##

Well-Known Ports & Protocols

Ports 0–1023 are well-known. These are the ones that come up in firewalls, ACLs, and exams.

0 – 1023

Well-known

1024 – 49151

Registered

49152 – 65535

Dynamic / ephemeral

20/21

FTP (data / control)

TCP

22

SSH / SCP / SFTP

TCP

23

Telnet

TCP

25

SMTP

TCP

49

TACACS+

TCP/UDP

53

DNS

UDP/TCP

67/68

DHCP (server / client)

UDP

69

TFTP

UDP

80

HTTP

TCP

88

Kerberos

TCP/UDP

110

POP3

TCP

119

NNTP

TCP

123

NTP

UDP

137/139

NetBIOS

TCP/UDP

143

IMAP

TCP

161/162

SNMP (agent / trap)

UDP

179

BGP

TCP

389

LDAP

TCP/UDP

443

HTTPS / TLS

TCP

445

SMB / CIFS

TCP

465/587

SMTP over TLS

TCP

500

IKE / IPsec

UDP

514

Syslog

UDP

520

RIP

UDP

546/547

DHCPv6

UDP

636

LDAPS

TCP

646

MPLS LDP

TCP/UDP

853

DNS over TLS

TCP

990

FTPS

TCP

993

IMAPS

TCP

995

POP3S

TCP

1194

OpenVPN

UDP

1433

MS SQL Server

TCP

1701

L2TP

UDP

1723

PPTP

TCP

1812/1813

RADIUS (auth / acct)

UDP

2049

NFS

TCP/UDP

3260

iSCSI

TCP

3306

MySQL / MariaDB

TCP

3389

RDP

TCP

4500

IPsec NAT-T

UDP

5060/5061

SIP

UDP/TCP

5432

PostgreSQL

TCP

5900

VNC

TCP

5985/5986

WinRM

TCP

6379

Redis

TCP

8080

HTTP alt / proxy

TCP

8443

HTTPS alt

TCP

27017

MongoDB

TCP