H.248

Also known as Megaco, H.248 is a protocol for controlling media gateways via a softswitch or a media gateway controller.

TelcoBridges and H.248

Toolpack now supports the H.248 protocol.

As indicated in the diagram below, the H.248 stack is a module in the media gateway application residing on the application server. It communicates with the various Toolpack classes (CAFClass, CMC Library, CMC Class) as required via a new Media Leg API. In turn, the media gateway application communicates with the softswitch / media gateway controller via the H.248 protocol.

H.248 package support

Toolpack supports the following packages.

• H.248.1
  • Protocol v2
  • IPSec connection support
  • Support UDP (2944 or user-defined)

• H.248.1 - Basic packages
  • Generic
  • Base Root
  • Tone generator (for extension purposes only)
  • Tone detection (for extension purposes only)
  • Basic DTMF generation
  • DTMF detection
  • Call Progress Tones Generator
  • Basic continuity package
  • Network package
  • RTP package
  • TDM Circuit package

• H.248.2 Facsimile, text conversation and call discrimination packages
  • Fax/TextPhone/Modem tones detection (fax and data only)
  • Call type discrimination package (fax and data only)
  • IP Fax (Event: Fax Connection Change - end of fax session, call terminating)

• H.248.4 Transport over Stream Control Transmission Protocol (SCTP)

• H.248.7 Generic announcement package
  • Generic announcement package

• H.248.10 Media gateway resource congestion handling package
  • Congestion handling package

• H.248.11 Media gateway overload control package
  • Overload control package

• H.248.13 Quality alert ceasing package
  • Quality alert ceasing package

• H.248.14 Inactivity timer package
  • Inactivity timer package

Additional details

• Support for text mode only
• Not supported on Solaris builds

References

• Wikipedia article