Most Popular UDP Ports

1. 631 (IPP) - Internet Printing Protocol
2. 161 (SNMP) - Simple Network Management Protocol
3. 137 (NETBIOS-NS) - Windows Services
4. 123 (NTP) - Network Time Protocol
5. 138 (NETBIOS-DGM) - Another Windows Services port
6. 1434 (MS-SQL-DS) - Microsoft SQL Server
7. 445 (Microsoft-DS) - Another Windows Services port
8. 135 (MSRPC) - MS Remote Procedure Call Services
9. 67 (DHCPS) - Dynamic Host Configuration Protocol Server
10. 53 (DNS) - Domain Name System server
11. 139 (NETBIOS-SSN) - Another Windows Services port
12. 500 (ISAKMP) - Internet Security Association and Key Management Protocol (IPsec VPNs)
13. 68 (DHCPC) - Dynamic Host Configuration Protocol Client
14. 520 (RIP) - Routing Information Protocol
15. 1900 (UPNP) - Microsoft Simple Service Discovery Protocol, which enables discovery of Universal Plug-and-Play devices
16. 4500 (NAT-T-IKE) - Network Address Translation Traversal while initiating IPsec connection (during Internet Key Exchange)
17. 514 (Syslog) - Standard UNIX log daemon
18. 49152 (Var) - First of the IANA-specified dynamic/private ports. No official ports may be registered from her to 65536.
19. 162 (SNMPTrap) - Simple Network Management Protocol trap port (SNMP agent uses 161 / SNMP manager uses 162)
20. 69 (TFTP) - Trivial File Transfer Protocol