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Voice over IP (VoIP)VoIP System Telephones
Features | Notes |
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Blind Transfer | SIP only: forwarding an incoming call without |
| accepting the call; feature must be supported by SIP |
| telephone or by the SIP software. |
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Keypad as “INFO” | DTMF tones cannot be securely transferred “in band” |
message | via compression codecs. Digital “out band” transferral |
| as “INFO” SIP message is supported. This feature must |
| be available and activated on a SIP telephone or in |
| the SIP software. |
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7.4VoIP System Telephones
The following telephones and software packages are available for VoIP system telephony:
■Aastra 6773ip (OpenPhone 73 IP): This system telephone can be extended with up to three key extensions Aastra M671.
■Aastra 6775ip (OpenPhone 75 IP): This system telephone can be extended with up to three key extensions Aastra M671 or Aastra M676).
■Aastra 277xip (OpenPhone 7x IPC): This VoIP software offers the functionality of an IP system telephone using Windows 2000/XP executable software (see Aastra 277xip (OpenPhone 7x IPC) starting on page 79). This software also pro- vides local answering machine functionality and can be integrated into CTI applications.
■The older VoIP system telephones OpenPhone 63 IP and OpenPhone 65 IP can still be used.
7.4.1 Device Properties
The VoIP system telephones offer the following specific device properties:
■Two RJ45 connector ports are available for ethernet connection. The ports are connected to one another via the telephone’s internal switch. The switch sup- ports 10 Mbit/s or 100 Mbit/s
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