【判断题】
DWDM传输系统网络同步时钟采用主从同步方式,各个网元通过SDH运载的2Mb/s支路信号传送的定时同步信号使用。()
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相关试题
【判断题】
DWDM和CWDM的区别在于复用波长的频率间隔不同。
【判断题】
DWDM可以实现无电中继传输最长距离640km。
【判断题】
DWDM目前使用的传输窗口主要是1550nm窗口。
【判断题】
DWDM系统使用的光源具有两个突出的特点是:比较高的色散容限和标准而稳定的波长。
【判断题】
E1接口共32时隙,每时隙速率为64Kbps,64Kbps*32=2,048,000bps,故E1口又称为2M口。
【判断题】
EPON系统在分光比为1:32下平均每个ONU分配到约30Mbps,带宽是不可调
【判断题】
F820的主控板是MS8E,可支持8个以太网端口;F821的主控板为MSVE,可支持8个以太端口中。
【判断题】
F820最多可提供24*FE口或8FE口,32voip口
【判断题】
FTP是基于UDP的,而TFTP是基于TCP的。
【判断题】
FTTB类型ONU在修改数图匹配方式是通过修改控制点的方式来做的,即修改49号控制点,如:将匹配方式调整为最小匹配,就需要将该控制点的值调整为0。
【判断题】
G.652光纤指在1310nm波长窗口的色散性能最佳,又称之为色散未移位的光纤(也就是0色散窗口在1310nm波长处),它可以应用于1310nm和1550nm两个波长区;()
【判断题】
GFM-2000铅蓄电池产品型号中G代表固定型、F代表防酸隔爆式、M代表密伐式,2000代表额定容量2000AH。
【判断题】
GPON OLT每PON口可支持1:64的分光
【判断题】
GPON ONU的PON口上采用的尾纤类型为SC/APC。
【判断题】
GPON 网络中的下行速率2.5Gbps表示整台OLT有2.5G的下行带宽。
【判断题】
GPON的下行业务转发采用TDMA机制。
【判断题】
GPON技术中,一个gem可以绑定到一个Tcont中,一个Tcont可以绑定多个gemport。
【判断题】
GPON接入方式,采用IMS+OLT+GPON ONU方式,与传统通信方式不同,GPON接入以传统模拟线将用户语音通信接入到移动IMS核心网,同时为用户提供IMS业务。
【判断题】
GPON接入网丢包率是指从OLT上联设备至ONU设备的PING包丢包率。
【判断题】
GPON系统的两种DBA带宽分配方式SR和NSR的区别主要取决于ONU支不支持带宽上报。如果支持,则默认就会使用SR,反之就是NSR。
【判断题】
GPON最大分光比为1:64,采用两级分光,分光比分别为1:16和1:8。
【判断题】
HDB3码中用“取代节”取代长连“0”码是为了有利于减少直流成分。
【判断题】
HP-TIM 是因检测到高阶 POH 中的 J1 字节收发失配引起。
【判断题】
ICMP协议可以把公网的IP地址转换为私网的IP地址
【判断题】
Internet中的一台主机只能有一个IP地址。
【判断题】
IPv4报头的最小长度为20字节,那么IPv6报头的长度为40。
【判断题】
IPv6包头比IPv4包头更长,格式比IPv4复杂
【判断题】
IPv6采用128位长度的地址格式,2000::1是一个非法的IPv6地址
【判断题】
IPv6地址长度是IPv4的4倍,采用8段十进制数表示,中间使用冒号隔开
【判断题】
IPV6是下一版本的互联网协议,采用32位地址长度,可不受限制提供地址
【判断题】
IPv6在选路时也可以使用IPv4使用的RIP,OSPG,BGP等动态路由协议
【判断题】
IP报文每经过一个网络设备,包括Hub、Lan Switch和路由器,TTL值都会被减去一定的数值
【判断题】
IP被认为是不可靠的机制,因为它不保证发送。
【判断题】
IP城域网是CMNET省网在城域内的延伸,IP城域网在网络层次上包括核心层和业务接入控制层。
【判断题】
IP地址由网络号和主机号组成,B类地址的主机号部分有16比特,能容纳的最大主机数为65534
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Because of the boring ___, we need to take a vacation every year.
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C. rifle
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The manager spoke highly of such ___ as loyalty, courage and truthfulness shown by his employees.
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