I know that I can set up a local certification authority for a local network. I can issue certificates for all the devices in my network, and as long as they trust me, they can use such certificates to authenticate each other. External devices, instead, do not trust me, and so they cannot accept the certificates provided by my internal devices.
My question is
if my local certification authority would be provided with a certificate issued by an internationally trusted CA, external devices would be able to reconstruct the certificate chain and so, in the end, accept the certificates I issued as valid?