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Send voice and data over one pipe—and cut voice costs down to size. That’s the promise of Integrated Voice and Data service (iVAD) from Equant Network Services. The carrier says its voice-over-frame offering saves an average of 20 percent to 40 percent over circuit-switched voice, depending on location and volume. What’s more, Equant’s service keeps voice at toll quality using queuing, echo cancellation, and silence suppression. And it’s fully managed, easy to set up, and available in more than 40 countries.
Drawbacks? Potential customers will need to study network traffic patterns to determine how much bandwidth they’ll need. The service has no standard service-level agreements (SLAs). And customers will need a separate circuit to send mission-critical data, which cuts back the savings.
Cheaper Choice
Still, Equant (Atlanta) says voice over frame is much cheaper than a separate data and voice network. Exactly how much cheaper? That depends on premises router costs, local-loop charges, port speed, and geographic location. Equant says a line with a 32-kbit/s CIR (committed information rate) between France and Germany goes for 25 cents per minute, including the router. That’s 15 percent less than the circuit-switched rate of 29 cents per minute. A comparable pipe between Hong Kong and Brazil is even cheaper. Here, Equant’s rate is 55 cents per minute, 73 percent less than the $2 circuit-switched rate.
The carrier has also taken several steps to ensure voice is toll quality. First, Equant’s queuing scheme prioritizes voice over data, so voice calls will always get the bandwidth they need. Second, the carrier says it doesn’t oversubscribe its network, so customers won’t see voice degradation or data loss due to congestion. Third, it uses gear from Cisco Systems Inc. (San Jose, Calif.) that features echo cancellation and silence suppression.
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Voice Gets Framed
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And Equant also takes the pain out of setup and management. The service relies on a single Cisco 3810 router that Equant installs, configures, upgrades, and maintains (see the figure). The 3810 connects to frame relay lines at up to T1 (1.544-Mbit/s) or E1 (2.048-Mbit/s) speeds and handles both analog and digital telephony interfaces—up to 24 compressed digital voice channels and six analog voice channels. It also connects to the LAN via an Ethernet interface. Customers set the CIR of their frame relay PVCs (permanent virtual circuits) based on the volume of their data traffic and expected volume of voice calls.
Global Reach
Companies looking to connect offices in faraway places will like Equant’s global reach. It offers iVAD in 40 countries around the world. That’s more than Infonet Services Corp. (El Segundo, Calif.), its closest voice-over-frame competitor, whose service reaches about 30 countries. Equant hopes to expand iVAD to more regions, as regulators remove restrictions on voice services.
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Product Summary
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Still, there are downsides. Setting the CIR is no easy task—and any frames transmitted beyond the CIR are eligible for discard, depending on network congestion. And though Equant offers to help corporate networkers do the CIR math, they’ll still need to figure out times of peak voice and data usage and allow enough bandwidth for both to travel at once. As a rule of thumb, the carrier says that every compressed voice connection requires 8 to 11 kbit/s, plus 3 kbit/s of frame relay overhead.
What’s more, since Equant’s service sends voice first, customers who want to ensure bandwidth for their mission-critical or real-time data applications will need to provision separate voice and data PVCs—adding to the cost of the service.
Network managers looking for a standard SLA will also be disappointed. Right now, Equant’s guarantees are on a per-case basis, depending on geography. Customers can negotiate parameters such as network availability, whether or not iVAD will block voice calls if no bandwidth is available, and network delay. The carrier says it’s working on a standard SLA for voice quality based on the Mean Opinion Score of the ITU (International Telecommunication Union), a four-point rating scale, where a four indicates toll-quality voice.
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