The IEEE has approved 802.11e late last month (Sept. 2005).

The 802.11e specification allows packets to gain priority by defining
four traffic classes, each with its own queue. By default, they would
be for voice, video, best-effort and background, said Ben Guderian,
vice president for market strategies and industry relations at
SpectraLink. The definitions of the four classes could be changed from
the default. To identify the class of each packet, the standard uses
markers similar to ones used in wired Ethernet, he added. Seeing those
markers, an access point could give voice packets top priority for
transmission, followed by video, and so on, he said..

Touted as a boon for voice over IP network applications (VoIP), this is
the last piece to fall into place that frees life critical wireless
applications from private subnets to run on hospital's general
networks. As wireless applications have proliferated in hospitals, CIOs
have struggled with ways to round all these point solutions into an
enterprise frame work. Most vendors have resisted, claiming life
critical data and life threatening alarms could be missed. Between the
lines, medical device vendors also don't want to give up the simplicity
of running on their own private networks. Running across the hospital's
network backbone subjects them to IT network management snafus, the
requirement to maintain broader network management expertise
(especially broader vendor support), and limited support hours (8x5 vs
24x7).

Hospitals with paperless charting and CPOE should already provide the
network reliability required for life critical data. These IT
departments provide 24x7 support just like the Biomed department, and
monitor networks for latency and capacity. Migrating medical devices
onto the IP backbone still has its challenges; not all vendor systems
(nor vendor support resources) are able to run anywhere but on private
subnets.

As with any new standard, there still some differences of opinion, and alternative approaches.

The problem with 802.11e is that it puts the power to request
priority in the client, [IDC analyst, Abner] Germanow said. As a result, "anyone has the
ability to mark e-mail as high-importance," he said. In larger
deployments more control will have to reside in centralised servers or
network mechanisms, he said.

As a
result, the process of standardising priority in wireless LANs may be
just beginning, Germanow said. Vendors such as Meru Networks already
offer mechanisms better suited to large enterprises, and it's likely
that vendors will try to put more advanced technology into another
standard that would go into wireless LAN gear alongside 802.11e, he
said.

However, the new standard is
good enough for now, because the use of applications that need quality
of service (QoS) guarantees on wireless LANs is still limited, Germanow
said.

You may recall, Draeger uses a network appliance to provide QoS for their wireless patient monitors running over hospital networks.