would optical modem block the pptp connectivity?

[mathabstrction]

would optical modem block the pptp data transfer and connectivity?
probbaly thiere is a firewall inside the optical modem.
i am in China. and i found several chinese discussions in forums asserting that onu device will block pptp connectivity by default configuration in several webpages

[krinn]

If the device was doing it, hacking it or using another device would bypass it.
So without knowing, it looks logic your country put restrictions on providers.
You could try a solution like openvpn.