Legacy PBX and PSTN Connectivity

Enterprise Media Gateways: Connecting UC to a PBX or the PSTN

Unified Communications (UC) is an important trend in converged TDM-IP enterprise communications for businesses that want to remain competitive. UC integrates disparate communication elements that employees use every day to deliver significant productivity gains. Among these elements are presence, instant messaging, voice, voice messaging, email, fax, conferencing, and web collaboration. These elements are accessed from a variety of endpoints, client softphones, hard phones, and mobile devices, and are combined in a convenient desktop interface as well as a separate mobile voice user interface, and may also be embedded in business applications. The goal of UC is to improve access and control over user communications, as well as to speed up the business process overall.

Media gateways can provide a standard interface and a bridge between IP-network-based UC solutions, such as the Microsoft® Lync Server and legacy PBX and PSTN networks. The illustration on this page provides an example of a converged UC environment. 

Converged UC Environment

Converged UC Environment 

Enterprise Media Gateways, such as the Dialogic® Media Gateway (DMG Gateway) shown in the drawing on this page, smooth the transition to IP networks and IP-based applications like UC, while leveraging an organization’s investment in existing equipment, such as a PBX, by allowing it to continue to be used while employees with UC become more productive and efficient. Options such as direct PSTN or SIP trunk connectivity can also supplement or replace PBX public network connectivity.

Key Features of Dialogic® Media Gateways (DMG Gateways)

  • Focus on CPE-based applications such as UC
  • Provide 4 to 120 channels of VoIP and FoIP connectivity per gateway
  • Enable “any-to-any” signaling: TDM-to-SIP, SIP-to-SIP, TDM-to-TDM
  • Have been successfully tested for interoperability with leading legacy PBX switches
  • Allow turnkey appliance ease-of-use and support for third-party SIP and FoIP applications
  • Support up to V.34 fax transmission speeds over T.38 FoIP

Learn More about Dialogic® Media Gateways

Two series of Dialogic® Media Gateways are available for this function:

Dialogic® 1000 Media Gateway Series (DMG1000 Gateways)

Connected between a PBX or a digital handset and a LAN or WAN, Dialogic® 1000 Media Gateways converts proprietary digital PBX messages into a format suitable for transmission over standard IP networks. DMG1000 Gateways can handle 4 to 8 sessions per gateway with analog or digital PBX-to-SIP and T.38 FoIP signaling and transport. For more details about this gateway, go to its product page.

Dialogic® 2000 Media Gateway Series (DMG2000 Gateways)

Dialogic® 2000 Media Gateways provide an interconnect between legacy PBXs and various IP endpoints. DMG2000 Gateways handle 24 to 120 sessions with TDM-to-SIP, SIP-to-SIP, TDM-to-TDM, and T.38 FoIP signaling and transport. For more details about this gateway, go to its product page.

Dialogic® 4000 Media Gateway Series (DMG4000 Gateways)

The Dialogic® 4000 Media Gateways (DMG4000 Gateways) are integrated systems that can provide both local PSTN and voice endpoint connectivity at a branch office premise as well as base-level voice service continuity in the event that the corporate WAN becomes unavailable. For more details about this gateway, go to its product page.

See also the Dialogic® BorderNet™ 500 Gateway.

More Information

You may find the following useful:

Catapult Systems Projects $250,000 in Savings from Move to VoIP and Unified Communications

Choosing a Media Gateway Appliance

Estimating Trunk Channel Requirements for VoIP Gateways in Unified Communications Deployments