82:
The allocation of an ephemeral port is temporary and only valid for the duration of the communication session. After completion of the session, the port is destroyed and the port number becomes available for reuse, but many implementations simply increment the last used port number until the
220:
If certain server software is used, that uses non-ephemeral custom port ranges for initiating some further connections, it needs to be ensured by configuration that this custom port range and the ephemeral port range do not overlap.
173:
default of
Windows Server 2008 with Exchange Server 2007 installed. In addition to the default range, all versions of Windows since Windows 2000 have the option of specifying a custom range anywhere within 1025–65535.
67:
end of the communication session, ephemeral ports may also be used for continuation of communications with a client that initially connected to one of the services listening with a
35:
that is used for only a short period of time for the duration of a communication session. Such short-lived ports are allocated automatically within a predefined range of
345:
Internet
Assigned Numbers Authority (IANA) Procedures for the Management of the Service Name and Transport Protocol Port Number Registry
52:
110:
497:
525:
note that the Linux 2.4 kernel will default the range of 32768 through 61000 if adequate kernel memory is available
235:
209:, until Microsoft security update MS08-037 from 2008 is installed, after which it uses the IANA range by default.
401:
349:
290:
186:
72:
44:
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150:
24:
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the
Dynamic Ports, also known as the Private or Ephemeral Ports, ... 49152-65535 (never assigned)
32:
154:
83:
ephemeral port range is exhausted, when the numbers roll over. Ephemeral ports are also called
48:
514:
87:, because they are used on a per request basis, and are only known by number once allocated.
76:
567:
536:
363:
304:
339:
8:
206:
64:
56:
493:
190:
60:
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UNIX Network
Programming, Volume 1, Second Edition: Networking APIs: Sockets and XTI
444:
However, ephemeral port selection algorithms should use the whole range 1024–65535.
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353:
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230:
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28:
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307:
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Cotton, M.; Eggert, L.; Touch, J.; Westerlund, M.; Cheshire, S. (August 2011).
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122:
40:
563:
RFC 6056 Recommendations for
Transport-Protocol Port Randomization
182:
114:
255:
337:
430:
Recommendations for
Transport-Protocol Port Randomization
16:
Short-lived transport protocol port for IP communications
416:
The default values are 32768 and 60999 respectively.
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427:
215:
117:has used the IANA port range since release 4.6.
282:
55:(SCTP) typically use an ephemeral port for the
432:. sec. 3.2. Ephemeral Port Number Range.
79:(RPC) applications can behave in this manner.
43:software of a computer operating system. The
512:
574:Ephemeral Source Port Selection Strategies
437:
357:
298:
492:. Prentice Hall. 1998. pp. 42–43.
582:
260:/proc/sys/net/ipv4/ip_local_port_range
254:The effective range is accessible via
113:(IANA) for dynamic or private ports.
53:Stream Control Transmission Protocol
428:M. Larsen; F. Gont (January 2011).
185:versions before 4.6, including the
111:Internet Assigned Numbers Authority
13:
14:
606:
556:
537:Microsoft Windows Technet Library
236:List of TCP and UDP port numbers
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530:
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129:use the IANA range by default.
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406:The Linux Kernel documentation
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331:
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286:The TFTP Protocol (Revision 2)
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187:Berkeley Software Distribution
109:suggested by RFC 6335 and the
73:Trivial File Transfer Protocol
23:is a communications endpoint (
1:
283:Karen R.Sollins (July 1992).
269:
216:Configuration characteristics
45:Transmission Control Protocol
327:IANA port number assignments
7:
548:Microsoft KB Article 956188
478:Microsoft KB Article 196271
467:Microsoft KB Article 929851
456:Microsoft KB Article 929851
390:Microsoft KB Article 929851
224:
10:
611:
515:"The Ephemeral Port Range"
193:operating systems through
568:The Ephemeral Port Range
241:
189:(BSD). Default range of
90:
33:Internet protocol suite
63:communication. At the
49:User Datagram Protocol
513:Mike Gleason (2001).
77:Remote Procedure Call
340:"Port Number Ranges"
207:Windows Server 2003
71:. For example, the
595:Internet protocols
590:Internet Standards
213:
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191:Microsoft Windows
101:Operating system
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576:at DataPlane.org
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359:10.17487/RFC6335
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300:10.17487/RFC1350
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31:protocol of the
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352:. sec. 6.
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231:Registered port
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69:well-known port
51:(UDP), and the
29:transport layer
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557:External links
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21:ephemeral port
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499:0-13-490012-X
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139:Linux kernels
137:used by many
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119:Windows Vista
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85:dynamic ports
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61:client–server
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570:at NcFTP.com
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518:. Retrieved
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409:. Retrieved
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372:November 14,
370:. Retrieved
344:
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322:
311:. Retrieved
285:
278:
250:
219:
84:
81:
37:port numbers
20:
18:
402:"IP Sysctl"
146:32768–65535
134:32768–60999
127:Server 2008
106:49152–65535
75:(TFTP) and
47:(TCP), the
584:Categories
520:2018-01-15
411:2021-06-27
313:2020-10-18
270:References
195:Windows XP
170:1025–60000
165:RFC 6056
162:1024–65535
59:-end of a
202:1025–5000
179:1024–5000
123:Windows 7
258:at node
225:See also
205:used by
153:OS and
149:used by
41:IP stack
183:FreeBSD
151:Solaris
115:FreeBSD
39:by the
27:) of a
496:
436:
256:procfs
125:, and
65:server
57:client
242:Notes
98:Range
91:Range
494:ISBN
439:6056
374:2021
367:6335
350:IETF
308:1350
291:IETF
157:OS.
25:port
434:RFC
364:RFC
354:doi
305:RFC
295:doi
155:AIX
19:An
586::
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348:.
342:.
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293:.
289:.
197:.
141:.
121:,
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316:.
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262:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.