Net+ Ports and Protocols

File Transfer Protocol (FTP)

20/21

TCP

Secure Shell (SSH) | Secure File Transfer Protocol (SFTP) | Secure Copy

22

TCP

Telnet

23

Remote terminal access (insecure)

TCP

Simple Mail Transfer Protocol (SMTP)

25

Emails

TCP

Domain Name System (DNS)

53

Resolves domain names to IP addresses

TCP/UDP

Dynamic Host Configuration Protocol (DHCP)

67/68

67: server listens for client requests

68: client receive server replies

UDP

Trivial File Transfer Protocol (TFTP)

69

simple file transfer (less secure than FTP)

UDP

Hypertext Transfer Protocol (HTTP)

80

Websites

TCP

Network Time Protocol (NTP)

123

Synchronizes device clocks to Coordinated Universal Time (UTC) to prevent time drift and ensure uniform timestamps.

UDP

Simple Network Management Protocol (SNMP)

161

Monitoring & managing network devices

UDP

Lightweight Directory Access Protocol (LDAP)

389

Accessing AD

TCP

Hypertext Transfer Protocol Secure (HTTPS)

443

Secure web browsing (using SSL/ TLS encryption)

TCP

Server Message Block (SMB)

445

File & printer sharing in windows networks

TCP

Syslog

514

System logging and message forwarding

UDP

Simple Mail Transfer Protocol Secure (SMTPS)

465, 587

Secure email sending (using SSL/TLS encryption)

TCP

Lightweight Directory Access Protocol over SSL (LDAPS)

636

Directory service (using SSL/TLS encryption)

TCP

Structured Query Language (SQL) Server

1433

Microsoft SQL

Access Microsoft SQL Server Databases

TCP

Remote Desktop Protocol (RDP)

3389

Remotely control another computer

TCP

Session Initiation Protocol (SIP)

5060 / 5061

is an application-layer signaling protocol used to set up, maintain, modify, and end real-time communication sessions—such as voice calls, video conferences, and instant messaging—over IP networks

UDP

Kerberos

88

Authentication service

UDP

Post office protocol (POP3)

110

Receiving email

TCP

Network News Transfer Protocol (NNTP)

119

accessing news groups

TCP

Remote Procedure Call (RPC)

135

Programs communicate on a network

TCP/UDP

IMAP Internet Message Access Protocol (IMAP)

143

Receiving and managing email

TCP

Simple Network Management Protocol (SNMP)

161

Monitoring & managing network devices

UDP

Simple network management protocol trap (SNMP Trap)

162

sending traps (alerts) from network devices to an SNMP manager

UDP

Lightweight Directory Access Protocol (LDAP)

389

Active Directory services

TCP

Internet Message Access Protocol Secure (IMAPS)

993

IMAP over SSL/TLS (secure)

TCP

Post office Protocol Secure (POP3S)

995

Secure POP3 (SSL/TLS encryption)

TCP

RADIUS

1645, 1646

Remote Authentication

Network access authentication

TCP

RADIUS UDP

1812, 1813

Network access authentication UDP

UDP

Syslog TLS

6514

Secure System logging using TLS encryption

TCP

System/ Well Known Ports

0-1023

Registered / User Ports

1024 - 49515

Dynamic/ Private Ports

49152 – 65535