I'm not an application developer - Ill start off with that caveat.
In Brief; our development team have asked for me to open a series of ports from WAN to LAN completely bypassing our DMZ. They say this is fine because their api secures the connection first from two webservers in the DMZ (using diffie helman but that's another story) but were a little unsure that having open ports from WAN to LAN can ever be secure - can anyone enlighten me on the viability of this from a security standpoint?
Should not the end user always communicate to the DMZ and then a server within this do all the communication to any internal servers?