POS Network Cheatsheet
POS Network Cheatsheet
IP addressing, printer config, and card terminal network requirements.
IP Addressing
| Static IP | Assign manually on the device ߀” required for printers and card terminals |
| DHCP reservation | Router assigns fixed IP by MAC address ߀” easier to manage than manual statics |
| Printer self-test | Hold Feed while powering on ߀” prints current IP address |
| Printer web UI | Open printer IP in a browser to set static IP, subnet, gateway |
Card Terminal Requirements
| Port 443 outbound (HTTPS) | Must be open to payment processor ߀” never block this |
| DNS resolution | Terminal must resolve hostnames; use a reliable DNS (8.8.8.8 or router) |
| No HTTP proxy | Most terminals do not support proxy authentication |
| Wired Ethernet | Always prefer Ethernet over Wi-Fi for card terminals ߀” avoids drop-outs mid-transaction |
| Separate VLAN | PCI DSS requires card terminals isolated from general office network |
Remote Access
| TeamViewer / AnyDesk | Common for Windows POS ߀” vendor connects for remote support |
| VPN + RDP | More secure ߀” IT connects via VPN tunnel then RDP to terminal |
| DDNS | Dynamic DNS maps a hostname to a changing public IP when static IP unavailable |
| Static public IP | Required if the support vendor connects to the site directly |