Common Ports (50)
Well-known TCP/UDP port numbers for Network+ study
| Port | Protocol | Service | Description |
|---|---|---|---|
| 20 | TCP | FTP-DATA | FTP active mode data channel |
| 21 | TCP | FTP | FTP control (commands) |
| 22 | TCP | SSH | Secure shell remote login |
| 23 | TCP | Telnet | Unencrypted terminal (legacy) |
| 25 | TCP | SMTP | Simple Mail Transfer Protocol |
| 49 | TCP | TACACS+ | Cisco AAA (legacy TACACS) |
| 53 | TCP/UDP | DNS | Domain Name System queries |
| 67 | UDP | DHCP server | Bootstrap Protocol / DHCP server |
| 68 | UDP | DHCP client | DHCP client |
| 69 | UDP | TFTP | Trivial File Transfer Protocol |
| 80 | TCP | HTTP | Hypertext Transfer Protocol |
| 110 | TCP | POP3 | Post Office Protocol v3 |
| 119 | TCP | NNTP | Network News Transfer Protocol |
| 123 | UDP | NTP | Network Time Protocol |
| 135 | TCP/UDP | MS RPC | Microsoft RPC endpoint mapper |
| 137 | UDP | NetBIOS-NS | NetBIOS name service |
| 138 | UDP | NetBIOS-DGM | NetBIOS datagram service |
| 139 | TCP | NetBIOS-SSN | NetBIOS session (SMB legacy) |
| 143 | TCP | IMAP | Internet Message Access Protocol |
| 161 | UDP | SNMP | Simple Network Management Protocol |
| 162 | UDP | SNMP trap | SNMP notifications to manager |
| 179 | TCP | BGP | Border Gateway Protocol |
| 389 | TCP/UDP | LDAP | Lightweight Directory Access Protocol |
| 443 | TCP | HTTPS | HTTP over TLS |
| 445 | TCP | SMB | Server Message Block over TCP |
| 464 | TCP/UDP | Kerberos | Kerberos password change |
| 465 | TCP | SMTPS | SMTP over TLS (legacy) |
| 514 | UDP | Syslog | Syslog (legacy UDP) |
| 587 | TCP | SMTP submission | Mail submission (STARTTLS) |
| 636 | TCP | LDAPS | LDAP over TLS |
| 993 | TCP | IMAPS | IMAP over TLS |
| 995 | TCP | POP3S | POP3 over TLS |
| 1433 | TCP | MSSQL | Microsoft SQL Server |
| 1521 | TCP | Oracle | Oracle database listener |
| 1723 | TCP | PPTP | Point-to-Point Tunneling Protocol |
| 2049 | TCP/UDP | NFS | Network File System |
| 2083 | TCP | cPanel SSL | cPanel HTTPS (typical) |
| 3306 | TCP | MySQL | MySQL / MariaDB default |
| 3389 | TCP | RDP | Remote Desktop Protocol |
| 5060 | TCP/UDP | SIP | Session Initiation Protocol |
| 5061 | TCP | SIP-TLS | SIP over TLS |
| 5432 | TCP | PostgreSQL | PostgreSQL default |
| 5900 | TCP | VNC | RFB / VNC display :0 |
| 5985 | TCP | WinRM HTTP | Windows Remote Management |
| 5986 | TCP | WinRM HTTPS | WinRM over TLS |
| 6379 | TCP | Redis | Redis in-memory datastore |
| 8080 | TCP | HTTP-alt | Alternate HTTP (proxies, Tomcat) |
| 8443 | TCP | HTTPS-alt | Alternate HTTPS (common in apps) |
| 11211 | TCP/UDP | Memcached | Memcached caching |
| 27017 | TCP | MongoDB | MongoDB default |
Network+ exam tipNetwork+ requires knowing at minimum: 20/21 FTP, 22 SSH, 23 Telnet, 25 SMTP, 53 DNS, 67/68 DHCP, 80 HTTP, 110 POP3, 143 IMAP, 443 HTTPS, 3389 RDP, 161/162 SNMP.