Specifications

Chapter 4: Specifications
Voice Message Storage Capacity
Page 4-18 Mitel
®
5000 Installation Manual – Issue 3.0, October 2008
Voice Message Storage Capacity
Basic Voice Mail (BVM) storage capacity has changed with the introduction of the G.726-32
option as an additional voice compression selection.
G.726-32 uses 32 kbps while the default G.729 compression uses 8 kbps. The default BVM
compression is set to G.729 to maximize voice mail storage capacity, and the previously
published voice mail capacities are based on G.729 compression. Using G.726-32 consumes
four times as much storage resulting in 25% of the storage capacity, but it also produces better
audio quality for voice messages in some scenarios.
The CS-5600 BVM does not offer a vocoder selection because it stores voice messages on the
PS-1 hard disk. Since storage is plentiful, no compression is used (G.711). There are some
scenarios in which G.726-32 may be appropriate for BVM compression:
• In some environments where G.729 is used for IP endpoints, multiple compression/
decompression steps may result in degraded voice quality of the stored messages. Using
G.726-32 for voice mail storage may improve the quality of recorded voice.
• The VPIM feature, as specified in the VPIM standard, natively uses G.726-32 compression
for the interchange between voice mail systems. By using G.726-32, the Mitel 5000 does
not need to transcode from G.729 to G.726-32. The result is more efficient processing.
If the resulting voice storage capacity is unacceptable, customers should upgrade to a larger
compact flash-type card. Compact flash-type cards of 256 MB are not supported in this v3.0
release (see the NOTICE above). Capacities are shown in Table 5.
NOTICE
The Mitel 5000 v3.0 release requires a minimum 512MB compact flash-type memory card. If
this system is currently using a 256MB compact flash-type memory card, upgrade the card to
either 512MB (part number 841.0274) or 1024MB (part number 841.0273) before upgrading
the system to v3.0.
Table 5. BVM Storage Capacity
Mitel Memory Card w/American
English Prompts using G.729
(default)
Mitel Memory Card w/American
English Prompts using G.726-32
(optional)
BVM on PS-
1 Hard Disk
512 MB 1024 MB 512 MB 1024 MB
Mitel CS-5200/5400 5,420 min
(90.33 hr)
N/A
Mitel CS-5600 N/A N/A N/A N/A 30,000 min
(500 hr)