The Intel VoIP program was a very successful trial on how to introduce VoIP into the enterprise using SIP and converging voice and data on the LAN. As the telephony industry moves from vertically integrated proprietary solutions to horizontal open standards architecture, a key challenge is to provide quality and reliable voice service on a mixed IP network. This project implemented a very basic voice quality and QoS strategy, proving that VoIP can be layered on top of an existing infrastructure with minor upgrades.

In terms of voice quality and QoS, the key learnings from this trial were as follows:

Voice Quality Plan: Intel benefited from having a deliberate plan up front. Enabling QoS leads to better and more predictable voice quality. This is a mandatory item for future deployments of any VoIP implementation in Intel. It is important to address voice quality holistically, from voice endpoint to voice endpoint.

Loading VoIP on a production LAN: Adding voice to an existing data LAN was important because it showed that the voice traffic did not impact the LAN functionality. It enabled the extrapolation of how scaling the pilot impacts the LAN from a capacity planning perspective. In addition, Intel received the benefit of managing only one network–one of the most touted benefits of VoIP. One major issue yet to be resolved is with IT security: end-to-end encryption may be required. If that is not possible, VoIP may reside on a separate voice network, which significantly degrades the business value but may improve voice quality.

Echo is a problem and difficult to diagnose: A considerable amount of time was spent diagnosing and fixing echo problems. Many possible sources/causes were identified, not all of which can be easily fixed. Trying to operate with mixed TDM and VoIP equipment makes it harder. Better industry-standard diagnostic tools would aid this process.

Headset selection is important: The appropriate headset selection is important for good voice quality. Wireless and less expensive wired headsets introduced noise and echo. The more expensive wired DSP headsets provided the best call quality.

G.711 Codec: G.711 is currently recommended for campus calls. Let gateways provide any necessary compression.

Drivers for VoIP include improved user mobility, functionality, presence, and productivity. Cost savings is on a case-by-case basis, with ROI and TCO improving as system costs decrease over time. In this case, the more specific business benefits we identified were as follows:

• Networks were simplified by converging voice and data networks.
• Costs related to data center space and telephone moves, adds, changes, and deletes were reduced.
• New or improved telephony applications were made possible due to VoIP's open, extensible architecture.
• The stage is set for advanced multimedia applications, services and productivity enhancements through converged communications.
• There is an immediate productivity gain from unified messaging, find/follow me, universal phone number, and presence integration.

These benefits can only be realized if acceptable voice quality is achieved.