Under Construction
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Under Construction

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Without fundamental simple definitions, all other tedious work is done in vain.
A Base is essential for clarity in developing possible pathways to application
constructions. Knowledge without practicality remains in the fantasies of man.
Sadly, our unity is divided where ignorant arguing leaves us empty attacking
both truth and deceptions. Can we unite in understanding?
~ Working to improve the lives of all ~

       Transmission Control Protocol        User Datagram Protocol
Well-known ports = 0 to 1,023
  Registered ports = 1,024 to 49,151
     Dynamic ports = 49,152 to 65,535
        (Private)

A connection between two computers uses a socket.
A socket is the combination of IP address plus port.


Stream Control Transmission Protocol (SCTP)
Datagram Congestion Control Protocol (DCCP)
                  
TCP UDP
Reliable Unreliable
Connection-oriented Connectionless
Segment retransmission
and flow control through
windowing (Slider acknowledgment)
No windowing or
retransmission
Segment sequencing No sequencing
  Acknowledge segments     No acknowledgement


All ports support TCP/UDP protocols. Sometimes Protocols use two ports, one for control configuration
and one for data transfer.   In some instances, control and transfer are conveyed on the same port.
Application specific as to TCP or UDP implementation, i.e. – (Port 7) Ping=UDP, Traceroute=TCP

