ViBE helps to solve many of the everyday issues that are experienced when trying to make VoIP work effectively ‘in the real world’ in several important ways:
1 Quality of Service is implemented in a completely different way to traditional methods, being much more suited to slower links. ViBE Quality of Service (QoS) is implemented at both ends of link meaning that voice and data are controlled going in both directions. 2 Voice is no longer treated as simply another type of data which 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. 3 The bandwidth budget required is reduced to that of the compression format used, so that a G.729 call really does only use 8Kbit/s over the ADSL link rather than the 42Kbit/s which is more usual. Rather than a maximum of three calls, twenty-five calls are now practical on a single broadband line. 4 Voice and data can readily coexist on a single link. 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 much more granular way than traditional QoS. 5 Sites that have Vibe links can be joined together to form private networks, which means that security is easier to control. To prevent the intercept and decoding of data contained in ViBE VPN tunnels it can be configured to provide IPsec encryption of ViBE data packets. 6 Backup links can be implemented which can be activated without losing calls in progress. ViBE can be set to use an additional link in either an active or passive mode. In active mode ViBE efficiently bonds links of different speed together, reducing latency for larger packets. 7 Link bonding will allow multiple links to be used as a single large bandwidth connection, offering a viable alternative to costly private circuits. up to 8 internet links can be used to increase bandwidth connection. 8 Much more of the capacity of the link can be used.
Table showing possible number of calls using ViBE per 256kbps of bandwidth:
|Codec||With ViBE enabled each call will typically use:||Without ViBE including normal overheads each call will typically use:||No of Calls per 256kbps of bandwidth allocated for use with ViBE|
|G.729||8.1kbps||42.4kbps||28 (700% improvement)|
|G.711||64.1kbps||106kbps||3 (50% improvement)|
|G.722||32.1kbps||63.6kbps||7 (233% improvement)|
|GSM||13.1kbps||42.4kbps||17 (340% improvement)|
The table above assumes 20ms packet size. The % improvement figure is based on the number of calls that you could normally expect to maintain on a 256kbit/s upstream ADSL line when ViBE is not in use whilst still having the ability to transmit signalling data, though in reality 4 x G.729 calls plus data on a non-ViBE enabled 56kbit/s link is optimistic!