1998
Cisco X.25
Low RiskTCP — System & Infrastructure
Port Overview
Port Number
1998
Service Name
Cisco X.25
Transport Protocol
TCP
Category
System & Infrastructure
Security Risk
Low
Port Range
Registered (1024-49151)
What is Port 1998?
Port 1998 is used by Cisco for X.25 service access in IOS-based routers. X.25 is a legacy packet-switched WAN protocol that was widely used before Frame Relay and modern broadband. This port appears in legacy Cisco router configurations that still support X.25 connectivity.
TCP
System & Infrastructure
Security Considerations
Port 1998 (Cisco X.25) 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.