| Signalling
sequence 2 (call setup) |
| User A |
| LE A |
| TE |
| LE B |
| User B |
| Initial address message
(IAM) |
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| ISUP message
IAM is sent to transit exchange. |
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| Transit
exchange analyzes B number and |
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| determines that
call should be routed to local |
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| exchange of user B (LE
B). |
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| IAM message is
sent to LE B. |
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| Within all
exchanges, the path is cut through |
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| (circuit
switched path between user A and LE B). |
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