VoIP gets upwardly mobile

Different handsets and other hardware can help make a voice over Wi-Fi deployment, muses Rob Leggett

Rob Leggett: For interoperability with the widest range of IP PBXs, users should choose a handset that supports session initiation protocol

Voice over Wi-Fi, also known as mobile VoIP, can link a company’s wireless LAN (WLAN) to its PBX, helping organisations increase the reach, reliability and security of their wireless networks and deliver data and voice wherever needed.

Juniper Research has claimed that the global voice over Wi-Fi handset market will grow to almost US$70bn revenue by 2012.

An Aberdeen Group survey of 200 organisations in October 2008 suggested workforce productivity could rise by 51 per cent when voice over Wi-Fi is deployed, due to workers making better use of their available time.

Voice over Wi-Fi can help where employees remain on the corporate premises but spend a lot of time away from their desks. Examples include retail, warehousing and manufacturing organisations.

These types of businesses typically have a wired back office for administration, with WLAN linking laptops or handhelds to the network.

Staff who work on the floor could be equipped with voice over Wi-Fi handsets and have their PBX calls routed over the WLAN, making staff accessible, and making it easy for them to make, receive and transfer calls.

Mobile phones generally cannot be used in hospitals, but most wards already have wireless networking. A hospital with an IP-based PBX can keep contact with clinical or administrative staff all the time, no matter where they are in the building.

Some handsets support integration with existing paging or alert systems too.

The hospitality sector also already makes use of wireless networking that can also be used for employees’ voice calls. Voice over Wi-Fi can also be provided temporarily for guests or delegates attending events.

For interoperability with the widest range of IP PBXs, users should choose a handset that supports session initiation protocol (SIP) to ease deployment.

It goes without saying that you should still ensure the handset provides the call features you need such as hold, transfer, conference and message waiting notifications.

Look for phones that conform to enterprise security policies for wireless. This usually means support for WPA2 and 802.1X.

There is also a standard for call quality: handsets should support the Wi-Fi Alliance's Wi-Fi Multimedia (WMM) specification, a feature set to optimise QoS for voice and video over Wi-Fi. Look also for fast roaming to ensures call quality is maintained as users move between access points.

For easy management, check out handsets that automatically configure all parameters and software updates across WLAN. The alternative is doing a huge amount of manual configuration by phone keypad.

DoIt is also important not to overlook battery life. Because the handset is used like a mobile, long talk time of at least four hours, and standby of 50 or more hours is useful.

Rob Leggett is sales director of value-added distributor Siracom