PORTS
    
= Noteworthy  
    
= File Transfer  
    
= Encrypted/SSL  
    
= Email  
    
= Remote Access  
PORT SERVICE DESCRIPTION TCP UDP SCTP NOTES
7 ECHO Echo   TCP UDP   Server sends back an identical
copy of the data it received
20,21 FTP File Transport Protocol
 ⦁ 20 for data transfer
 ⦁ 21 for control commands
  TCP UDP SCTP Provides the ability to easily relocate
files from one system to another
22 SSH Secure Shell TCP UDP SCTP Uses a cryptographic (encrypted) protocols
operating securely over an unsecured
network in a client-server architecture
SFTP Secure File TCP SCTP
SCP Secure Copy TCP UDP SCTP
23 Telnet Telnet protocol - unencrypted
text communications
  TCP UDP   Connect to routers (TCP); designed to provide a bi-
directional connection with other devices (UDP)
25 SMTP Simple Mail Transport Protocol TCP     Mail relay - used for sending email
" Sending Mail To People "
37 Time Provides remote timing stat’s
of internal processing events
  TCP UDP   Security Concerns: Gives remote attacker
info on host’s internal processing load
43 WhoIs WHOIS directory service   TCP UDP   nicname
47 GRE Generic Routing Encapsulation   ? UDP   Cisco tunneling protocol encapsulating protocols
inside virtual point-to-point links over an IP network
49 TACACS Terminal Access Controller
Access-Control System
  TCP UDP   Login Host protocol (AAA)
TACACS+ Encrypts the full content of each packet TCP   TACACS+ and RADIUS have
generally replaced TACACS (AAA)
Proprietary - CISCO
53 DNS Domain Name System   TCP UDP   Dangerous poisoning - attacks
TCP for Zone Transfers - UDP for Queries
67 DHCP Dynamic Host Configuration Protocol
(BOOTPS) - server
~ issues lease times/reservations
  TCP UDP   Issues automatic IP services; Uses
DORA = Discover, Offer, Request, Acknowledge
~ If DHCP unavailable, Automatic Private IP
Addressing (APIPA) used - 169.254.x.y
68 DHCP (BOOTPC) - client   UDP  
69 TFTP Trivial File Transport Protocol     UDP   File transfer without the session establishment
80 HTTP Hypertext Transfer Protocol   TCP SCTP Main protocol that is used by web browsers
88 KERBEROS A three-headed dog who guarded
the gates of Hades. Represents a
client, a server, and a Key
  TCP UDP   Authenticating agent, time stamped.
Uses secret-key asymmetric cryptography to
authenticate client-server applications.
110 POP3 Post Office Protocol version 3
  - Used for recieving email
  TCP     Basic email retrieval; Make sure to set
"save on server," - not default setting,
- deletes off server once downloaded
WARNING: Does not sync email
119 NNTP Network News Transfer Protocol   TCP UDP   For the USENET discussion system
123 NTP Network Time Protocol   UDP   Synchronized down to the milisecond
with U.S. Naval Observatory clocks
137 NETBIOS Network Basic Input/Output System   UDP   Naming service. Allows applications on
different computers to communicate
within a local area network (LAN)
138 NETBIOS (NetBIOS) datagram service   UDP  
139 NETBIOS NetBIOS session service   TCP  
143 IMAP4 Internet message access protocol ver. 4   TCP   Recieving email - Multiple client use;
Syncs email and folders with your
computer, saves files on server
156 SQL Server sqlsrv   TCP UDP   SQL Service
161 SNMP
Simple Network Management Protocol
   SNMPv3 - 1st to encyrpt
  UDP   Monitors information to best change
device behavior; cable modems, routers,
switches, servers, workstations, printers,
etc., uptime, model #, insecure by default
162 SNMP Trap Simple Network Management
Protocol Trap
  TCP UDP   Collection of informantion
Triggers alerts when thresholds are met
194 IRC Internet Relay Chat   TCP   Designed for group communication
in discussion forums, called channels
201 Apple Talk AppleTalk Routing Maintenance   TCP UDP   X
389 LDAP Lightweight Directory Access Protocol   TCP UDP   Remote connections, accesses and maintains
distributed hierachical directory information
427 SLP Service Location Protocol   TCP UDP   Application = svrloc
443 HTTPS Hypertext Transfer Protocol Secure TCP   SCTP Uses SSL, Secure Sockets Layer encryption
SSL VPN Secure Sockets Layer
virtual private network
TCP SCTP Secure Socket Tunneling Protocol
(SSTP) - Uses SSL/TLS
445 SMB Service Message Block   TCP   Microsoft-DS Over TCP/IP - Printers
CIFS (Common Internet File System)
- Sent directly (NetBIOS-less)
464 KPASSWD Kerberos password and
key changing services
  TCP UDP   X
465 SMTPS Simple Mail Transfer Protocol Secured TCP UDP   SMTP over SSL - should no longer be used
500 IPSEC IP Security   TCP UDP   ISAKMP / IKEv2 - (Internet Key Exchange)
514 SYSLOG Standard for message logging   UDP   Capture all IDs logs
520 RIP Routing Information Protocol   UDP   Used to advertise routing information among
routers and communicate optimal paths
546 DHCPv6 DHCPv6 - client   TCP UDP   Dynamic Host Configuration Protocol
547 DHCPv6 DHCPv6 - server   TCP UDP  
548 AFP Apple Filing Protocol   TCP UDP   AFP over TCP
569 MSN ms-rome   TCP UDP   Microsoft Rome Game Port
587 SMTPS Message Submission   TCP UDP   Default Mail Message Submission Agent (MSA)
Uses TLS encryption
636 LDAPS Secure LDAP TCP UDP   LDAP over SSL
989,990 FTPS  ⦁ 989 = (data) over TLS/SSL
 ⦁ 990 = (control) over TLS/SSL
TCP UDP   over SSL or TLS
992 TELNETS Bi-directional communications, Secured TCP UDP   End-to-end communications after SSL/TLS
is set up; user's data sent bi-directionally
993 IMAPS Internet Message
Access Protocol Secured
TCP UDP   Encypted over SSL/TLS
995 POP3S Connect using POP3 securely TCP     Over Secure Sockets Layer (SSL) -TLS
1433 MS SQL Microsoft Structured Query Language   TCP   Standard for database manipulation
1434 MS SQL Microsoft Structured Query Language   UDP  
500?
1701
4500?
L2TP Layer 2 Tunneling Protocol   UDP   Requires public key/utilizes IPSec
May be blocked by NAT
1720 H.323 H.323 call setup TCP UDP   Voice over IP (VoIP) signaling,
one of the earliest used
1723 PPTP Point-to-Point Tunneling Protocol   TCP UDP   One of the oldest VPN protocals
- Does not use certificates
1812 RADIUS 1812 = Authentication
  Remote Authentication Dial-in User
  Service ~ Encrypts only the password
1813 = Accounting
  UDP   Old technology, AAA dial up for
Authentication Authorize Accounting
1813 RADIUS-ACCT   UDP  
2049 NFS Network File System   TCP UDP SCTP Used by UNIX clients for file access
2427 MGCP Media Gateway Control Protocol   TCP UDP   VoIP used for phone calls
2727 MGCP Media Gateway Control Protocol   TCP UDP   Callagent
3260 iSCSI Internet Small Computer
Systems Interface
    Used to connect to SANs storage
3389 RDP Remote Desktop Protocol   TCP   Remote Desktop
5004 RTP Real-Time Transport Protocol   UDP dccp VoIP and/or video apps
5005 RTP RTP control Protocol   TCP UDP dccp VoIP and/or video apps
5060 SIP Session Initiation Protocol   UDP SCTP VoIP and/or video apps
unencrypted signaling traffic (RTP)
5061 SIP Session Initiation Protocol   UDP SCTP VoIP and/or video apps
encrypted traffic (SRTP)
5900 VNC Virtual Network Computing   TCP ?   Client/server graphical desktop sharing system
that uses the Remote Frame Buffer protocol
(RFB) to remotely control another computer
9100 JETDIRECT Allows computer printers to
be directly attached to a LAN
  TCP UDP   Printer on
HP network printing service
33434 Traceroute Traceroute network tracking tool   TCP UDP
33435 Traceroute Mtrace-multicast traceroute   UDP
X X X   X X X X


