REDCOM Gateway Overview

Service providers are looking for ways to lower operating expenditures, and increase margins, while consolidating resources and at the same time offering new value-added services to their subscriber base. REDCOM’s next-generation solutions enable service providers to deploy flexible multi-technology networks that can adapt to increasing end-user demands and competitive industry dynamics at a lower operating cost. REDCOM’s next-generation solutions are powerful multi-technology telecommunications systems ideal for public exchange switching including end office, tandem office, media gateway and international gateways

How REDCOM addresses Service Providers’ Media Gateway needs

REDCOM’s gateway solutions, the HDX and SLICE 2100, can be configured as a Softswitch, Emergency Standalone or a Media Gateway. Thanks to the TRANSip® architecture, four core elements (Call Control, Media Gateway, Media Gateway Control and Legacy Support) are fully integrated providing Service Providers the flexibility and the benefits of a fully interoperable network while retaining valuable network assets.  TRANSip incorporates the benefits of TDM and IP technologies, providing a full range of related IP telephony capabilities and features, also supporting traditional TDM transport and signaling interfaces and features. 

REDCOM’s gateway solutions, the HDX and SLICE 2100, converge existing TDM components with IP technologies to gain the maximum benefits of each. These platforms support various signaling protocols including Standard SIP, SS7, C7, ISDN PRI, ISDN BRI, MF/R1, MF/R2, GR-303, TR-08, FXO and V5.2.  Different trunk interfaces including T1, E1, E&M and ring-downs are supported to make convergence practical. These platforms also support T.38 for fax communications over IP and V.150.1 for modem communications over IP. This is critical for customers who still rely on these communications methods. These REDCOM gateway solutions are interoperable with a wide range of remote access solutions including GR-303, V5.2, and Broadband Loop Carriers (BLC), and  can be configured to handle multiple groups and MSANs (Multi-Service Access Network). Connecting to a Digital Loop Carrier or Broadband Loop Carrier remote, REDCOM offers interoperability to advanced technologies, remote operation capability and efficient network management.

Media Gateway Function (MGF) with Built-in IP Compression – Savings & Flexibility

Both the HDX and SLICE 2100 (when equipped with TRANSip) operate as a powerful Media Gateway. These solutions equipped with TRANSip, offer a full range of capabilities that allow Service Providers to address customers’ needs while you counter low-cost competition. Flexible compression methods help you manage bandwidth usage, while retaining critical subscribers with high bandwidth and premium services.

On the VoIP side, many codecs are supported including G.711 A-law, G.711 μ-law, G.723.1H&L, G.726 (16, 24, 32, 40 kb/s), G.729 A&B, iLBC, as well as T.38 for Fax over IP and V.150.1 for Modem over IP. On the TDM and analog side, a wide variety of interfaces are available, including E1, T1, E&M, Ground Start and Loop Start trunks, Magneto, and Radio interfaces with support for many industry standard protocols including ISDN PRI, IDSN BRI, SS7, C7, SS5, DTMF, MF/R1, MF/R2, GR-303 and V5.2.

Breakout Gateway Control Function (BGCF)

Through TRANSip, REDCOM’s gateway solutions perform call routing based on telephone number. Outbound calls can be routed via VoIP to another network / system, or via TDM (using the MGCF functionality). In the traditional TDM world, subscriber access was relatively straightforward. Phones would be wired to a switch at a central location. Compatibility between traditional switching platforms and traditional analog telephones was generally strong, thanks to the maturity of the technology. As traditional telephony systems grew in size, it was realized that offering many lines at a central location could become very expensive. This often involved a significant investment in cable plant and switching hardware. A new technology was developed to aggregate line-side connectivity at a location closer to subscribers, to reduce investment in cabling to subscribers. This new technology (Digital Loop Carrier / DLC or Remote) would handle line-side functionality,  but would still rely upon a central switching platform for call control. Cabling between the DLC / Remote (T1/E1) was significantly reduced compared to individual cable pairs for each subscriber, and could be copper or fiber. GR-303 and V5.2 are examples of industry-standard protocols used to aggregate subscribers on a DLC / Remote, and are both supported by REDCOM’s gateway solutions.


