Carriers have the ability to detect tethering by analyzing the data traffic that passes through their network. Tethering involves using the cellular data of a smartphone or tablet to provide internet connectivity to another device such as a laptop or desktop computer. This can result in higher data usage than what would be expected from just using a smartphone or tablet alone. Carriers can identify this type of data traffic and may apply additional charges or throttle the connection depending on the specific terms of the customer's data plan. However, there are ways to bypass carrier detection of tethering such as using a VPN or third-party app. It's important to note that bypassing tethering restrictions may be a violation of terms of service with the carrier and could result in consequences such as termination of service.