Mitel MIVOICE OFFICE 250, Руководство по установке и администрированию

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MiVoice Office 250 Installation and Administration Guide
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much storage resulting in 25% of the storage capacity, but it also produces better audio quality for
voice messages in some scenarios.
Systems equipped with a physical PS-1 do not offer a UVM vocoder selection because messages
are stored 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 UVM compression:
• In some environments where G.729 is used for IP phones, 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 system 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. Capacities are shown in Table 9 .
Table 9: Estimated UVM Storage Capacity
Compact Flash-Type
Card Size
Voice Mail Storage
(non PS-1/vPS-1) using
G.729 (default)
Voice Mail Storage
(non PS-1/vPS-1) using
G.726
Voice Mail Storage (with
PS-1/vPS-1) using
G.711
1 GB 6000 minutes
(100 hours)
1,500 minutes
(25 hours)
30,000 minutes
(500 hours)
2 GB 18,000 minutes
(300 hours)
4,500 minutes
(75 hours)
30,000 minutes
(500 hours)
NOTICE
Besides vocoder selection, items like freezes, log files, file-based MOH files, additional language
prompts, etc. can reduce available UVM storage capacity. As a result, many installations may require a
larger compact flash-type memory card in order to provide acceptable UVM storage capacity.
See the MiVoice Office 250 Enginerring Guidelines for more information on selecting the appropriate
card size.