Tek-Tips is the largest IT community on the Internet today!
Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!
-
Congratulations gkittelson on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!
SPU4 board
- Thread starter Option43
- Start date
Hi, from Alex IP networking:
DTMF tones could traverse the data network within the audio channel. However, this has a number of drawbacks. First, the audio stream can be encoded/decoded using different codecs along the data network. Moreover, audio stream is conveyed using a non-reliable transport protocol (UDP protocol), which means that the packets carrying audio data can be lost. These facts may cause DTMF tones to be unidentifiable by the end user.
In order to transport the DTMF tones reliably through the network, they must be conveyed in the signalling channel. It requires that DTMF tones received in the audio stream (in-band) from other signalling systems in the ASB 501 04 system have to be detected, extracted from the audio stream and converted into H.245 signalling i.e. H.245 UserInput indication messages.
The detection of the DTMF tones received as in-band tones is done by means of the SPU4 board. The SPU4 board is used instead of the more common TMU board due to its improved capacity to detect and extract the in-band DTMF tones. Using the SPU4 board the in-band DTMF tones can be delivered reliably through the IP network minimizing the disturbances in the audio quality.
In order to detect the in-band DTMF tones and extract them from the audio stream the SPU4 board is connected in serial with the existing speech path. The following picture depicts this connection.
And for remote extension:
To be able to offer the Mobile extensions/Fixed remote extensions the possibility to request services like Inquiry, Paging, Alternation and Conference a specific procedure for the remote extension (which is requested by suffix digits) is used to simulate the R/earth button. To be able to detect the suffix-procedure digits (DTMF tones), a Key Code Receiver has to be connected during speech state to receive requests from the Mobile extension/Fixed remote extension.
The number of key code receivers is limited to 32 on each SPU4 board. The maximum number of simultaneous remote extension calls in one LIM before reaching congestion of key code receiver depends on the number of SPU4-boards installed per system.
DTMF tones could traverse the data network within the audio channel. However, this has a number of drawbacks. First, the audio stream can be encoded/decoded using different codecs along the data network. Moreover, audio stream is conveyed using a non-reliable transport protocol (UDP protocol), which means that the packets carrying audio data can be lost. These facts may cause DTMF tones to be unidentifiable by the end user.
In order to transport the DTMF tones reliably through the network, they must be conveyed in the signalling channel. It requires that DTMF tones received in the audio stream (in-band) from other signalling systems in the ASB 501 04 system have to be detected, extracted from the audio stream and converted into H.245 signalling i.e. H.245 UserInput indication messages.
The detection of the DTMF tones received as in-band tones is done by means of the SPU4 board. The SPU4 board is used instead of the more common TMU board due to its improved capacity to detect and extract the in-band DTMF tones. Using the SPU4 board the in-band DTMF tones can be delivered reliably through the IP network minimizing the disturbances in the audio quality.
In order to detect the in-band DTMF tones and extract them from the audio stream the SPU4 board is connected in serial with the existing speech path. The following picture depicts this connection.
And for remote extension:
To be able to offer the Mobile extensions/Fixed remote extensions the possibility to request services like Inquiry, Paging, Alternation and Conference a specific procedure for the remote extension (which is requested by suffix digits) is used to simulate the R/earth button. To be able to detect the suffix-procedure digits (DTMF tones), a Key Code Receiver has to be connected during speech state to receive requests from the Mobile extension/Fixed remote extension.
The number of key code receivers is limited to 32 on each SPU4 board. The maximum number of simultaneous remote extension calls in one LIM before reaching congestion of key code receiver depends on the number of SPU4-boards installed per system.
summerdike
Instructor
SPU4 is used for remote extension in BC12 for the remote (fixed/mobile) users be able to use dtmf.
______________________________
"Reload and Restart Requested
System Initiated"
______________________________
"Reload and Restart Requested
System Initiated"
- Status