Common Network Ports - Professor Messer       PowerCert Port Forwarding Video

Iana.org - Port Number Assignments       VPN Ports & Port Forwarding

Common Ports - MIT      Common Ports Flash Cards      Memorize Ports

SpeedGuide.net

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IPv4 Help Area

0.0.0.0 – 255.255.255.255 = 4.3 billion possible IPv4 addresses

MAC addresses are only valid within a subnet
IP addresses are used to communicate between subnets

Useful Images
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Subnetting ITFree - IPv4 Pubic & Private Addresses - Private vs Public IP Addresses

Sunny Simplest Subnetting Video - Special and private IPv4 addresses - Sunny's IPv4 Videos

Professor Messer IPv4 Adresses - Classful Subnetting - IPv4 Subnet Masks - 7 Second Subnetting

Subnet-able

  Class A = 1.0.0.0 – 126.255.255.255  
  Class B = 128.0.0.0 – 191.255.255.255  
  Class C = 192.0.0.0 – 223.255.255.255  
  Class D = 224.0.0.0 – 239.255.255.255  
  Class E = 240.0.0.0 – 254.255.255.255  
   Default subnet Mask   

          255.0.0.0
          255.255.0.0
          255.255.255.0





R
E
F
E
R
E
N
C
E

27 26 25 24 23 22 21 20
128 64 32 16 8 4 2 1
/8
/9 /10 /11 /12 /13 /14 /15 /16
/17 /18 /19 /20 /21 /22 /23 /24
/25 /25 /27 /28 /29 /30
128 192 224 240 248 252 254 255




  ← Interval – Block Size





  CIDR Notation





  ← IP Octet decimal value
                (subnet mask)
 
  20 = 1
  21 = 2
  22 = 4
  23 = 8
  24 = 16
  25 = 32
  26 = 64
  27 = 128
  28 = 256
  29 = 512
210 = 1,024
211 = 2,048
212 = 4,096
213 = 8,192
214 = 16,384
215 = 32,768
216 = 65,536

2a = # of Network subnets
   a = # of usable "on" bits (1s)
            Calculate # of usable hosts
2x - 2 = # of assignable hosts
           x = # of "off" bits (0s)

CIDR = Classless Inter-Domain Routing - also known as supernetting
Classful Addressing = Five address classes based on the leading four address bits

