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BY: FLEISHMAN-HILLARD
When assessing the current readiness of a company's infrastructure for a VOIP (voice over Internet Protocol) implementation, it is essential to bear in mind that voice over the data line has a significant impact on network architecture while interoperability with other applications (excluding call centre applications) is minimal.
"Once this has been internalised, the first aspect to look at is the hardware or network," says Noel Wait, business development manager at Business Connexion's networks competency. "More often than not, a network upgrade will be required to accommodate VOIP and companies must weigh up this costs against business benefit before they delve into anything."
A good starting point is to evaluate the network to ensure it has adequate bandwidth to carry the heavier load that VOIP traffic will entail. All networks and switches must support the 802.1p specification, which allows voice packets to be given priority. Without such priority, voice quality will suffer greatly from "jitter".
Switches must be powered. This can be achieved by establishing a Power over Ethernet (PoE) environment so that electricity is supplied to the handsets via either a powered switch or mid-span power injector.
All equipment that handles voice traffic, including the PBX itself, plus all the switches and routers between it and the handsets, must be supported by an uninterruptible power supply (UPS) so that the phones work when there's a power outage (similar to the functioning of conventional phones in these conditions). Another issue that needs to be taken into consideration is security. The security measures that protect the enterprise network (vulnerability management, firewalls, intrusion detection, virus protection and encryption) will also protect VOIP activities.
"However, the VOIP system needs management security protection (dial-ins, password protection and call-backs) so that internal users are prevented from accessing administrative functions. These are serious issues that are part of standard practice within any IT department," says Andy Brauer, Chief Technology Officer at Business Connexion's Networks Competency. In addition to these, the infrastructure can be evaluated using the following criteria
1. Feasibility - ability of the vendor to evaluate existing infrastructure and vet it for VOIP
2. Resiliency - ability of the system to withstand adverse conditions and recover after a catastrophe
3. Availability - capacity to handle current peak or "busy-hour" traffic in the present
4. Scalability - ability to handle "worst case" expansion (in number of lines) over at least the medium-term (5+ years) without requiring a major upgrade
5. Protocols supported - support for SIP in particular is important, as SIP appears to be the protocol of choice for multimedia applications, including not only voice but video as well
6. Clear product roadmap - in addition to the above, it's important to evaluate the feature set. This can involve literally hundreds of features, most of which can easily be implemented at any time. This is not always possible in the case of conventional PBXs where the addition of new features can be more complex. |