BLANKOM IRD-6100 HD IRD User Manual
BLANKOM_IRD-6100_User_Manual_RR-V1.1-03-2018.doc
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called
dynamic and/or private ports
.
[2]
Both system and user ports are used by transport
protocols (TCP, UDP, DCCP, SCTP) to indicate an application or service.
Ports 0–1023
– system or
well-known ports
Ports 1024–49151
– user or registered ports
Ports >49151
– dynamic / private ports
https://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers
Range for Ephemeral port
The
Internet Assigned Numbers Authority
(IANA) suggests the range 49152 to 65535
(2
15
+2
14
to 2
16
−1) for dynamic or private ports.
[1]
Many
Linux kernels
use the port range 32768 to 61000.
[note 2]
FreeBSD
has used the IANA
port range since release 4.6. Previous versions, including the
Berkeley Software
Distribution
(BSD), use ports 1024 to 5000 as ephemeral ports.
[2][3]
Microsoft Windows
operating systems through XP use the range 1025–5000 as ephemeral
ports by default.
[4]
Windows Vista
,
Windows 7
, and
Server 2008
use the IANA range by
default.
[5]
Windows Server 2003
uses the range 1025–5000 by default, until Microsoft
security update MS08-037 from 2008 is installed, after which it uses the IANA range by
default.
[6]
Windows Server 2008 with Exchange Server 2007 installed has a default port
range of 1025–60000.
[7]
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
.
[8][9]
Packet structure
UDP Header
Offsets
Octet
0
1
2
3
Octet
Bit
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
0
0
Source port
Destination port
4
32
Length
Checksum
The UDP header consists of 4 fields, each of which is 2 bytes (16 bits).
[1]
The use of the
fields "Checksum" and "Source port" is optional in IPv4 (pink background in table). In IPv6
only the source port is optional (see below).
Source port number
This field identifies the sender's port when meaningful and should be assumed to
be the port to reply to if needed. If not used, then it should be zero. If the source
host is the client, the port number is likely to be an ephemeral port number. If the
