Bfd
abbr. 双向转发检测机制（Bidirectional Forwarding Detection）；发现路由器转发故障的新协议；二进制文件描述符（Binary File Descriptor）
🗣️ 情景例句
The checkout counters are very busy.
收款台都很忙。
The television set is out of order.
这电视机出毛病了。
may have left an automatic messenger behind to await the possible awakening of an advanced civilization.
很可能会在离开太阳系时留下自动化信息装置，等待先进文明的觉醒。