Cisco Systems ATA187I1ARF Manual Do Utilizador
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Cisco ATA 187 Analog Telephone Adaptor Administration Guide for SIP (Version 1.0)
OL-21862-01
Chapter 1 Cisco ATA 187 Analog Telephone Adaptor Overview
Software Features
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V.44
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K56Flex
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ITU-T V.34 Annex 12
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ITU-T V.34
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V.32bis
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V.32
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V.21
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V.22
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V.23
Fax Services
The ATA 187 supports two modes of fax services, in which fax signals are transmitted using the G.711
codec:
codec:
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Fax pass-through mode—Receiver-side Called Station Identification (CED) tone detection with
automatic G.711A-law or G.711µ-law switching.
automatic G.711A-law or G.711µ-law switching.
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T.38 Fax Relay mode: The T.38 fax relay feature enables devices to use fax machines to send files
over the IP network. In general, when a fax is received, it is converted to an image, sent to the T.38
fax device, and converted back to an analog fax signal. T.38 fax relays configured with voice
gateways decode or demodulate the fax signals before they are transported over IP.
over the IP network. In general, when a fax is received, it is converted to an image, sent to the T.38
fax device, and converted back to an analog fax signal. T.38 fax relays configured with voice
gateways decode or demodulate the fax signals before they are transported over IP.
Note
Success of fax transmission depends on network conditions and fax modem response to these conditions.
The network must have reasonably low network jitter, network delay, and packet loss rate.
The network must have reasonably low network jitter, network delay, and packet loss rate.
Methods Supported
The ATA 187 supports these methods. For more information, see RFC3261 (SIP: Session Initiation
Protocol).
Protocol).
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REGISTER
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REFER
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INVITE
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BYE
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CANCEL
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NOTIFY
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OPTIONS
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ACK
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SUBSCRIBE