Hi guys. I purchased 4 Zmodo wifi cameras ZP-IB15H-W. Here is my issue. I purchased these for an event to use for security. Where the event is taking place there is no internet. When I spoke to Zmodo they are telling me that you need internet to use the cameras but I find that hard to believe. Can you guys tell me if what I want to do is possible and if so what other devices do I need. Thanks in advance.