Why is cloud IPSEC limited to 1.25G?

The correct answer highlights the capability of using multi-core virtual machines (VMs) to overcome the bandwidth limitations of cloud IPsec, which is generally capped at 1.25 Gbps due to the nature of how IPsec tunnels are established. Native solutions often route traffic through a single core, thus creating a bottleneck that limits throughput.

By utilizing multi-core VMs, organizations can distribute the encryption workload across multiple cores, effectively increasing throughput beyond the 1.25 Gbps limit. This enhances the performance and scalability of IPsec in cloud environments, allowing for more efficient handling of data traffic and meeting higher bandwidth requirements.

In contrast, the other choices do not address the limitation of IPsec directly in the same way. While native solutions connecting through a single core can contribute to performance issues, simply acknowledging that does not provide a solution. The mention of private connectivity like ExpressRoute and Direct Connect being encrypted by default pertains to a different topic of connection types and their inherent security rather than addressing the specific issue of IPsec bandwidth limits. Lastly, the assertion that cloud providers cannot provide encryption at all is inaccurate, as cloud providers do offer various encryption solutions, including IPsec, but with noted limitations.