All these are wired system, not wireless. Complete system do not need Internet to work. However, an Internet will be necessary if you wish to use mobile for remote view. This is a variation listing, camera has 4 Bullet/8 Bullet/4 Bullet+4 Dome for option and hard drive has No HDD/1TB HDD/2TB HDD for option. Please choose the right one according to your needs. Plug & Play, Easy Setup Even for Beginners. Quick & Easy Connection. Download ZOSI Smart APP. Save Hard Disk Capacity. Lower Bandwidth, Fast Transmission Speed. Low Bite Rate, Higher Image Quality. Local and Remote Access in Multiple Devices. Local Access: Connect the system to a monitor or TV via the HDMI cable or VGA cable. Remote Access: (Also need to connect the system to internet) Easy to get live streaming or playback videos via ZOSI App on iOS & Android devices, through ZOSI Client software on Windows or Mac, or via major browsers. With self-adaptive technology, it supports 4 kinds of camera models:Analog, AHD, TVI and CVI. Support 1 SATA port, 1HDD of 2TB, 3 USB 2.0 port, 4 Audio input port, Support mouse control, USB Video Back up, DVR upgrade. Customizable Motion Detection Zones & Alert. ZOSI DVR security system allows you to customize the motion detection area in each camera, reducing the number of false alarms, and get motion clip alerts only when something happens there. Day & Night In 1080p Full HD. Day or night, the camera always protects your home with 1080p HD. The camera has 24 infrared LED lights, and the night vision distance can reach 80 feet, even at night, you can see the details clearly. Smart Motion Detection and Rich Alerts. Detect moving objects and trigger alerts when dangers occur. You will receive instant alerts in forms of emails, App push notifications and buzzer alarms in the DVR when invasion happens. You can also set up specific motion zones and adjust the sensitivity to reduce unnecessary false alarms. Customize Each Camera with Different Record Modes. ZOSI DVR offers 4 kinds recording modes to meet your needs: 24/7 Record ; Scheduled Record; Motion Detect Record; Recycle Record. You can customize each camera with different recording modes, which allows you to save space on the hard drive. You can have a good view of all cameras in real time at the front of the TV screen. Applied to Multiple Occasions.