C-ITS with V2X SCMS

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• C-ITS

  • What is C-ITS?
  • Threats in the V2X communication environment

• V2X SCMS

  • What is SCMS?
  • Types and functions of certificates
  • The role of agency

• Certificate-based communication

  • Signing and verification
  • Communication process

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C-ITS (Cooperative Intelligent Transport Systems)

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1. What is C-ITS?

• Vehicles and road infrastructure exchange traffic information in real time through two-way communication.
• Improved road safety and mobility
• Providing safety services through ‘V2X communication’
  • Provides location-based traffic information
  • Emergency vehicle approach warning
  • Providing road danger section information

V2X(Vehicle to Everything) Communication: vehicle <-> vehicle, infrastructure, pedestrian

2. Threats in the V2X communication environment

• Information sharing between various devices participating in communication

• Possible security threat is as follows.
  ex) Hacking, Information leakage, etc.

• Requirement for reliability of information and anonymity of users
  => Requires a safe and secure communication environment!
  
  
  
  

V2X SCMS (V2X Security Credential Management System)

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1. What is SCMS?

• Public key-based authentication system
• Provides management functions for certificates of vehicles and infrastructure

2. Types and functions of certificates

• Enrollment Certificate

  • For Credentials Certificate
  • Used when requesting Pseudonym/Identification/Application Certificates
  • ex) Vehicles, Infrastructure

• Pseudonym Certificate

  • privacy protection of vehicles
  • ex) Normal vehicles except public vehicles

• Identification Certificate

  • Identity of vehicles that do not require privacy
  • ex) Ambulance, Police Car, Fire Truck, etc.

• Application Certificate

  • collect and provide of traffic information
  • ex) Road Infrastructure

3. The role of agency

• ECA (Enrollment CA)

  • Issuance and management of certificates for V2X communication devices
  • Ex) Enrollment Certificate

• PCA (Pseudonym CA)

  • Issuance and management of certificates required for secure communication of devices
  • Certificate issuance is performed at the request of the RA.
  • Ex) Pseudonym Certificate, Identification Certificate, Application Certificate

• RA (Registration Authority)

  • Acts as a relay so that the device can access the authentication system
  • Provide services for issuing certificates for devices linked to PCA
  • Support MA's certificate revocation work
  • Ex) Pseudonym Certificate, Identification Certificate, Application Certificate

• LOP (Location Obscurer Proxy)

  • In response to a request for issuance of an pseudonym certificate, information that could be used for vehicle location information is removed and forwarded to the RA

• MA (Misbehavior Authority)

  • Abnormal behavior verification agency
  • Determination of abnormal behavior based on abnormal behavior report transmitted from V2X communication device
  • Revocation of certificates for anomalous devices
    
    
    
    

Certificate-based communication

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1. Signing and Verification

• Store own public and private key pairs

  • The public key is stored in own certificate.

• Sender

  • Data' = Hash(Date)
  • Generate a signature for Data’ using sender's private key
  • Send the Data, Signature, Certificate

• Recipient

  • Data'' = Hash(Data)
  • Obtain Data’ from the Signature using the sender’s public key in received Certificate
  • Check Data' == Data''

⇒ User Authentication, Message Integrity Verification

user authentication: verify that the message comes from the person I am communicating with

message integrity: ensure that the message has not been forged or altered in the middle.

2. Communication Process

• Issuance of a appropriate certificate for the situation from a certification authority through a enrollment certificate
  • Generate a signature for the message then perform communication with certificate

• Extract the sender's public key from the Certificate
• Verify the Signature for the Message with the corresponding public key

  ⇒ Provides a secure communication environment

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