Web cache
This option is not available on the MX60, MX60W, MX64, MX64W, MX65, MX65W, MX67, MX67W, MX67C, MX68, MX68W, MX68CW, MX75, MX85, MX95, MX105, Z1, Z3, Z3C, Z4, Z4C devices.
When HTTP content caching is enabled, the MX will cache web content on its solid-state drive (SSD). This can improve end-user experience by reducing page load times and file download times for frequently accessed web content. Web caching only works for static HTTP content, so it will not be able to cache sites such as YouTube.
This feature is recommended only for sites with limited bandwidth. Locations with over 20 Mbps bandwidth will likely not benefit from content caching.
https://documentation.meraki.com/MX/Firewall_and_Traffic_Shaping/SD-WAN_and_Traffic_Shaping#Web_cach...
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
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