Local Brew is a small cafe operating in New York. It has set up a free wireless network in its cafe to provide customers with ease of Internet access. Recently, one of the customers lodged a complaint against Local Brew regarding data theft from his emails, which has been traced back to the cafe's public IP$.$ Local Brew has informed Barton, who is the network provider for the cafe, to rectify the issue. Which of the following should Barton do to analyze and rectify the issue?