WAN interface responds as LAN when request comes from LAN, is that correct?

Question

I have a problem with my router/modem. I've published an HTTP service from one of my internal computers and when I access the service from the internal lan using the external IP address the modem responds instead of redirecting the call to the forwarded port. I can access the service from outside however, but from the internal network the modem responds to my calls. I'm using a ZTE ZXDSL 831 Series modem with ZXDSL 831IIV7.5.1e_E09_BR1 firmware.

Thanks in advance!

Answer 1

This is the expected behavior on some routers. Buffalo is another company that comes to mind that behaves this way. Apparently yours is another.