General Information VG204XM Cisco Analog Voice GatewayManufacturer Cisco Systems, Inc
Manufacturer Website Address http://www.cisco.com
Product Series VG200
Product Model VG204XM
Product Name VG204XM Analog Voice Gateway
Product Type VoIP Gateway
Management Port Yes
Number of Network (RJ-45) Ports 2
Number of FXS (RJ-11) Ports 4
Network & Communication
Ethernet Technology Fast Ethernet
Wireless LAN No
Dimensions and Weight
Height 1.8 lnch
Width 8.8 lnch
Depth 8.1 lnch
Weight 2.98 lbs
Management & Protocols
Voice Codec T.38
Voice Codec G.729a
Voice Codec G.711
The voice over internet protocol gateway essentially acts as a bridge between legacy telephone systems and VoIP solutions by intelligently adapting and routing calls from one medium to another. VoIP is the technology used to make phone calls via the internet rather than through mobile devices or regular landline. A high-speed internet connection is required to support IP telephony. VoIP gateways take analog voice signals and convert them into data packets sent just like digital data over a broadband connection.
The gateway serves to connect traditional phone systems such as ACDs and PBXs with VoIP services or vice versa (connecting VoIP solutions to legacy phone systems). The process of converting voice over IP calls from one code to another is called transcoding. Depending on the VoIP setup, you may be in a position to keep the old phone number.
Normally, gateways will be used to connect to multiple VoIP endpoints such as services and devices to ensure PSTN resources are shared between multiple IP communication systems.
The addition of VoIP networking to legacy phone systems presents the opportunity to add more features and extend the life of legacy equipment. The use of VoIP solutions alongside legacy equipment in a hybrid setup will help in cutting costs and preventing disruption of business processes. The legacy phone system will, therefore, see the gateway as another networked PBX or as the phone service provider. It works as follows: voice signals from phone calls using the PBX are converted into VoIP data and transmitted over the internet using the service provider or VoIP peers. The incoming calls from VoIP are converted into the legacy protocol being used and sent to the PBX.
There are two types of VoIP gateways:
- Analog gateways – used to convert between traditional analog phones and phone lines and VoIP protocols.
- Digital gateways – used to convert between VoIP protocols and different types of digital phone services such as E1, T1, BRI, and PRI.
The biggest benefit of VoIP phones is the cheaper cost of calling compared to landlines especially when calling over a long distance. Some setups are completely free or are bundled together as a package with FTTP connections.
Key features of our VoIP gateways include:
- Compliance with multiple protocols including H.323, MGCP, SCCP, and SIP.
- Automatic provisioning via TFTP/HTTP
- Support for many voice codecs including G.711, G.723.1, G.726, and G.729A.
- Call routing and least-cost call routing capability
- Echo cancellation, Jitter buffering, VAD, and CNG for clarity even on low strength connections.
- T.38 compliance to support faxing.
- Web-based administration/management
VoIP gateways are also used to build redundancy on a system such that the gateway communicates with the primary IP in normal PBX setups. The gateway will communicate with a backup system if there is a failure. The use of a gateway to connect a VoIP system to a traditional phone makes sense if SIP trunks are unavailable or the reliability of a PSTN is needed.
VoIP gateways can also be used for staged migrations by setting it up as a bridge within a legacy PBX setup, the PSTN setup, and the new IP PBX setup. The PSTN setup trunks will be connected to one interface while the second interface will be connected to the legacy PBX trunk port. A VoIP protocol integration is undertaken for the new IP PBX.
The VoIP gateway also offers flexibility by passing calls between two PBXs and becomes useful in allowing some departments within a company to keep using a legacy system as other departments migrate to the VoIP system.We offer a big line of new and refurbished VoIP gateways including wireless, external, 10-100 gateways, and other VoIP solutions from reputable manufacturers that will meet your needs without exceeding your budget.