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Quintum Tenor ASM200

  • Editors' rating
    8.5 Excellent


  • Port mapping makes for easy deployment
  • good call quality
  • automatic failover and intelligent call routing facilities
  • PacketSaver technology for bandwidth optimisation


  • No browser-based management

US-based Quintum Technologies sells a range of VoIP switches based on its own Multi-Path technology which, it claims, offers superior performance, quality and availability compared to alternative solutions. Its principal product family, the Tenor, is available both through resellers and from Nortel Networks as part of the Nortel Communication Server 1000 IP telephony solution.

With a choice of either analogue or ISDN digital interfaces, the Tenor family includes switches capable of handling up 120 calls at a time. However, for our tests we concentrated on the 2-port Tenor ASM200, which is designed both for small business use and in support of branch office telephony.

The hardware itself is compact and robust, with two FXO ports for attachment to PBX extensions or external phone lines and two FXS ports for analogue phone connection. LAN connectivity is via a 10/100Mbps Ethernet interface and there’s a serial port to assign an IP address to the unit via a local terminal. You can also, if you want, configure and manage the Tenor via the serial interface, but most users will prefer the Java-based Tenor Configuration Manager that can be run remotely on any networked PC.

There’s a lot you can do with the Tenor, including linking PBX systems together via VoIP with remote breakout to the PSTN for least-cost routing and local failover in the event of network/power failure. However, we were only interested in long line extension: to this end, Quintum supplied two switches, one of which we attached to our PBX in the lab while the other was located at a remote office and had analogue phones attached.

In this configuration the Tenor gateways proved very easy to deploy, with a straightforward facility to map the ports on one gateway to those on the other. It took only a few minutes to configure our test setup, and once complete the remote VoIP handsets were almost indistinguishable from local extensions. Call quality was excellent and we were able to put calls on hold and transfer them as normal. We also liked the way the Quintum gateways were able to intelligently route calls with minimal setup on our part.

If you prefer, other gateways and IP phones can be used with the ASM200 thanks to its support for both H.323 and SIP signalling. However, setup would then be a lot harder. The documentation could also benefit from some attention, but other than that we had few issues with the Quintum Tenor ASM200, which performed extremely well with minimal fuss.