Silver Networks Q Box Ensures VoIP QoS Over ADSL

By Khali Henderson

Silver Networks Communications announced Wednesday the launch of Q Box, an appliance its maker said will guarantee voice quality for the companys bandwidth-neutral hosted VoIP services delivered over less expensive, lower bandwidth connections, such as ADSL, cable modem or WiMAX.

According to the company, Q Box will enable a hosted VoIP services in location where it would previously have been uneconomical or where voice quality would have been compromised, such as  a SOHO or branch office deployments.  Hosted VoIP service providers typically recommend customers use more expensive SDSL or leased lines for higher capacity connectivity, the company explained in a press statement.

More than 18 months is development, Q Box implements Quality of Service (QoS) controls differently from traditional methods. Voice traffic is no longer treated as data that happens to have a high priority. Instead, it is treated as a data stream with very specific requirements not only in terms of priority, but also in terms of spacing between packets. The bandwidth budget required is reduced to that of the compression format used, so that a G.729 call only uses 8kbps over the ADSL link rather than the typical 42kbps. The practical result is that rather than a maximum capacity of three concurrent calls, 28 calls can be accommodated on a single broadband line.

We guarantee perfect voice quality over even small bandwidth,” explained Alex Fayn, who spearheaded the development of Q Box for Silver Networks, in an interview with PHONE+.  You could have 362kbps up and 786kbps down with 10 phones behind it, and we will guarantee quality both ways in and out.”

Fayn explained that while there are devices on the market that will control traffic going out, they cannot control traffic going in because they do not control the upstream router. The secret of our technology is that we install a device at your location and we take over all your traffic and deliver the traffic into our data center and then delivery your traffic to the Internet,” he said.

Sites that have Silver Networks Q Box links can be joined together to form private networks and backup links can be implemented and activated without losing calls in progress.

We can guarantee reliability by plugging into a secondary provider,” Fayn said. Essentially a customer could replace a T1 with a combination of cable modem and DSL. It will be cheaper and there will be redundancy.”

In addition, Q Box enables multiple links to be aggregated  as a single large bandwidth connection, offering a viable alternative to costly private circuits, the company said.

Another advantage of being able to use the lower bandwidth circuits is time to delivery. If a customer wants a solution delivered in one week, now we can do it with reliability and with quality where before we had to wait for the local loop to be delivered, which could be 30-45 days,” Fayn said.

Further, the company said with Q Box data transfer rates are not compromised by the fact that voice is present. Classes of data can be given their own share of available bandwidth in a more granular way than traditional QoS methods.