Introduction to certificates

Hypertext Transfer Protocol Secure (HTTPS) est une extension de Hypertext Transfer Protocol (HTTP) pour une communication sécurisée sur un réseau informatique. Sur HTTPS, le protocole de communication est crypté en utilisant Sécurité de la couche transport (TLS), ou son prédécesseur, Couche de sockets sécurisés (SSL).

Dans XProtect VMS, la communication sécurisée est obtenue en utilisant TLS/SSL avec un chiffrement asymétrique (RSA).

TLS/SSL utilise une paire de clés (une privée, une publique) pour authentifier, sécuriser et gérer les connexions sécurisées.

Une autorité de certification (AC) est toute personne capable d'émettre des certificats racine. Il peut s'agir d'un service Internet qui émet des certificats racine ou de toute personne qui génère manuellement et distribue un certificat. Une AC peut émettre des certificats aux services Web, c'est-à-dire à tout logiciel utilisant la communication https. Ce certificat contient deux clés, une clé privée et une clé publique. La clé publique est installée sur les clients d'un service Web (clients de service) en installant un certificat public. La clé privée est utilisée pour la signature des certificats de serveur qui doivent être installés sur le serveur. Lorsqu'un client de service appelle le service Web, le service Web envoie le certificat du serveur incluant la clé publique au client. Le client de service peut valider le certificat de serveur utilisant le certificat public de l'AC déjà installé. Le client et le serveur peuvent maintenant utiliser les certificats de serveur publics et privés pour échanger une clé secrète et par conséquent, établir une connexion TLS/SSL sécurisée.

Pour les certificats distribués manuellement, les certificats doivent être installés avant que le client ne puisse effectuer cette vérification.

Reportez-vous à la section Transport Layer Security pour plus d’informations concernant TLS.

In XProtect VMS, the following locations are where you can enable TLS/SSL encryption:

  • In the communication between the management server and the recording servers, event servers, and mobile servers
  • On the recording server in the communication with clients, servers, and integrations that retrieve data streams from the recording server
  • In the communication between clients and the mobile server

In this guide, the following are referred to as clients:

  • XProtect Smart Client
  • Management Client
  • Management Server (for System Monitor and for images and AVI video clips in email notifications)
  • XProtect Mobile Server
  • XProtect Event Server
  • XProtect LPR
  • Milestone Open Network Bridge
  • XProtect DLNA Server
  • Sites that retrieve data streams from the recording server through Milestone Interconnect
  • Third-party MIP SDK integrations that support HTTPS
  • For solutions built with MIP SDK 2018 R3 or earlier that access recording servers:
    • If the integrations are made using MIP SDK libraries, they need to be rebuilt with MIP SDK 2019 R1
    • If the integrations communicate directly with the Recording Server APIs without using MIP SDK libraries, the integrators must add HTTPS support themselves
    • If in doubt, ask your vendor who supplied the integration

    • Certificate distribution

    The graphic illustrates the basic concept of how certificates are signed, trusted, and distributed in XProtect VMS.

    A certificate authority (CA) is anyone who can issue root certificates. A CA certificate acts as a trusted third-party, trusted by both the subject/owner (server) and by the party that verifies the certificate (clients) (see Create CA certificate).

    The public certificate must be trusted on all client computers. In this way the clients can verify the validity of the certificates issued by the CA (see Install certificates on the clients).

    The CA certificate is used to issue private server authentication certificates to the servers (see Create SSL certificate).

    The created private SSL certificates must be imported to the Windows Certificate Store on all servers (see Import SSL certificate).

    Requirements for the private SSL certificate:

    • Issued to the server so that the server's host name is included in the certificate, either as subject (owner) or in the list of DNS names that the certificate is issued to
    • Trusted on all computers running services or applications that communicate with the service on the servers, by trusting the CA certificate that was used to issue the SSL certificate
    • The service account that runs the server must have access to the private key of the certificate on the server.

    Certificates have an expiry date. You will not receive a warning when a certificate is about to expire. If a certificate expires, the clients will no longer trust the server with the expired certificate and thus cannot communicate with it.
    To renew the certificates, follow the steps in this guide as you did when you created certificates.