Most manufacturers of gateways provide an array of multiple external boxes thus increasing Operation Expenses by adding training and maintenance cost through mandatory maintenance agreements.

Because all TRANSip-enabled REDCOM Systems are fully integrated, they provide seamless IP to TDM interoperability which is valuable for converged networks. TRANSip is REDCOM's IP telephony technology suite that incorporates the benefits of TDM and IP technologies, providing a SIP Call Controller, Media Gateway, Media Gateway Controller, and a full range of related IP telephony capabilities and features, also supporting traditional TDM transport and signaling interfaces and features. This seamless interoperability helps Service Providers by obtaining efficiencies while consolidating resources in their network. It does not matter the application, whether you need to implement a SIP to GR-303/V5.2 Gateway or a SIP to ISDN PRI Gateway, REDCOM has you covered. REDCOM’s gateway solutions, equipped with TRANSip, are the best Media Gateway solutions solving Service Providers’ Media Gateway needs.

VoIP Capabilities

Supported Codecs

  • G.711µ
  • G.711a
  • G.729 A&B
  • G.726 16, 24, 32 or 40 kbit/s
  • G.723.1 5.3 or 6.3 kbit/s
  • G.723.1A 5.3 or 6.3 kbit/s
  • iLBC 20 or 30ms
  • RFC4040 Clearmode
  • NSA MER No Audio

Fax over IP

  • T.38
  • Pass-through

Modem over IP

  • V.150.1
  • Pass-through

DTMF Relay

  • In band
  • RFC 2833

Other Features

  • Secure RTP (SRTP)
  • RTCP
  • Voice Activity Detection (VAD) with Silence Suppression
  • Comfort Noise Generation
  • Packet Loss Concealment
  • Echo Cancellation (G.165 or G.168 with variable tail coverage) 
  • Configurable packet Rate (per-trunk and per-subscriber) 
  • Jitter Buffer (Dynamic/Adaptive or Fixed) 
  • IPv6 Support for Signaling and Media 
  • Custom SDP Manipulation 
  • Embedded Real-Time Troubleshooting Tools 
  • Custom Bandwidth Budgeting

The HDX and SLICE 2100 support a wide variety of traditional TDM and analog interfaces and protocols, as well as a variety of hard-to find interfaces and protocols (such as radio) to deliver carrier-class media gateway functionality unlike any other.

Supported TDM/Analog Interfaces and Protocols:


  • MF / R1, FG-C&D 
  • DTMF, MFC R2 
  • SS5 / C5 
  • SS7 / C7
  • GR-303 

Basic Rate ISDN

  • BRI-S 
  • BRI-U 


  • 2-wire (multiple types) 
  • 4-wire (multiple types)

Analog Line

  • Loop Start (FXS) 
  • Ground Start (FXS) 
  • Magneto (Local Battery) 
  • Loop Start Ringdown Trunk (FXO) 
  • Ground Start Ringdown Trunk (FXO) 
  • Two-way Loop Trunk (DID trunk) 


  • Vox triggered Push-to-Talk (PTT) 
  • DTMF triggered Push-to-Talk (PTT)
  • BRI triggered Push-to-Talk (PTT) 
  • SIP triggered Push-to-Talk (PTT) * 
  • Carrier Operated Relay (COR)

* REDCOM Patented Technology

Best of all, TRANSip includes REDCOM’s integrated call control capability and lineside functionality all in the same box, so the SLICE 2100 or HDX can operate with or without assistance from an external call controller. In the event of any network outages, the SLICE 2100 or HDX can operate independently, with the ability to allow calling between attached users and trunks. 

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