Smashing the VoIP performance barrier

VOIPBOX appliances provide dramatic acceleration of Voice over IP (VoIP), with up to 10x more calls over an ADSL line.

Limitations of VoIP

• Voice calls are symmetrical in terms of bandwidth requirements; they need the same amount upstream and downstream. The number of simultaneous calls is limited by the slower upload speed (typically 256Kbit/s).
• Voice information can be compressed to use only 8kbit/s per call. However, the way it is packaged for broadband networks means each call typically ends up using at least 42kbit/s.
• Standard QoS techniques do not work very well for voice carried over links with less than about 1000Kbit/s. Voice information gets delayed because it has to wait for a free slot on the link in order to be sent. Since people's voices do not incorporate such delays this causes issues with voice quality.
• In addition, standard QoS techniques can not allocate more than 70% of the available link bandwidth reliably. So, on a standard broadband link, three calls is the absolute maximum that can be achieved before quality starts to suffer.
• Broadband is usually part of a public or shared network, making security a concern.
  

Smashing the VoIP performance barrier

• VOIPBOX is powered by revolutionary Vibe technology. This delivers ground-breaking performance by addressing the technical limitations of VoIP.
• Voice is treated as a data stream with very specific requirements in terms of priority and spacing between packets, allowing more of the capacity of the link to be used.
• The bandwidth budget is reduced to that of the compression format used, so that a G.729 call really does use 8Kbit/s over the ADSL link.
• Voice and data can readily coexist on a single link. Classes of data can be given their own share of available bandwidth in a much more granular way than traditional QoS.

VOIPBOX enabled sites can be joined together to form private networks, which means that security is easier to control.

ADSL lines can be bonded providing more bandwidth and resilience allowing the loss of a line without losing calls in progress.

 

Codec	With VOIPBOX each call uses	Without VOIPBOX each call uses	No. of calls per 256kps of bandwidth with VOIPbox
G.729	8.1kps	42.4kps	28 (+700%)
G.711	64.1kps	106kps	3 (+50%)
G.722	32.1kps	63.6kps	7 (+233)
GSM	13.1kps	42.4kps	17 (+340)

 

VOIPBOX delivers huge performance increases. These translate into major benefits: cost savings and QoS improvements in either enterprise WANs or Service Provider networks.

 

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