RouterA will ignore IP options on packets, and features that rely on IP options, such as Resource Reservation Protocol (RSVP) and Internet Group Management Protocol version 2 (IGMPv2), might not function properly. The ip options command can be used to specify what a router does with packets that include IP options.

The syntax of the ip options command is ip options {drop | ignore}. The ip options drop command configures the router to drop all packets with IP options. The ip
options ignore command configures the router to ignore IP options on packets. When both commands are issued on a router, the ip options ignore command takes priority; therefore, RouterA will ignore IP options on packets.

RouterA will not remove IP options on packets. The ip options command does not include a keyword that can remove IP options from packets. Threats that exploit IP options will be mitigated for RouterA. However, these threats will not be mitigated for downstream devices, because RouterA will continue to forward packets with IP options. If the ip options drop command were the only ip options command issued on RouterA, threats would be mitigated for RouterA as well as for downstream devices.