Telcordia LERG Routing Guide
（重定向自LERG）
The Telcordia LERG Routing Guide is a comprehensive data product produced monthly by the Telcordia Routing Administration (TRA). It is primarily used by telecommunications service providers operating within the North American Numbering Plan (NANP), which is World Zone 1. Its data supports the current local exchange network within the NANP and identifies reported planned changes in the network. The acronym "LERG" originally stood for Local Exchange Routing Guide, and is a trademarked term of Telcordia Technologies, Inc., now a division of Ericsson.