Nortel Networks NN43001-504 User Manual

Page 62

Planning

Table 5
Multiple WLAN IP Telephony Manager 2245-10 and 2245-20 capacities

Number of
WLAN IP
Telephony
Managers
2245

Number of handsets
WLAN IP
Telephony
Manager
2245-10

Number of handsets
WLAN IP
Telephony
Manager
2245-20

not applicable

For example, if there are two subnets for handsets in a campus and some
handsets are directed to one subnet and some to the other, there are two
Call Admission Control domains operating independently. Specifically, if
both specified a limit of seven calls for each AP, it is possible to have seven
calls admitted by each WLAN IP Telephony Manager 2245 on the same
AP—therefore, the AP is oversubscribed by 2:1.

If multiple subnets are required, the best way to support them is to leverage
the Layer 3 WLAN IP Telephony Manager 2245 design. With this design, the
WLAN IP Telephony Manager 2245s are all in one subnet but SVP is routed
from the second client subnet. Although this is a supported configuration,
all the engineering guidelines for latency, jitter, and packet loss must still be
maintained. The Layer 3 design guidelines for having clients and WLAN IP
Telephony Manager 2245 in different subnets does not mean that the WLAN
IP Telephony Manager 2245 master and slaves can also be separated by
routers—they must still be collocated in the same VLAN (subnet).

WLAN handsets

The WLAN Handsets 2210/2211/2212/6120/6140

support both G.711 and G.729 codecs, but only using a 30 ms packetization
rate.

The WLAN IP Telephony Manager 2245 translates between packetization
rates, meaning that from the WLAN IP Telephony Manager 2245 to the
handset, the call uses the packetization rate specified by the CS 1000 (for
example, 20 ms). Nortel recommends that the CS1000 paketization rate
match the 2245 at 30ms. For BCM, the packetization rate must be 30ms.

Nortel Communication Server 1000

WLAN IP Telephony Installation and Commissioning

NN43001-504

01.02

Standard

Release 5.0

15 June 2007