 Byte 1 
8 Bits
 Byte 2 
8 Bits
 Byte 3 
8 Bits
 Byte 4 
8 Bits
CIDR
Class A → 
Network Host Host Host
255
11111111
. 0
00000000
. 0
00000000
. 0
00000000
   /8  
Network Network Host Host
255
11111111
. 255
11111111
. 0
00000000
. 0
00000000
  /16  
Network Network Network Host
255
11111111
. 255
11111111
. 255
11111111
. 0
00000000
  /24  
Class B → 
Class C → 

*IP addresses that begin with 0 or 127 are reserved for other functions

Tricks to five classes of IPv4                                                                                    
Class Purpose 1ST Octet
Range
Start / End Address Number of
Networks
Hosts /
Network
CIDR
Class A → Very Large Networks 1–126 1.0.0.0 – 126.255.255.255 128 16,777,216   /8
Class B → Large Enterprise 128–191 128.0.0.0 – 191.255.255.255 16,384 65,536 /16
Class C → Small Business 192–223 192.0.0.0 – 223.255.255.255 2,097,152 256 /24
Class D → Multicast 224–239 224.0.0.0 – 239.255.255.255 IGRP Protocols N/A
Class E → Experimental 240–255 240.0.0.0 – 254.255.255.255 Reserved N/A



 A    B    C   D E  
┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┻━━━━━━━━━━━━━━━━━━━━━━━┻━━━━━━━━━━┻━━━━━━┻━━━━┛  
0 128 192 224 240    255
                                                             
Classless addressing - subnets by borrowing bits to increase/decrease amount of networks/hosts
⭢ VLSM (Variable Length Subnet Masks)



Private IP Address   – Non-routable on Internet  (RFC 1918)
Class Address Range Purpose
Class A 0.0.0.0 – 0.255.255.255 Reserved - Default route
10.0.0.0 – 10.255.255.255 Class A Private Subnets
127.0.0.0 – 127.255.255.255 Loopback testing Block
Class B 169.254.0.0 – 169.254.255.255 APIPA - when DHCP fails
172.16.0.0 – 172.31.255.255 Class B Private Subnets
Class C 192.168.0.0 – 192.168.255.255 Class C Private Subnets
  
IP Host
Addresses
Off
Bits
Subnet Mask CIDR Octet
1 0 255.255.255.255
11111111.11111111.11111111.11111111
/32 No
Network
2 1 255.255.255.254
11111111.11111111.11111111.11111110
/31 4
4 2 255.255.255.252
11111111.11111111.11111111.11111100
/30
8 3 255.255.255.248
11111111.11111111.11111111.11111000
/29
16 4 255.255.255.240
11111111.11111111.11111111.11110000
/28
32 5 255.255.255.224
11111111.11111111.11111111.11100000
/27
64 6 255.255.255.192
11111111.11111111.11111111.11000000
/26
128 7 255.255.255.128
11111111.11111111.11111111.10000000
/25
256 8 255.255.255.0
11111111.11111111.11111111.00000000
/24
512 9 255.255.254.0
11111111.11111111.11111110.00000000
/23 3
1,024 10 255.255.252.0
11111111.11111111.11111100.00000000
/22
2,048 11 255.255.248.0
11111111.11111111.11111000.00000000
/21
4,096 12 255.255.240.0
11111111.11111111.11110000.00000000
/20
8,192 13 255.255.224.0
11111111.11111111.11100000.00000000
/19
16,384 14 255.255.192.0
11111111.11111111.11000000.00000000
/18
32,768 15 255.255.128.0
11111111.11111111.10000000.00000000
/17
65,536 16 255.255.0.0
11111111.11111111.00000000.00000000
/16
131,072 17 255.254.0.0
11111111.11111110.00000000.00000000
/15 2
262,144 18 255.252.0.0
11111111.11111100.00000000.00000000
/14
524,288 19 255.248.0.0
11111111.11111000.00000000.00000000
/13
1,048,576 20 255.240.0.0
11111111.11110000.00000000.00000000
/12
2,097,152 21 255.224.0.0
11111111.11100000.00000000.00000000
/11
4,194,304 22 255.192.0.0
11111111.11000000.00000000.00000000
/10
8,388,608 23 255.128.0.0
11111111.10000000.00000000.00000000
/9
16,777,216 24 255.0.0.0
11111111.00000000.00000000.00000000
/8
33,554,432 25 254.0.0.0
11111110.00000000.00000000.00000000
/7 1
67,108,864 26 252.0.0.0
11111100.00000000.00000000.00000000
/6
134,217,728 27 248.0.0.0
11111000.00000000.00000000.00000000
/5
268,435,456 28 240.0.0.0
11110000.00000000.00000000.00000000
/4
536,870,912 29 224.0.0.0
11100000.00000000.00000000.00000000
/3
1,073,741,824 30 192.0.0.0
11000000.00000000.00000000.00000000
/2
2,147,483,648 31 128.0.0.0
10000000.00000000.00000000.00000000
/1
4,294,967,296 32 0.0.0.0
00000000.00000000.00000000.00000000
/0
Valid Subnet Mask Values:              




