The Security Implications of Tethering a Mobile Phone To Your Computer

The ability to tether a mobile phone to a computer has allowed for much more flexible ways of using the Internet. Whether connected by USB cables, Bluetooth, or Wi-Fi networks, tethered connections enable 3G and 4G cellular networks to be joined onto a core laptop or desktop. Most of these connections rely on a mixture of networks that are either provided by cell phone companies and Internet Service Providers.

These companies often charge an additional fee for tethering devices, or require a user to have a phone contract in order to access mobile hotspots when on the move.

This convergence of mobile and fixed connections has developed out of improvements in 3G networks. Better packet switching, and faster downloads have improved connections, while smartphones and tablets have begun to take over from laptops as a primary device for some users.

Emerging 4G networks, which rely on a range of technologies, also demonstrate that a large portion of Internet users are now going online through their portable devices, with expectations of faster speeds and higher download limits. However, there are serious security risks for tethering mobile devices to fixed broadband networks.

Problems and Risks

The most basic problem with connecting different devices to a computer and a network is the lack of an equal level of encryption security. The more networks and devices you have, the more chance there is of signals being illegally intercepted in transmission. Risks here include Denial of Service attacks, and virus threats to both core and mobile networks. Mobile phones that connect to Wi Fi and fixed computer networks through Bluetooth have also had problems in the past with their GPS chips being illegally activated.

Broadband security problems consequently break down to a higher risk for hacking. This risk applies to both individual users who connect to different networks with inconsistent security features, and businesses that use tethering. A hacker could potentially bypass a central corporate network through an unsecured mobile connection. Other problems have arisen around jailbroken smartphones, which tend to lack the same levels of encryption as other devices.

Some Solutions

The only practical way to improve security for tethering is to increase encryption on both ends of a network. Software like MAPSec, or Mobile Application Part Security, has recently offered better encryption at the mobile end. Moreover, phone carriers are doing more to improve their 3G and 4G networks by adding software like McAfee. Users should also consider applying the same security approaches to their mobile or portable devices as they would to their desktops and laptops.

Vigilance on malware and website security is essential for mobiles, while users should be careful about transmitting information. Passwords for all networks should be difficult to crack, while WiFi networks should have the most up to date WPA2 encryption. More generally, using cables to connect devices is safer than wireless connections.

It is also likely that the next few years will see improved policing and packaging of tethered connections from providers. A key part of this change should involve providers lowering their tethering charges and usage limits to stop people from illegally hacking into connections, or from using jailbroken smartphones.

Sebastian is a full-time security analyst at leading blue chip corporation. He’s currently writing for one of the best independent broadband comparison websites in the UK – Cable.co.uk.