If you use the right router configured properly then it can provide increased security and speed, not to mention additional features like VPN tunnels or guest wifi access.
If you are just throwing a cheap router in between your laptop and CT modem, LAN to WAN port on the router, then no. Infact, you’re probably just slowing things down and creating potential network issues by running all the traffic through NAT twice. You’ll need to get China Telecom to reconfigure the modem to bridge mode – this can be done remotely.
Alternatively, you could just use the router as an access point by turning NAT and DHCP off then connecting it LAN to LAN. This might provide some benefits depending on the router.
If none of that is of any interest or makes any sense then you should just remove the router and make sure the CT modem/router uses WPA2/AES encryption under wifi settings and set a secure password.
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