R
E
F
E
R
E
N
C
E

Subnet
Mask
Octet Bit
Position
Added
Networks
Hosts /
Network
128 10000000 2 126
192 11000000 4 62
224 11100000 8 30
240 11110000 16 14
248 11111000 32 6
252 11111100 64 2
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↖                     ↑                     ↗






IPv4
Address Space
(4,294,967,296
Addresses)


IPv6 Addresses
  (340,282,366,920,938,463,463,374,607,431,768,211,456  
Addresses)


↙                     ↓                     ↘
 

Professor Messer IPv4 Subnetting Speed Tables
Masks Networks Addresses
/1 /9 /17 /25 128 2 128
/2 /10 /18 /26 192 4 64
/3 /11 /19 /27 224 8 32
/4 /12 /20 /28 240 16 16
/5 /13 /21 /29 248 32 8
/6 /14 /22 /30 252 64 4
/7 /15 /23 /31 254 128 2
   /8       /16       /24       /32       255    256 1
↙                      Professor Messer - 7 Second Subnetting                     ↘
Address  
128 0 128
64 0 64 128 192
32 0 32 64 96 128 160 192 224
16 0 16 32 48 64 80 96 112 128 144 160 176 192 208 224 240
8 0 8 16 24 32 40 48 56 64 72 80 88 96 104 112 120 128 136 144 152 160 168 176 184 192 200 208 216 224 232 240 248
4 0 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 68 72 76 80 84 88 92 96 100 104 108 112 116 120 124 128 132 136 140 144 148 152 156 160 164 168 172 176 180 184 188 192 196 200 204 208 212 216 220 224 228 232 236 240 244 248


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PowerCert IPv4 vs IPv6     TechQuickie IPv4 vs IPv6     Address Types IPv6

Professor Messer - IPv4 and IPv6 Addressing     Assigning IPv6 Addresses

IPv6 Subnet Masks     Configuring IPv6     IPv6 Address Types

How DHCPv6 works?     IPv6 address classification


Useful IPv6 Images
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Decimal Hex Binary Conversion   
  IPv6 Anatomy   
  IPv6 Addresses   
  IPv6 Addresses   
  IPv6 EUI64   
  IPv6 Vulnerabilities   
   LARGER
 PICTURE
IPv6 Global   
  IPv6 Bits   
  IPv6 EUI64   
 


IPv6 addresses are 128 bits long (32 hex characters)
2001 : 0DB8 : 0100 : 1111 : 0000 : 0000 : 0000 : 0001

Global Route Prefix Subnet ID Interface Identifier
2001
←⎼→
16 bits

 : 
0DB8
←⎼→
16 bits

 : 
0100
←⎼→
16 bits

 : 
1111
←⎼→
16 bits

 : 
0000
←⎼→
16 bits

 : 
0000
←⎼→
16 bits

 : 
0000
←⎼→
16 bits

 : 
0001
←⎼→
16 bits




Network Portion Host Portion

 
 
0000
  :   0000   :   0000   :   0001
Extended Unique Identifier

       EUI-48 = MAC Address
       EUI-64 = Static IPv6 Host address

       EUI-48 = 8c:2d:aa:4b:98:a7   
                       ┣━━━━━━━━━━┫  ┣━━━━━━━━━━┫
                        (manufacturer)      LAN Identifier
                                    (OUI)            (serial number)


