Port 18634Reliable Datagram Service over InfiniBand (RDS/IB)

RDS/IB is a specialized reliable-datagram transport for Linux cluster traffic over RDMA/InfiniBand, not a typical public Internet service.

inNetwork Services

transport: tcp · udp
in transit: cleartext
assignment: official
risk: 2/10
lookups: 0

also known as rds-ib, RDS

Technical Details

what runs on :18634

RDS is a message-oriented Linux socket protocol designed for reliable, low-latency datagrams; its InfiniBand transport uses RDMA rather than behaving like an ordinary TCP application. IANA lists port 18634 for TCP and UDP under this service name, but that registration does not mean a conventional TCP or UDP listener will be present: actual RDS/IB deployments depend on the kernel RDS/RDMA stack and an RDMA-capable fabric. The port is chiefly relevant when identifying or filtering specialized cluster traffic.

Security Information

exposure of :18634

risk score

2/ 10safe

routine exposure. this port is rarely the way in on its own — keep it patched and logged and move on.

network services averages 2.6 across 1,925 ports — this one sits 0.6 below.

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

RDS/IB is generally intended for a trusted cluster or RDMA fabric, not direct exposure to the public Internet. It is not encrypted by default; restrict access to the relevant cluster interfaces and peers, and do not infer that an open port is a normal public service.

Record

iana registry entry

port: :18634
service: Reliable Datagram Service over InfiniBand (RDS/IB)
transport: TCPUDP
encryption: cleartext
assignment: iana registered
risk: 2/10safe
category: Network Services
usage: RDS/IB is associated with Linux Reliable Datagram Sockets deployments, including some Oracle cluster environments using InfiniBand or RDMA. It is a specialized fabric-side service, not a commonly encountered Internet-facing listener.
lookups: 0rank 993
added: 2026-10-18
updated: 2026-10-18
references: IANA service name registry — port 18634

Something wrong?

This record is maintained by the engineers who use port 18634. Every field on it is editable — change what's wrong, say how you know, and a reviewer publishes it, usually within a minute. Last touched 2026-10-18.

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edit this record →back to the registry

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risk mix of the 8 listed

caution100%

0 of 8 encrypted

Port :18634Reliable Datagram Service over InfiniBand (RDS/IB)

Technical Details

Security Information

Related Ports

Port 18634Reliable Datagram Service over InfiniBand (RDS/IB)