4500
IPsec NAT Traversal
Low RiskUDP — Security & VPN
Port Overview
Port Number
4500
Service Name
IPsec NAT Traversal
Transport Protocol
UDP
Category
Security & VPN
Security Risk
Low
Port Range
Registered (1024-49151)
What is Port 4500?
Port 4500 is used for IPsec NAT traversal (NAT-T), which encapsulates IKE and ESP packets inside UDP to traverse NAT devices. VPN clients and servers use this port when standard IPsec on port 500 cannot traverse NAT. It is essential for IKEv2/IPsec VPN connections through NAT firewalls.
UDP
Security & VPN
Commonly Used
Security Considerations
Port 4500 (IPsec NAT Traversal) is classified as low risk. This service uses encryption or has a minimal attack surface, making it relatively safe to expose.
Recommendation: Standard security practices apply. Keep software updated and monitor access.