Explanation/Reference:
Transport Control Protocol (TCP), User Datagram Protocol (UDP) ports, and Protocol Numbers are important to TCP/IP networking, intranets, and the Internet. Ports and protocol numbers provide access to a host computer. However, they also create a security hazard by allowing uninvited access. Therefore, knowing which port to allow or disable increases a network's security. If the wrong ports or protocol numbers are disabled on a firewall, router, or proxy server as a security measure, essential services might become unavailable.
Port 443 is used for Audio, video and application sharing sessions as well as data sharing sessions - For HTTPS.
Port 5223 is used for mobile push notifications - Extensible Messaging and Presence Protocol (XMPP) client connection over SSL.