TCP / UDP PORTS
137, 138,139 Server Message Block (SMB) over NetBIOS
NetbIoS is a legacy suite of protocols used by windows before TCp/IP. to support legacy NetBIOS applications on a TCP/IP network, TCP offers NetbIoS over TCP/IP. earlier versions of Smb required NetbIoS over TCP/IP be enabled. ports used on these networks are: SMB over UDP uses ports 137 and 138. SMB over TCP uses ports 137 and 139. Current versions of Smb don't require NetbIoS over tCp.
3389 Remote Desktop Protocol (RDP) apps, including Remote Desktop and Remote Assistance
Remote Desktop and Remote Assistance listen at port 3389
20 File Transfer Protocol (FTP) Client
The File Transfer Protocol (FTP) Client receives data on port 20 from the FTP server
21File Transfer Protocol ( FTP) Server
The File Transfer Protocol (FTP) server listens on port 21 for commands from an FTP client
143 Internet Message Access Protocol (IMAP) email client
An email client using IMAP receives email at port 143
110 Post Office Protocol, version 3 (POP3) email client
An email client using POP3 receives email at port 110
23 Telnet Server
A Telnet server listens at port 23
22 Secure Shell (SSH) Server
A server using the Secure Shell (SSH) protocol listens at port 22
443 Web server using Hypertext Transfer Protocol (HTTP)
A web server listens at port 443 when receiving HTTPS transmissions
80 Web server using Hypertext Transfer Protocol (HTTP)
A web server listens at port 80 when receiving HTTP transmissions
548 Apple Filing Protocol (AFP)
AFP over TCP/IP is used for file sharing and file services
445 Server Message Block (SMB) direct over Transmission Control Protocol (TCP)/Internet Protocol (IP)
Current releases of SMB and SMB2 use port 445 for both TCP and User Datagram Protocol (UDP) traffic
53 Domain Name Server or Domain Name Service (DNS)Server
Domain Name Server or Domain Name Service (DNS) A DNS server listens at port 53
427 Service Location Protocol (SLP) and Apple Filing Protocol (AFP)
Service Location Protocol (SLP) uses port 427 to find printers and file sharing devices on a network. AFP relies on SLP and port 427 to find resources on a local network
25 Simple Mail Transfer Protocol (SMTP) email server
Simple Mail Transfer Protocol (SMTP) An email server listens at port 25 to receive email from a client computer