Determining the Services Running on a Network Alexander Rocco Corporation has multiple OSs running in its many branch offices. Before conducting a penetration test to determine the network’s vulnerabilities, you must analyze the services currently running on the network. Bob Kaikea, a member of your security team who’s experienced in programming and database design but weak in networking concepts, wants to be briefed on network topology issues at Alexander Rocco Corporation. Write a memo to Bob summarizing port numbers and services that run on most networks. The memo should discuss the concepts of well-known ports and give a brief description of the most commonly used ports: 20, 21, 23, 25, 53, and 110.