How to get a Callee ID?

Hello, Guys:
my case is that i have PRI service, there are 100 numbers. if callers call in, the asterisk will able to know the [color=red]callee number[/color], [color=red]not caller number. [/color]. how to receive the callee number. for example, if 6611 calls 9911, asterisk will get 9911, not 6611.
anyone has a idea for this problem?

You mean EXTEN?

isn’t this the DID?

that’s what i was going to say…to even be able to route the calls, you need the DID, unless you are dumping every inbound into the ‘s’ extension…

hello, guys and whoiswes:
I do not know hot to get DID number. if i have set a DID number, it’s possible to use dialplan to get it? and how to get it.