In this paper, we propose a road-to-vehicle communication system with relaxed anonymity via group signatures with time-token dependent linking (GS-TDL). Briefly, a vehicle is unlinkable unless it generates multiple signatures at the same time period. We provide our experimental results (using the RELIC library on a cheap and constrained computational power device, Raspberry Pi), and simulate our system by using a traffic simulator (PTV), a radio wave propagation analysis tool (RapLab), and a network simulator (QualNet). Though a similar functionality of time-token dependent linking was proposed by Wu, Domingo-Ferrer and González-Nicolás (IEEE T. Vehicular Technology 2010), we can show an attack against the scheme where anyone can forge a valid group signature without using a secret key. In contrast, our GS-TDL scheme is provably secure.
In addition to time-dependent linking property, our GS-TDL scheme supports verifier-local revocation (VLR), where a signer (vehicle) is not involved in the revocation procedure. It is particularly worth noting that no secret key or certificate of a signer (vehicle) needs to be updated whereas Security Credential Management System (SCMS) needs to update certificates frequently for vehicle privacy. Moreover, our technique maintains constant signing and verification costs by using the linkable part of signatures. These appear to be related to independent interests.Category / Keywords: cryptographic protocols / Original Publication (with major differences): LightSec 2015 Date: received 10 Nov 2014, last revised 6 Jul 2016 Contact author: k-emura at nict go jp Available format(s): PDF | BibTeX Citation Note: In the conference version (LightSec 2015), we provided the GS-TDL part, and gave experimental results using the TEPLA library (on a cheap and constrained computational power device, Raspberry Pi). In this version, we use the RELIC library and reconsider the pairing equations in our algorithm. Moreover, we simulate our system using a traffic simulator (PTV), a radio wave propagation analysis tool (RapLab), and a network simulator (QualNet). Version: 20160706:080537 (All versions of this report) Short URL: ia.cr/2014/926 Discussion forum: Show discussion | Start new discussion