| Primary
rate access – user interface |
| U |
|
|
|
| Line |
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| Termination |
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| PBX |
|
|
|
|
|
| PBX |
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| equipment |
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| manufacturer |
||||
| specific |
||||
| solutions |
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|
|
|
|
|
| Standard
2 Mb/s |
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| TDM
connection |
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| (PDH or SDH) |
||||
| Exchange |
| 64 kb/s D
channel in one PCM time slot |