The X.500 standard is costly and complex,but it supports features -- such as replication -- that make it possible to construct a centralized directory.是什么意思_The X.500 standard is costly and complex,but it supports features -- such as replication -- that make it possible to construct a centralized directory.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句