Security architecture, cloud security, and presales engineering notes from Faisal Khan — CISSP, CCSP. https://securitybyfaisal.com/ en-us Thu, 27 Aug 2026 18:25:07 GMT https://securitybyfaisal.com/writing/sase-migration-multisite-retail-architecture/ https://securitybyfaisal.com/writing/sase-migration-multisite-retail-architecture/ An end-to-end architecture breakdown for migrating a multi-hundred-site retail network from MPLS/hub-and-spoke to SD-WAN + SASE, including the sequencing decisions that matter more than the vendor choice. Mon, 10 Aug 2026 00:00:00 GMT https://securitybyfaisal.com/writing/segmentation-gap-retail-sdwan-rfps/ https://securitybyfaisal.com/writing/segmentation-gap-retail-sdwan-rfps/ Across large multi-site retail transformations, the same segmentation gap keeps showing up between the network design and how PCI/PoS traffic actually gets isolated. Here's the pattern and what closes it. Tue, 28 Jul 2026 00:00:00 GMT https://securitybyfaisal.com/writing/rethinking-the-presales-security-architect-role/ https://securitybyfaisal.com/writing/rethinking-the-presales-security-architect-role/ Presales architects are trained to stay neutral between vendors. That habit quietly costs clients good security outcomes — here's where the line actually belongs. Tue, 14 Jul 2026 00:00:00 GMT