| 摘要 |
ESQK and/or ESRK (ESxK) number pool exhaustion and reuse errors are eliminated by replacing the ESxK identifier with an emergency services pseudo key (ESPK) identifier. A positioning center (MPC/VPC) replaces an ESxK received with a query with a ESPK in a return message. The ESPK is either a unique 10-digit number or unique alpha-numeric identifier that can be used to re-query the source of dynamic ALI data. The ESPK may be generated using, e.g., unique prefixing, suffixing, or randomizing. The ESPK is a non-constrained, unique identifier that preferably remains unique for the call instance over an extended period of time. The ESPK is used for any subsequent ALI request for the call. Each time a positioning center receives a query with ESPK, it is directly associated with, and returns, the updated location for the original emergency call, regardless of whether or not the original ESxK was reallocated to another emergency call. |
