As TFA points out, Macs have a built in service for caching content downloaded from Apple's various servers that can be turned on in the sharing tab of the cont

As TFA points out, Macs have a built in service for caching content downloaded from Apple's various servers that can be turned on in the sharing tab of the control panel on the Mac you would like to adopt this role. The other Macs and iDevices on your network will detect the caching server and start using it instead of overloading your WAN link every time a large file like a new OS version or OS update needs to be distributed. Encryption would interfere with caching. More information on content caching: https://www.idownloadblog.com/2018/07/17/howto-mac-content-caching/ https://www.idownloadblog.com/2018/07/17/howto-mac-content-c...