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Next, we have to glue all things together. Calls from E1 are directed into context fpstn, calls from SIP are directed into context sip. Now we should define routing rules for this contexts. We assume that operator sends entire number as DNID and we have 9digits country dialplan. Replace 123456 by your PBX prefix. We will reach outside world using 0 as prefix. In fact, this is realy very simple config. In real world, we should use macros and better error reporting. \ ${EXTEN:6} means that we will strip first six digits from number. Similary, \ ${EXTEN:1} strips one number from left side. For testing purposes, we created extensions 111, which answers call and do simple echo application. You must have asterisk sounds instaled to make it working.
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