Port 60 has no assigned service. No protocol runs here. No RFC defines it. In the IANA Service Name and Transport Protocol Port Number Registry, port 60 is listed as "Unassigned" for both TCP and UDP.1
That is the fact. But the reason port 60 is empty tells you something about how the Internet was built.
A Well-Known Port with Nothing to Say
Port 60 sits in the well-known range (0–1023), the most privileged address space in networking. On Unix-like systems, binding to any port in this range requires superuser privileges.2 These numbers were meant for the Internet's most important services: HTTP on 80, SMTP on 25, DNS on 53.
Port 60 got no such assignment. It has remained unassigned across every revision of the IANA port registry, from the earliest "Assigned Numbers" RFCs to the present day.
Why Port 60 Was Never Assigned
The answer lives in the ARPANET's original networking protocol: NCP, the Network Control Protocol.
NCP used simplex connections. Data flowed in one direction per socket. To have a two-way conversation, you needed two sockets: an odd-numbered socket for sending, an even-numbered socket for receiving.3
Jon Postel's RFC 349, published in May 1972, proposed the first standard socket number assignments. Every assigned service got an odd number: Telnet on socket 1, File Transfer on socket 3, Remote Job Entry on socket 5, Echo on socket 7.4 The even-numbered sockets were structurally reserved as receive-side partners.
Port 59 was assigned to "any private file service."5 Port 60 would have been its receiving counterpart under NCP's pairing model.
On January 1, 1983, the ARPANET switched from NCP to TCP/IP.3 TCP connections are full-duplex: both sides send and receive on the same port. The even-numbered partners lost their structural purpose overnight. Some even-numbered ports eventually received new assignments as the Internet grew. Port 60 never did.
No Known Unofficial Uses
Unlike some unassigned ports that have been adopted by applications or targeted by malware, port 60 has no commonly documented unofficial uses. Security databases show no known trojan or malware associations.6
This makes port 60 genuinely quiet. Not exploited. Not repurposed. Just empty.
How to Check What Is Listening on Port 60
If you want to verify nothing unexpected is using port 60 on your system:
Linux:
macOS:
Windows:
If any process is listening on port 60, investigate it. There is no legitimate standard service assigned to this port.
Why Unassigned Ports Matter
The well-known port range contains 1,024 numbers. Not all of them need assignments. The unassigned ones serve a purpose: they are the negative space in the system, the proof that port assignments were deliberate rather than arbitrary. Every empty slot is a slot that was not wasted on a protocol that did not earn its place.
Port 60 is one of several even-numbered ports in the low range that trace their emptiness back to the NCP era. They are fossils of a design decision that predates the Internet itself, quiet reminders that the infrastructure we depend on was built in layers, each one replacing the last, not always cleaning up after itself.
Frequently Asked Questions
Was this page helpful?