多项选择题 WhichthreestatementsaboutIOSFirewallconfigurationsaretrue？（）

单项选择题 Refer to the exhibit. MPLS has been configured on all routers in the domain. In order for R2 and R3 to forward frames between them with label headers, what additional configuration will be required on devices that are attached to the LAN segment?（）

单项选择题 Refer to the exhibit. The show mpls interfaces detail command has been used to display information about the interfaces on router R1 that have been configured for label switching. Which statement is true about the MPLS edge router R1?（）