To,fanli2000_0
这段解释我找了很久啊!不知道是否满足您的要求，本身ETSI规范资料太多啦！各位大侠最好将文档名称或具体那段资料上下文说明清楚啊
Facility Information Element (FIE)
This information element is the core element for the invocation, registration and every other action concerning supplementary services. It's 3rd octet contains the protocol profile identifier. The only three values defined for this identifier are the Remote Operations Protocol, the CMIP Protocol (see Q.941) and the ACSE Protocol (see X.217). These protocols are layer seven protocols.
REGISTER
This message is used for non call-associated transactions between subscriber equipment and a local exchange. Sending this message initiates the assignment of a new call reference. This is necessary if more than one transaction happens at the same time independent from each other.
FACILITY
This message is needed if transactions happen during the active state of a call. Beside the usual content of a Q.931 message (protocol discriminator, call reference and message type) it contains only two more info elements: the FIE and the Display info element.
