, but not necessarily in every situation. With regards to the ERHWS project, it might appear appropriate to utilise P@N as an enabler for any trial, where communications back to a controller is required but is not otherwise available. However, any failure of what is currently an untried system would jeopardise the trial. The relative ease and cost of deploying and operating P@N, compared with NMCS2 could be assessed, as part of an incremental study of enhancing the normal system set-up for the trialled Hazard Warning System. Once proven at the trial site, P@N could, potentially, be used for future trials of ITS technologies requiring relatively low bandwidth communications. This should enable trials to be undertaken quicker and, at the same time, provide further proving grounds for the P@N concept itself, prior to any wider deployment of P@N and, thereafter, development and deployment of associated services w. e. itsradar@fabermaunsell.com t f

2 1#((=# "$!&###>?'%## 1 "##"%9" ##%##*:%@ 5#"#% ".##)*+,-.)*+,0 #%###.)*+,/#!!" Concept The P@N system, produced by Visual Innovations (Vi), has, as its main component, a wireless communications infrastructure. In principle, this infrastructure could be deployed across part, or all of the Highways Agency (HA) network. As envisaged by the system designers, it offers accurate location information of vehicles stopping on the hard shoulder. The driver of the stranded vehicle would be required to activate a response mechanism using an electronic keyfob which the vehicle, or driver, would posses. Conceptually, the P@N system provides a low power, wireless mesh network which would enable, amongst other things, the fast and accurate location of vehicles when connected to the network. Assuming that a vehicle is fitted with or is carrying a personal wireless locator (keyfob), the technology is designed to locate the vehicle position in relation to the wireless nodes on the side of the carriageway. The deployed system would be made up of self powered wireless nodes (routers) positioned every 100m on both carriageways and data collectors (aggregators) located every 10km on both carriageways. There are no security issues with P@N because it is protected by 128bit Advanced Encryption Standard (AES 1 ) block cipher. Following a breakdown, the keyfob, when activated, would send a signal to the closest router. The information would then be relayed along the routers to the nearest aggregator. The aggregator would be connected to the National Roads Telecommunications Service (NRTS) or GPRS network which could alert the necessary authorities of the obstruction. #$!! Extension of Communications Network The Highways Agency currently has a telecommunications network alongside the majority of motorways in England. The National Roads Telecommunications Service (NRTS) project aims to upgrade this to a fibre optic network. P@N could be used to support the functions performed by this network. Providing fibre optic cabling alongside all roads within the Highways Agency remit is likely to be prohibitively expensive and just justified in costs benefit terms; P@N potentially provides a low cost alternative. Rather than flanking all roads with fibre optic cable, P@N would entail a small piece of hardware being attached to the already installed marker posts, every 100m, along the length of the road, thus greatly reducing costs. The reduced cost of P@N, compared to a complete wired system, provides the possibility to increase the length of highway covered by NRTS. Highway otherwise excluded from the telecommunications network could have the opportunity to benefit from tools provided to wired sections of the road network. P@N should be able to support low bandwidth tools, such as: 1 As of 2006 AES has not been successfully attacked through cryptanalysis w. e. itsradar@fabermaunsell.com t f

3 Variable message signs (VMS), mobile VMS and matrix signals Real time traffic information (speed and flow data) Lighting control Fog detection Any or all of these tools could be employed on stretches of highway covered by a P@N mesh network without the need for consistent coverage by NRTS. The addition of any new hardware to a P@N network, rather than a wired network, should be cheaper because there is no need for a physical connection between the device and the network. The same applies to the erection of mobile VMS. They will require a form of communication and therefore, although only on a temporary basis, provide the same challenges as the addition of new hardware. The upkeep of embedded traffic sensors used to produce real time traffic information should also be easier within a P@N system, compared to a wired system, because they can communicate with the system wirelessly. As a result, repair and replacement should involve less disruption to network operations because it would be quicker and, consequently, cheaper to carry out the necessary works. A P@N communications system should prove to be no more vulnerable than a wired system. When it comes to accidental damage, a router on a motorway marker is more exposed, but this is balanced by the fact that there is no physical connection between each router that could be broken. Malicious damage is unlikely due to the category of roads on which the system would be deployed; only a determined vandal would stray onto a motorway to cause damage. Limitations P@N provides data communications at a bandwidth of 250kbps; this may not be enough to handle Closed Circuit Television (CCTV) cameras or emergency telephones. This bandwidth may not be able to offer an adequate frame rate for CCTV in this situation. Similarly, the audio clarity afforded by the given bandwidth may also be insufficient for the provision of emergency telephones. The bandwidth provided by P@N may be further reduced by interference from other neighbouring networks. This is unlikely to impact on low bandwidth applications, but means it is even less likely to be able to handle high bandwidth applications. P@N appears to be a low cost alternative to a fully wired network, but its economic advantage may be reduced because it requires some form of connection to a wired network at each aggregator, every ten kilometres. The system designers have suggested that this connection to the network could be in the form of hard-wiring or possibly GPRS. GPRS provides a bandwidth of no more than 150kbps; therefore if this were to be the form of connection then this would further reduce the available bandwidth from the 250kbps provided by P@N. If aggregators were connected to the network through hard wiring then this would incur the cost of connecting them to an existing point from which the data could be transferred to the network. % Traffic officers and/or police incident alert & location system Vi has suggested that P@N could be extended to provide a system for the Highways Agency, and maybe the Police, to provide instant incident location alerts. Rather than just sending data to a breakdown recovery service when a keyfob is activated to indicate a driver is in a stranded vehicle, the information could be forwarded to the nearest Highways Agency Traffic Officer and police vehicles automatically. Hardware could be installed in the vehicles that will provide the officers with accurate information concerning the location of the stranded vehicle. There would be undoubted benefits in the early location of stranded vehicles, particularly those that have been involved in accidents resulting personal injuries. This allows the incident to be cleared as soon as possible, reducing congestion and the likelihood of secondary incidents and increasing survivability of those injured. In this respect P@N is closely allied to an enabling technology for the E-call service being deployed in some parts of Europe. w. e. itsradar@fabermaunsell.com t f

