MPLS包头中有（）Bit的EXP，协议中没有明确，通常用作COS。
MPLS包头中有（）Bit的EXP，协议中没有明确，通常用作COS。
相关考题：
多协议标记交换(MPLS)是IETF提出的第三层交换标准，以下关于MPLS的描述中，说法错误的是(15)。A．传送带有MPLS标记的分组之前先要建立对应的网络连接B．MPLS标记具有局部性，一个标记只能在一定的传输域中有效C．MPLS支持各种网络层协议，带有MPLS标记的分组通常封装在PPP帧中传送D．路由器可以根据转发目标把多个IP流聚合在一起，组成一个转发等价类(FEC)
如下描述中,QOS对于MPLS标签中EXP字段的处理的原则正确的是() A.给IP报文封装MPLS标签时，直接将IP报文的TOS字段转换成MPLS标签的EXP字段B.标签交换（swap）操作时，EXP字段保持不变C.标签压栈（push）操作时，新压入的外层标签EXP字段继承内层标签的EXP字段D.标签弹栈（pop）操作时，如果弹栈之后是MPLS报文，不会将弹出标签的EXP字段复制到内层标签上；如果弹栈之后为IP报文，不会将EXP字段复制到IP报文的TOS字段
通常,MPLS包头中有()Bit用作标签(Label);3个Bit的EXP,协议中没有明确,通常用作COS;1个Bit的S,用于标识是否是栈底,表明MPLS的标签可以嵌套;8个Bit的TTL。 A.16B.19C.20D.24
Which two QoS classification and marking statements are true？ （）A、 In a Frame Relay network， delay sensitive traffic is tagged with the discard eligible （DE） bit.B、 In an MPLS network， the three most significant bits of the DSCP or the IP precedence of the IP packet are copied into the MPLS EXP field.C、 In an MPLS network， the MPLS EXP bits are used to identify up to 16 CoS values.D、 The differentiated services code point （DSCP） field consists of the first three bits of the IP precedence field in the header of an IP packet.E、 The 802.1Q standard uses a three bit field referred to as the user priority bits （PRI） to mark packets as belonging to a specific CoS.
Which two QoS classification and marking statements are true？（）A、 In a Frame Relay network， delay sensitive traffic is tagged with the discard eligible （DE） bit.B、 In an MPLS network， the three most significant bits of the DSCP or the IP precedence of the IP packet are copied into the MPLS EXP fieldC、 In an MPLS network， the MPLS EXP bits are used to identify up to 16 CoS values.D、 The differentiated services code point （DSCP） field consists of the first three bits of the IP precedence field in the header of an IP packet.E、 The 802.10 standard uses a three bitfield referred to as the user priority bits （PRI） to mark packets as belonging to a specific CoS.
Which statement about MPLS traffic engineering policy-based tunnel selection （PBTS） is not true？（）A、The tunnel that is not configured with the policy-class command acts as the defaultB、EXP selection is between multiple tunnels to the same destinationC、There is no requirement for IGP extensionsD、Tunnels are configured using the policy-class command and carry multiple EXP valuesE、It supports VRF traffic， IP-to-MPLS switching， and MPLS-to-MPLS switching
Which of the following is true about the MPLS header and its EXP field size？（）A、The MPLS header is 2 bytes，and the EXP field is 3 bits long.B、The MPLS header is 1 byte，and the EXP field is 3 bits long.C、The MPLS header is 4 bytes，and the EXP field is 3 bits long.D、The MPLS header is 3 bytes，and the EXP field is 3 bits long.
通常，MPLS包头中有（）Bit用作标签（Label）；3个Bit的EXP，协议中没有明确，通常用作COS；1个Bit的S，用于标识是否是栈底，表明MPLS的标签可以嵌套；8个Bit的TTL。A、16B、19C、20D、24
多选题Which two QoS classification and marking statements are true？（）AIn a Frame Relay network， delay sensitive traffic is tagged with the discard eligible （DE） bit.BIn an MPLS network， the three most significant bits of the DSCP or the IP precedence of the IP packet are copied into the MPLS EXP fieldCIn an MPLS network， the MPLS EXP bits are used to identify up to 16 CoS values.DThe differentiated services code point （DSCP） field consists of the first three bits of the IP precedence field in the header of an IP packet.EThe 802.10 standard uses a three bitfield referred to as the user priority bits （PRI） to mark packets as belonging to a specific CoS.
单选题Which of the following is true about the MPLS header and its EXP field size？（）AThe MPLS header is 2 bytes，and the EXP field is 3 bits long.BThe MPLS header is 1 byte，and the EXP field is 3 bits long.CThe MPLS header is 4 bytes，and the EXP field is 3 bits long.DThe MPLS header is 3 bytes，and the EXP field is 3 bits long.
多选题Which two QoS classification and marking statements are true？ （）AIn a Frame Relay network， delay sensitive traffic is tagged with the discard eligible （DE） bit.BIn an MPLS network， the three most significant bits of the DSCP or the IP precedence of the IP packet are copied into the MPLS EXP field.CIn an MPLS network， the MPLS EXP bits are used to identify up to 16 CoS values.DThe differentiated services code point （DSCP） field consists of the first three bits of the IP precedence field in the header of an IP packet.EThe 802.1Q standard uses a three bit field referred to as the user priority bits （PRI） to mark packets as belonging to a specific CoS.
多选题如下描述中，QOS对于MPLS标签中EXP字段的处理的原则正确的是（）A给IP报文封装MPLS标签时，直接将IP报文的TOS字段转换成MPLS标签的EXP字段B标签交换（swap）操作时，EXP字段保持不变C标签压栈（push）操作时，新压入的外层标签EXP字段继承内层标签的EXP字段D标签弹栈（pop）操作时，如果弹栈之后是MPLS报文，不会将弹出标签的EXP字段复制到内层标签上；如果弹栈之后为IP报文，不会将EXP字段复制到IP报文的TOS字段