183

Port 183/tcp is an IANA System Port registered under the service name ocbinder with the bare description "OCBinder." The registration is dual — 183/udp carries the identical service name and description — but beyond that the IANA record is essentially empty: no assignee, no contact, no registration or modification date, and no RFC or other reference are recorded in either the live IANA registry (txt/xhtml views) or the locally cached CSV snapshot used for cross-checking. This blank-metadata pattern is typical of an old, minimal-effort System Port assignment rather than a documented, actively maintained protocol. No independent primary source — vendor documentation, an RFC, or a technical specification — could be located describing what "OCBinder" actually is or what software implements it; every secondary port-lookup aggregator found (SpeedGuide-style sites, adminsub.net, windows9download) simply repeats the same IANA name and description without adding technical detail, so none of them count as independent corroboration. One low-authority historical aggregator (auditmypc.com) notes no recorded virus/Trojan association for TCP 183, but that is a single weak secondary source, not a security-vendor advisory. No data on real-world prevalence, exposure, or scanning activity for this specific port was found. Given the absence of a protocol description, implementing software, or usage evidence, this entry should be treated as a legacy/dormant IANA registration of unknown real-world significance rather than a documented, currently-used service.

IANA assignment

ocbinder — "OCBinder"; reference (blank — no RFC/reference recorded); assignee/contact Unknown (blank in registry); dual-registered 183/tcp + 183/udp under the same name [Confirmed] — https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.txt

Range class

well-known (0–1023)

Registration/modification dates

Unknown — both fields blank in the IANA registry; not fabricated [Confirmed] — https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.txt

Prevalence

Unknown — no nmap-services or scanning-frequency data located for this entry in current research [Unknown]

Related ports

no directly related cluster identified; contrast with other minimally-documented legacy System Ports in the same range

Primary use / protocol purpose

Unknown — no primary-source specification, RFC, or vendor documentation identified describing the OCBinder protocol beyond the bare IANA label

Common software

Unknown/Unconfirmed — no vendor or software project identified as currently using this port; appears to be a dormant/legacy System Port assignment [Unknown]

Security implications

No confirmed malware or CVE association found; one weak secondary source (auditmypc.com) reports no historical virus/Trojan flag for TCP 183, but this is unconfirmed/low-authority and not treated as authoritative

Typically seen on

Unknown — no evidence of active deployment identified; if seen open, treat as anomalous/unexplained rather than a recognized service [Unknown]

Port 183/udp is registered with IANA under the service name ocbinder, with only the bare description "OCBinder" — the registry's Assignee, Contact, Registration Date, Modification Date, Reference, Service Code, Unauthorized Use Reported, and Assignment Notes columns are all blank for this entry, a common footprint among older, sparsely-documented Service Name and Transport Protocol Port Number Registry rows. Port 183 is dual-registered: the matching 183/tcp row carries the identical service name and description with the same blank metadata, so both transports point to the same nominal service. Beyond the two-word IANA label, no further authoritative specification, vendor documentation, RFC, or software product describing what "OCBinder" actually implements could be located. It should not be confused with OpenBinder, the unrelated Be Inc./PalmSource inter-process-communication framework that predates Android's Binder IPC mechanism — the names are superficially similar but there is no connection to port 183 in any source found. A handful of low-quality port-scanning aggregator sites carry generic malware/Trojan association disclaimers, but these read as boilerplate applied broadly across their catalogs rather than sourced incident reports, so they are not treated as verified findings here. In practice, port 183 sits in the well-known range (0–1023) and, given the total absence of documented real-world usage, should be treated as a legacy or largely-dormant IANA registration rather than an actively deployed service.

IANA assignment (udp)

service name ocbinder; description "OCBinder"; Reference field blank (no RFC cited) [Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry (row 453); cross-checked against https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.txt

Dual registration

183/tcp carries the identical service name/description with the same blank metadata (row 452 of the same registry file) [Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry; https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.txt

Range class

well-known (0–1023) [Confirmed]

Assignment/registration date

Unknown — IANA registry publishes no date for this legacy entry; not invented [Unknown]

Common software / real-world deployment

Unknown — no identified product or implementation found using this port under this name [Unknown]

Exposure/scanning notes

low-confidence — aggregator sites (e.g. auditmypc.com) show generic boilerplate Trojan-association disclaimers applied broadly across their catalog, not a sourced incident; not treated as a verified malware association

Assignee / Contact / Registration date / Modification date / Service code / Unauthorized use reported / Assignment notes

all blank in the registry source — not fabricated [Confirmed] — the IANA Service Name and Transport Protocol Port Number Registry

Primary protocol use

Unknown — no authoritative spec, vendor documentation, or RFC describing what the OCBinder service implements beyond the bare IANA name [Unknown] — https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.txt

Disambiguation

not the same as "OpenBinder," the unrelated Be Inc./PalmSource IPC framework and ancestor of Android Binder — no connection to port 183 [Confirmed] — https://en.wikipedia.org/wiki/OpenBinder