- Supported features and standards

Last modified by Elisa Nectoux on 2024/10/06 18:19

Flexisip has the following main features:

PROXY

  • Transport protocols: SIP/UDP, SIP/TCP and SIP/TLS
  • Digest and TLS client certificate authentication
  • Routing based on a registrar database or static route file, with forking
  • Interconnected with push notifications systems for reliably notifying mobile apps of incoming calls or messages (including​support of RFC8599 for the transmission of the push notification information through REGISTER requests, where we leverage to adapt to iOS 13 new push notification constraints)
  • « Store and forward" logic for SIP MESSAGE (IM) so that text messages can be delivered when the recipient connects to the network
  • NAT-aware with a built-in media relay module and ICE/STUN support for high level event logging for activity monitoring
  • Real-time statistics available through a command line interface
  • High availability and cluster mode for large deployments
  • ExternalAuthentication, a proxy module that performs SIP request authentication based on the inputs of an external http service. It typically allows Flexisip to interact with a third party authentication service in order to authenticate a SIP request.

PRESENCE

Flexisip manages SIP SUBSCRIBE and PUBLISH from client applications, in order to

  • Identify users of the service within the address book
  • Provide users with real-time presence status

Flexisip presence server also offers a “Server known resource lists” feature, that allows to directly provision a Liblinphone-based client with a server defined contact list, together with associated presence information. The typical use case can be to have team workers sharing a common company-defined address book on their communication app.

CONFERENCE (for group messaging and group calling)

  • Entirely SIP-based solution
  • Efficient management of groups and participants
  • Multi-device support
  • Notifications of group events (users joining or leaving, new admins etc.)

Flexisip conference server can also be integrated into an existing third party server (for more details, see our wiki).

Implemented standards

PROXY

  • SIP, RFC 3261
  • An Extension to the Session Initiation Protocol (SIP), RFC 3581 (use of rport parameter)
  • A Session Initiation Protocol (SIP) Event Package for Registrations, RFC 3680
  • Extension Header Field for Registering Non-Adjacent Contacts, RFC3327
  • Managing Client-Initiated Connections in the Session Initiation Protocol (+sip.instance parameter), RFC 5626
  • Connection reuse in the Session Initiation Protocol (alias parameter), RFC 5923
  • GRUUs; RFC 5627
  • Push Notification with the Session Initiation Protocol (SIP), RFC 8599

PRESENCE & CONFERENCE

  • Session Initiation Protocol (SIP) - Specific Event Notification, RFC 6665
  • Session Initiation Protocol (SIP) Extension for Event State Publication, RFC 3903
  • A Presence Event Package for the Session Initiation Protocol (SIP), RFC 3856
  • A Data Model for Presence, RFC 4479
  • RPID: Rich Presence Extensions to the Presence Information Data Format (PIDF), RFC 4480
  • Subscriptions to Request-Contained Resource Lists in the Session Initiation Protocol (SIP), RFC 5367
  • Conference Establishment Using Request-Contained Lists in SIP, RFC 5366
  • SIP body compression, RFC 1951
  • Message Body Handling in the Session Initiation Protocol, RFC 5621
  • SIP Event Package for Conference State, RFC 4575