The soft switch is a central element in the new generation telecommunications the, which connects telephone calls from one line to another on a network or internet connection, also integrates different protocols in the NGN.

Circuit switches are efficient elements in the PSTN structure, although they have never been optimized for data, As the data traffic grows over the Internet on the public network the need for more and more new data access focuses on the design of future switches based on packet technology for more voice and data transmission

The CHAKAVAK switch is one of the most important components of the system, which plays a primary role with third-party subscribers and operators, and therefore has a good performance and scalability. This system only receives signaling and is not in the media path.

  • Registration
  • Routing
  • Authentication
  • Location
  • Presence

features of the soft switch is:

  • Ability to make Voice, Video calls
  • Supports SIP protocol, SIP + H.323, H.248 (Megaco), TLS version 2 for signaling
  • Supports RTP / SRTP / ZRTP for media
  • Simple protocol support for text messages
  • Connect to traditional networks through SS7 / PRI protocols
  • Support for G729 / G723 / GSM / Speex / G711 codecs
  • The ability to convert codecs to Transcoding
  • Connect to the charging system through Diameter Credit Control
  • The ability to process 3000 packs per second on each node
  • The clustering function and the use of several nodes simultaneously
  • Instant Messaging via SIP Simple
  • Connect with SPR and download user profiles
  • Connect with Routing Server for Routing
  • Maintaining customer contact method
  • Keep your physical location together
  • SIP Proxy
  • Web Socket
  • XCAP


The p-cscf is located in the signaling and media paths for the subscribers of each province, providing features such as Transcoding, and NAT Traversal. p-cscf is only involved with subscriber contacts, and because of the media's direction, it has a higher processing pressure than the soft-switch hackock switch. One of the most important tasks of this system is support for Lawful Interception (LI) systems. This system also provides the IRI for both HI2 and CC for HI3 to the LI server. Another important task of this system is to handle the call accounting and communication with the OCS through the Diameter protocol.


  • Media Relay
  • Transcoding
  • NAT Traversal
  • IPv4 to IPv6 tunneling
  • DTMF Relay
  • System Announcements


  • ۲,۰۰۰ concurrent calls per node
  • Clustering and increasing capacity by adding nodes
  • Generate CDR format in CSV format
  • Supports Diameter Credit Control
  • Support for G.711 codecs (a-law, μ-law), G.729 (A / B), G.723.1, G.726 (32 kbps), GSM, ILBC
  • Ability to playback the reason for not calling and credit existing or used
  • Supports STUN, ICE


According to RFC3525 and the MGCP protocol, performs as calls signaling and conference management .This system, in conjunction with Media Gateways, enables communication between Circuit Switched Systems and Packet Switched Systems. Set up, manage, and disconnect the Media Gateway calls through this system