EUI-64 =

____
  :   __FF   :   FE__   :   ____

8c2d
  :   aaFF   :   FE4b   :   98a7
Seventh bit has to change in EUI-64  

8e2d
  :   aaFF   :   FE4b   :   98a7

FE80:0000:0000:0000:8e2d:aaFF:FE:4b:98a7



FE80::8e2d:aaFF:FE:4b:98a7
┗━━━━━━━━━━━━━━━━━┛
Link Local Address

or

Global Unicast Address
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━┓


2001:0DB8:0100:1111:8c2d:aaFF:FE4b:98a7

Flipping the 7th bit reference:
  0

     1  

2 3
                                                            
  4

     5  

6 7
                                                            
  8

     9  

A B
                                                            
  C

     D  

E F


IPv4/IPv6 Comparisons
Situation IPv4 IPv6
Date of Origin 1974 1998
Length in bits 32 128
Number of
Addresses
232 = 4,294,967,296 2128 = 340,282,366,920,938,
463,463,374,607,431,768,211,456
Address
Format
Dotted Decimal
192.168.100.1
Hexadecimal Notation
2001:0DB8::4:AB:123:4567:8901:AD
Dynamic
Addressing
DHCP SLAAC / DHCPv6
IPSec Optional Mandatory
Header Length Variable Fixed
Minimal
Packet Size
576 bytes 1280 bytes
IPv4/IPv6 Special Addresses
Address Type IPv4 IPv6
Default Route 0.0.0.0/0 ::/0
Unspecified 0.0.0.0/32 ::/128
Loopback 127.0.0.1/8 ::1/128
Multicast 224.0.0.0/8 FF00::/8
Link Local 169.254.0.0/16 FE80::/10
Global Unicast N/A 2000::/3
Unique Local 10.0.0.0/8
172.16.0.0/12
192.168.0.0/16
FC00::/7
Documentation 192.0.2.0/24
198.51.100.0/24
203.0.113.0/24
2001:DB8::/32


IPv6
  ADDRESSING  

┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━╋━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
┃                                                    ┃                                                    ┃
   Unicast   
                              
  Multicast  
                              
   Anycast   
  ┃                                                                                                             
┃                                     ┏━━━━━━━━┻━━━━━━━━━━┓                                   
┃                                     ┃                                  ┃                                   
   
   
   
   
   ┃                    
  Assigned  
FF00::/8
   
      Solicited Node      
FF02::1:FF00:0000/104
     FF02::2 = all local routers
              
┃                                                                                                              
┏━━━━━━━━━━━┻━━┳━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━┓        
                                                     ┃                                ┃                           ┃                                   
Global
  Unicast  
2000::/3
3FFF::/3
   
  Link-Local  
FE80::/10
FEBF::/10
   
  Loopback  
::1/128
   
  Unspecified  
::/128
   
  Unique  
Local
FC00::/7
FDFF::/7
   
  IPv4 Embedded  
& Compatible
::/80   ~   ::/96
80 bits | 16 | 32 bits
* Internet Explorer (IE) 11 required for mouseover pop-up text dialog boxes to format (display) correctly

Solicited Nodes Multicast Group in IPv6

IPv6 Protocol
Neighbor Discovery Protocol (NDP)
       Neighbor MAC Discovery = Replaces IPv4 ARP
       SLAAC = Stateless Address Autoconfiguration (≈ DHCP)
       DAD = Duplicate Address Detection
       RS = Router Solicitation ‒▶ FF02::2
       RA = Router Advertisement ◀‒ FE80::(MAC)
       NS= Neighbor Solicitation ‒▶ 2001:88::(request for MAC)
       NA= Neighbor Advertisment ◀‒ 2001:88::(returns MAC)

IPv6 - Neighbor Discovery Protocol     IPv6- Duplicate Address Detection (DAD)


To Our Heavenly Father be the Glory
Who holds all numbers



Under Construction
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Under Construction

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