Links

Initial access (protocols)

Theory

Practice

Well known ports

Common port
Protocol
Description
21/TCP
FTP
22/TCP
SSH
23/TCP
Telnet
53/UDP or 53/TCP
DNS
80/TCP
HTTP
88/TCP
Kerberos
389/TCP
LDAP
443/TCP
HTTPS
445/TCP
SMB
554/TCP
RTSP
1433/TCP
MSSQL
2049/TCP
NFS
3306/TCP
MySQL
3389/TCP
RDP
5585/TCP or 5586/TCP
WinRM