Despite　the　widespread　use　of　radio　frequency　identification　and　wireless　connectivity　such　as　near　field　communication　in　electric　vehicles,　their　security　and　privacy　implications　in　Ad-Hoc　networks　have　not　been　well　explored.　This　article　provides　a　data　protection　assessment　of　radio　frequency　electronic　system　in　the　tire　pressure　monitoring　system　(TPMS).　It　is　demonstrated　that　eavesdropping　is　completely　feasible　from　a　passing　car,　at　an　approximate　distance　up　to　50　m.　Furthermore,　our　reverse　analysis　shows　that　the　static　n-bit　signatures　and　messaging　can　be　eavesdropped　from　a　relatively　far　distance,　raising　privacy　concerns　as　a　vehicles＇　movements　can　be　tracked　by　using　the　unique　IDs　of　tire　pressure　sensors.　Unfortunately,　current　protocols　do　not　use　authentication,　and　automobile　technologies　hardly　follow　routine　message　confirmation　so　sensor　messages　may　be　spoofed　remotely.　To　improve　the　security　of　TPMS,　we　suggest　a　novel　ultralightweight　mutual　authentication　for　the　TPMS　registry　process　in　the　automotive　network.　Our　experimental　results　confirm　the　effectiveness　and　security　of　the　proposed　method　in　TPMS.　©　2005-2012　IEEE.