What are disadvantages of Network Address Translation Transparency?（）

• A、There is no disadvantage.
• B、It will add 16 bytes per packet of overhead(8 bytes UDP header, and 8 bytes of NON-IKE Marker).
• C、It will add 36 bytes per packet of overhead (20 bytes of IP header, 8 bytes of UDP header, 8 bytes of NON-IKE Marker).
• D、It will require that both crypto peers support this feature in the IOS version. Both crypto peers must also have this feature enabled.