Port 1998Cisco XOT
Cisco XOT (X.25 over TCP) facilitates the encapsulation of legacy X.25 traffic within TCP/IP networks, enabling organizations to transition smoothly from traditional X.25 infrastructure to modern IP-based networking without replacing existing applications. It supports both TCP and UDP for flexible transport options..
- transport
- tcp · udp
- in transit
- cleartext
- assignment
- official
- risk
- 4/10
- lookups
- 6,844
2 transports registered
payload readable on path
registered with iana
caution
rank 747 of 993 · top 75%
Technical Details
what runs on :1998Overview:
Cisco X.25 over TCP (XOT) is a protocol developed to encapsulate X.25 packets within TCP connections. This allows organizations to maintain their legacy X.25 applications and devices over contemporary IP network infrastructures. Since X.25 was widely used for WAN connectivity due to its reliable packet-switching capabilities, XOT provides a critical bridge for modernization.
Functionality:
In operation, XOT encapsulates LAPB frames (X.25 layer 2) into TCP segments, transmitting over standard IP networks. This substitute for physical X.25 links reduces the reliance on expensive leased lines or dedicated X.25 networks. It can operate over both TCP and UDP, although TCP is more commonly used due to its connection-oriented nature complementing X.25's requirements.
Deployment:
XOT is primarily found on Cisco networking equipment and is a key part of migration strategies where legacy financial, industrial, or telemetry systems still rely on X.25 protocols. It is supported on Cisco IOS platforms and can interoperate with X.25 DTE and DCE devices deployed in banks, ATMs, payment terminals, and traditional telemetry systems.
Security Information
exposure of :1998risk score
4/ 10caution
worth attention. how exposed you are depends on configuration — don't leave it reachable from the internet without a reason.
network services averages 3.9 across 604 ports — this one sits 0.1 above.
in transit
cleartext
credentials and payloads are readable by anyone on path
assignment
official
registered with iana for this service — scanners fingerprint it by number
reachable over
tcp · udp
udp is connectionless — source addresses are trivially spoofed and it is a reflection favourite
security overview
Common Vulnerabilities:
- Lack of encryption exposes sensitive data traversing the network
- Susceptible to man-in-the-middle attacks if routed over insecure networks
- Potential misuse in traffic tunneling or to bypass security controls
- Vulnerability to TCP-based attacks such as session hijacking or denial of service
- Legacy protocol weaknesses that can be exploited if transported without additional security
Common Mitigations:
- Employ IPsec or VPN tunnels to encrypt XOT sessions
- Restrict XOT communication to trusted, internal network segments
- Implement access control lists and firewall rules to limit unauthorized access
- Use network segmentation to isolate legacy protocol traffic
- Monitor XOT sessions for unusual patterns or unauthorized attempts
- Plan migration strategies to replace legacy X.25 applications with modern, secure alternatives over time
Related Ports
the 8 most looked-up other ports in network services — 604 ports carry that label.
| port | service | risk | |||
|---|---|---|---|---|---|
| :9080 | Groove RPC | TCPUDP | Web Services | caution | 70.8k |
| :6543 | Jetnet | UDP | Network Services | caution | 65.3k |
| :5938 | TeamViewer | TCPUDP | Remote Access | caution | 65.0k |
| :8291 | Winbox MikroTik Admin | TCP | Security | caution | 62.9k |
| :3233 | WhiskerControl Protocol | TCPUDP | Network Services | caution | 61.9k |
| :3268 | Microsoft Global Catalog (GC) | TCPUDP | Security | caution | 54.6k |
| :135 | Microsoft EPMAP | TCPUDP | Security | caution | 51.9k |
| :3128 | Tatsoft Default HTTP Proxy | TCP | Web Services | caution | 46.8k |
risk mix of the 8 listed
- caution100%
0 of 8 encrypted