Cisco has just enhanced its 802.11 Cisco Wireless IP Phone 7920 with additional Cisco CallManager IP PBX calling features, integrated corporate directory and calendar, XML application support, and security capabilities.

In addition, Cisco says the latest release of its Cisco Compatible Extensions (CCX) software for client devices, Version 4.0, is focused on voice support. Cisco says CCX 4.0 is with CCX partners now and should be in mainstream products by year-end.

First, let's discuss the phone, which received a firmware upgrade (to Release 2.0) in late June.

Wi-Fi phones start to catch up
Generally, 802.11 phones have lagged behind certain counterpart devices in a few areas. For example, they've struggled to achieve calling-feature parity with wired VoIP phones. Also, they usually aren't as secure as data Wi-Fi devices. Finally, the industry is still working on getting battery life to approach that of cellular phones, which can "sleep" between conversations and conserve power.

The latest 7920 enhancements address the first two issues. The handset now supports the phone features of Cisco CallManager, Release 4.0, including shared lines, conferencing, and two calls per line. Users with multiple-line phones can now configure different ring tones for each line on their phone. In addition, users already on a call can receive an audible alert of another incoming call or message.

Cisco Wireless IP Phone 7920 users now can also access both Web-based and custom XML applications by using a new directory option on the phone called "Services."

For example, Cisco says about 300 developers have built XML applications that work with Cisco CallManager wired VoIP phones and that many of those, including the Emergin nurse call system, will now port over to the 7920.

Security making progress
As per security, the 7920 isn't yet on a par with data devices, but has made strides, now supporting the following:

  • Wi-Fi Protected Access (WPA).


  • Cisco Centralized Key Management (CCKM) and a wireless domain server (WDS) for fast reauthentication during roaming.


  • Temporal Key Integrity Protocol (TKIP) and Message Integrity Check (MIC) for improved encryption.

Admission control, integrated QoS join CCX
The latest release of Cisco Compatible Extensions software, Release 4.0, is more voice-centric than previous ones.

The release is in CCX partners' hands now and is expected in the commercial marketplace by year-end. CCX-v4 reduces handoff time across access points, thereby decreasing latency, and extends battery life, says Pat Calhoun, CTO in Cisco's Wireless Networking Business Unit.

The CCX program is one in which suppliers of WLAN client devices and chips license, at no charge, Cisco WLAN technology in a specification. Participants implement all elements of the spec and then have them tested for compliance and interoperability with Cisco Wi-Fi infrastructure products at an independent test lab. Calhoun says that about 90 percent of 802.11 silicon that ships today is CCX-enabled.

At the network layer, Calhoun says, CCX-v4 has features to integrate QoS across the wired and wireless sides of the network in a consistent way. In addition, Call Admission Control (CAC) is rolling into CCX v.4 "with all the tools for building a complex IP telephony environment."

CAC capabilities will help manage a high density of users and balance the load among access points, Calhoun explains. "Admission control looks at the network as a whole, moving phones [among] APs to balance and prioritize traffic," he says.

For expanded handset support, Cisco's CallManager IP PBX is slated to support Session Initiation Protocol (SIP) on the line side by year-end. Third-party handset makers that are starting to offer 802.11-capable devices (such as Research In Motion and Nokia) tend to support SIP-standard calling features, which should expand the number of phone options users have on a Cisco (or any other SIP-capable) 802.11 VoIP network.