Can Public Safety and Commercial Traffic Co-Exist on LTE?

According to some experts, the answer is "No", at least given the way LTE sessions are currently established. This conclusion is based on the following:

  1. In order to make a call (or get onto the network), the device must send a request for access to the network
  2. The signaling channel input is located at each cell site
  3. If the number of requests for service exceeds the capacity on the signaling channel, some of the requests will not be processed

In other words, if the LTE signaling channel is congested, the level of priority makes no difference. If the cell site does not receive the request for service, it cannot be processed. So in reality, there is no true pre-emption in LTE today.

This also raises the question of deliberate attacks on the network. As was recently seen with Denial of Service (DoS) attacks, where computers were programmed to flood a PSAP with bogus phone calls effectively blocking legitimate calls from getting through, could a similar attack on a cell site have the same effect?

For the original Urgent Communications article by Andrew Seybold, click here.