The Foscam FI9821EP has a better interface than most similar spec webcams that have been around for around the same time as it. This Foscam webcam has an RJ-45 interface, whereas most webcams that have been on the market for around the same time as it have a Wi-Fi interface.
This webcam's interface (RJ-45) is in fact the worst interface across all similar spec webcams that have been available for around the same time as the FI9821EP.
The best interface amongst comparable types of webcam is USB 3.
Webcams with a better interface that might be worth considering include the SNH-V6110BN (£64.99) (Wi-Fi), or the VG-STC5000 (£109.00) (USB 2.0) both from Samsung or the Digitus DN-16047 (£67.97) (Wi-Fi).