2、2,缩略语.AC,Access,Control,List。访问控制列表 BHCA、Busy Hour,Call Attempts,忙时呼叫尝试次数,ID,Identification。身份证明 IP,Internet。Protocol。互联网协议、LPZ,Lightning,Protection Zone、雷电防护区。MAC.Media,Access,Control。媒体控制访问.MPLS.Multi Protocol。Label,Switching。多协议标签交换.MSTP,Multi,Service。Transmission,Platform,多业务传送平台,NAT.Network,Address.Translation.网络地址转化,NTP,Network Time.Protocol 网络时间协议.OTDR、Optical。Time,Domain.Reflector、光时域反射仪、PDH、Plesiochronous Digital,Hierarchy.准同步数字系列,PTZ。Pan.Tilt and。Zoom.control,云台操控、PRBS,Pseudo、Random Binary,Sequence,伪随机二进制序列 QoS Quality、of,Service、系统服务质量,SDH,Synchronous.Digital、Hierarchy.同步数字系列 STM。N Synchronous,Transport.Module level、n.同步传输模块n级,UPS Uninterruptible Power,Supply。不间断电源.VLAN.Virtual,Local Area Network,虚拟局域网,VPN。Virtual.Private.Network、虚拟专用网