IANA lists at least one assignment on 22 of the 1,000 numbers from 18000 to 18999, 2.2%. The longest stretch with no assignment on any protocol runs from 18263 to 18462 (200 numbers). 4 numbers here are assigned on TCP alone and 1 on UDP alone. Of the 12 dated assignments, the earliest recorded date is July 2002 (ique on 18769); the latest is May 13, 2020, for heythings on 18516.
One square per number, 18000 at top left. Outlined squares have their own page.TCP and UDPTCP onlyUDP onlySCTP or DCCP onlyno assignment
Every assigned number from 18000 to 18999
18000–18099 · 1 number assigned
Port
Service
Protocols
Label
Registered
18000
biimenu
TCPUDP
Beckman Instruments, Inc.
—
18001–18099: no assignment, 99 numbers
18100–18199 · 9 numbers assigned
Port
Service
Protocols
Label
Registered
18104
radpdf
TCP
RAD PDF Service
Oct 15, 2010
18105–18135: no assignment, 31 numbers
18136
racf
TCP
z/OS Resource Access Control Facility
Oct 4, 2010
18137–18180: no assignment, 44 numbers
18181
opsec-cvp
TCPUDP
OPSEC CVP
—
18182
opsec-ufp
TCPUDP
OPSEC UFP
—
18183
opsec-sam
TCPUDP
OPSEC SAM
—
18184
opsec-lea
TCPUDP
OPSEC LEA
—
18185
opsec-omi
TCPUDP
OPSEC OMI
—
18186
ohsc
TCPUDP
Occupational Health SC
Aug 2003
18187
opsec-ela
TCPUDP
OPSEC ELA
—
18188–18199: no assignment, 12 numbers
18200–18299 · 4 numbers assigned
Port
Service
Protocols
Label
Registered
18200–18240: no assignment, 41 numbers
18241
checkpoint-rtm
TCPUDP
Check Point RTM
—
18242
iclid
TCP
Checkpoint router monitoring
Jun 28, 2012
18243
clusterxl
TCP
Checkpoint router state backup
Jun 28, 2012
18244–18261: no assignment, 18 numbers
18262
gv-pf
TCPUDP
GV NetConfig Service
Jan 29, 2008
18263–18299: no assignment, 37 numbers
18300–18399: no assignment, 100 numbers
18400–18499 · 1 number assigned
Port
Service
Protocols
Label
Registered
18400–18462: no assignment, 63 numbers
18463
ac-cluster
TCPUDP
AC Cluster
—
18464–18499: no assignment, 36 numbers
18500–18599 · 1 number assigned
Port
Service
Protocols
Label
Registered
18500–18515: no assignment, 16 numbers
18516
heythings
UDP
HeyThings Device communicate service
May 13, 2020
18517–18599: no assignment, 83 numbers
18600–18699 · 3 numbers assigned
Port
Service
Protocols
Label
Registered
18600–18633: no assignment, 34 numbers
18634
rds-ib
TCPUDP
Reliable Datagram Service
Feb 27, 2009
18635
rds-ip
TCPUDP
Reliable Datagram Service over IP
May 20, 2009
18636–18667: no assignment, 32 numbers
18668
vdmmesh vdmmesh-disc
TCPUDP
Manufacturing Execution Systems Mesh Communication Manufacturing Execution Systems Mesh Communication