IP SAN (Internet Protocol Storage Area Network) typically uses Ethernet networks to connect servers and storage systems, utilizing the IP protocol suite. While Fibre Channel SANs often use optical networks, IP SANs do not inherently require such infrastructure. Therefore, the statement that IP SAN uses underlying optical networks is incorrect.

Software Defined Networking (SDN) is best described as the decoupling of the data plane and control plane in networks. This architectural approach allows for more flexible and programmable network management, where the control plane is abstracted from the physical hardware and can manage the network through software, enabling dynamic and efficient control over network traffic and resources.

The rebuild time for a failed disk in Disk Domain B is shorter than for a failed disk in Disk Domain A. This is because there are fewer disks in Domain B, which means there is less data to redistribute and rebuild. Hence, a failed disk in a smaller disk domain will typically have a faster rebuild time compared to one in a larger disk domain.

RAID 2.0+ is an evolved version of RAID technology that incorporates improvements over traditional RAID systems, making statement 1 true. Additionally, RAID 2.0+ offers excellent rebuild characteristics with enhanced performance and reliability during the rebuild process, making statement 2 true as well.

Statement 1 is false because MLC (Multi-Level Cell) drives are generally not optimal for high-intensity writes due to their lower durability compared to SLC (Single-Level Cell) drives. Statement 2 is also false because the latency of SSD drives is typically much lower than 0.1 seconds; it is usually in the range of microseconds to a few milliseconds.