Nmap (Network Mapper) is a security scanner,used to discover hosts and services on a computer network, thus building a "map" of the network..
Understanding the results from the online Nmap scan will reveal whether a firewall is present. The shodan.io search engine finds millions of poorly configured firewalls on a daily basis.
Launch remote scans against your infrastructure to test that your security monitoring is working as expected. Review firewall logging and Intrusion Detection System alerts.
Your getting pushed to roll out the new service. The network guys are saying its not their problem, and the firewall administrator is pointing the finger at the developers. Sometimes you just need to know if the port is open and listening.