4 Functionality and Services Envisaged as Part of the Road Traffic Advisor (RTA) project - Roadside to vehicle communication P@N could be used to provide some of the functions proposed as part of the (now defunct) Road Traffic Advisor (RTA) system. These functions include, for those drivers with appropriate in-vehicle systems: Information from upcoming static, variable and matrix message signs Advice on traffic conditions Average speed Traffic flow Advance warning of incidents Advice on Weather conditions Visibility Precipitation level Estimated travel times Speed advice (e.g. current speed limit when on a stretch of controlled motorway) Conceptually, such information could be transmitted over the wireless P@N network and be received by a system installed in any vehicle. Such a device, which would appear similar to current satellite navigation systems, might conceivably be adopted by HA Traffic Officers and the Police to provide them with further information and assist them in their on-road activities. In all circumstances, investment would be required to collect, process, collate and make available the information to be distributed via P@N. This could conceivably be an RCC function, but is not a current requirement. Monitoring of fleet vehicle activity Vi, the designers of P@N Communications, suggest that it could be used for monitoring fleet vehicle activity. Vehicle location and status information could be received by the nearest node and transmitted through the network to the fleet company. This function may be limited by the bandwidth offered by P@N, depending on the depth of information required and the number of companies attempting to use it. Priority could be given, in particular, to monitoring the activity of vehicles in the fleet of Highways Agency Traffic Officers or, say, abnormal loads and vehicles transporting hazardous goods. Vehicle tracking A similar system to that used for monitoring fleet vehicle activity could also utilise the P@N system to provide a method of vehicle tracking and consequently stolen vehicle recovery. A stolen vehicle fitted with a P@N transmitter could be located wherever it may be within the P@N network, assuming the transmitter is active whilst the vehicle is in motion. Road toll data P@N will have the ability to track a suitably equipped vehicle wherever it may be within the P@N network. This information could be used to calculate road tolls. It may even have the capability to determine which lane a vehicle is in, providing the option of lane-variable tolling. Electronic Roadside Hazard Warning System (ERHWS) The objective of the ERHWS project is to reduce secondary incidents and prevent further flow breakdown by alerting drivers to hazards. COMPANION is such a system. It currently employs short range communications to detect flow breakdown and potentially provide enhanced information to motorists. P@N, as it stands, could not be used as an ERHWS, but its wireless mesh network component could be combined with COMPANION to provide an enhanced communications component. This proposal is w. e. itsradar@fabermaunsell.com t f

5 covered in the document Assessment of Network Communications for Hazard Warning, produced as part of the ERHWS project. Pilot Schemes 1"%-= 1 '((!! P@N communications could be deployed across some or all of the HA network, but the system requires further trialling before a final decision is made. On paper it appears that it can support low bandwidth tools, such as VMS, but it is expected that a trial would support the theory that it cannot sustain high bandwidth applications, such as CCTV. Each case of connection from a P@N aggregator to the main communications network, whether it be hard-wired or GPRS, will need to be analysed on its own merits. Despite the anticipated low cost (relatively) of a P@N network, the added expense of connecting aggregators may prove too great. As a result, P@N could provide an extension to the HA communications network for low bandwidth applications, but not necessarily in every situation. If P@N was deployed then equipment might then be made available for Traffic Officers and the Police to use the system to accurately locate stranded vehicles. A decision would need to be made whether information is provided through in-vehicle equipment or relayed to vehicles via a control centre. Ubiquitous vehicle to roadside communication does not appear to be a viable option. It is a relatively cheap extension to provide, but the end user cost, to account for the investment required to collect, process, collate and transmit packaged information would be too high. The options of monitoring fleet vehicle activity, vehicle tracking and road toll data are not recommended because, although they would be cheaper than the GPS alternative, they would be restricted to the coverage of the P@N network and, therefore, only a limited number of roads. Regarding the ERHWS Trial With regards to the ERHWS project, it might appear appropriate to utilise P@N as an enabler for any trial, where communications back to a controller is required but is not otherwise available. However, any failure of what is currently an untried system would jeopardise the trial. A staged approach would see a system, such as COMPANION, and its associated communications technology, trialled as a single entity, with alternative communication approaches, such as P@N, substituted in due course. This is particularly relevant for the ERHWS project, as the trial site would potentially be in an area where MIDAS would otherwise be deployed, but is not currently in operation. This would enable the Hazard Warning System to be compared with the alternative of deploying MIDAS, whose costs and benefits are well established. The relative ease and cost of deploying and operating P@N, compared with NMCS2 could then be assessed, as part of an incremental study of enhancing the normal system set-up for the trialled Hazard Warning System. Once proven at the trial site, P@N could, potentially, be used for future trials of ITS technologies requiring relatively low bandwidth communications. This should enable trials to be undertaken quicker and, at the same time, provide further proving grounds for the P@N concept itself, prior to any wider deployment of P@N and, thereafter, development and deployment of associated services. w. e. itsradar@fabermaunsell.com t f