It has to do with the translations built in LD 90 and your RLIs in LD 86. When you dial your NARS/BARS access code, the digits that follow are first checked against your NPA, NXX & SPN tables. Then, if a valid entry is found, the call is sent to the speicified RLI that determines if the originating TN has permission to make such a call before sending it to the route specified in the RLI. When you dial the ACOD for a route, you bypass all the translations in the switch. All digits that follow the ACOD are outpulsed directly on the trunk and sent to the far end switch, CO, POP, etc. When you dial the ACOD, you have free riegn to dail whatever you want. Whether or not the far end switch, CO, POP, etc completes the call is another story. That depends on what services you are paying your provider for.