All of these are general ports used for email except which one?

All of these are general ports used for email except which one?

• 25
• 22
• 587
• 110           

EXPLANATION

Common port numbers

Main article: List of TCP and UDP port numbers

The Internet Assigned Numbers Authority (IANA) is responsible for the global coordination of the DNS Root, IP addressing, and other Internet protocol resources. This includes the registration of commonly used port numbers for well-known Internet services.

The port numbers are divided into three ranges: the well-known ports, the registered ports, and the dynamic or private ports.

The well-known ports (also known as system ports) are those from 0 through 1023. The requirements for new assignments in this range are stricter than for other registrations, examples include:

• 20: File Transfer Protocol (FTP) Data Transfer
• 21: File Transfer Protocol (FTP) Command Control
• 22: Secure Shell (SSH) Secure Login
• 23: Telnet remote login service, unencrypted text messages
• 25: Simple Mail Transfer Protocol (SMTP) E-mail routing
• 53: Domain Name System (DNS) service
• 80: Hypertext Transfer Protocol (HTTP) used in the World Wide Web
• 110: Post Office Protocol (POP3)
• 119: Network News Transfer Protocol (NNTP)
• 123: Network Time Protocol (NTP)
• 143: Internet Message Access Protocol (IMAP) Management of digital mail
• 161: Simple Network Management Protocol (SNMP)
• 194: Internet Relay Chat (IRC)
• 443: HTTP Secure (HTTPS) HTTP over TLS/SSL

The registered ports are those from 1024 through 49151. IANA maintains the official list of well-known and registered ranges. The dynamic or private ports are those from 49152 through 65535. One common use for this range is for ephemeral ports. 

SOURCE

https://en.wikipedia.org/wiki/Port_(computer_networking)

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what protocol should be used to send a password securely

what protocol should be used to send a password securely

• ftp
• smtp
• telnet
• ssh   

    

 EXPLANATION

File Transfer Protocol

The File Transfer Protocol is a standard network protocol used for the transfer of computer files between a client and server on a computer network. FTP is on Port 21.

Secure Shell

Secure Shell is a cryptographic network protocol for operating network services securely over an unsecured network. The best known example application is for remote login to computer systems by users.Secure Shell (SSH) uses TCP port 22.

telnet 

Telnet is a protocol used on the Internet or local area network to provide a bidirectional interactive text-oriented communication facility using a virtual terminal connection. Wikipedia

simple mail transfer protocol

The Simple Mail Transfer Protocol is a communication protocol for electronic mail transmission. As an Internet standard, SMTP was first defined in 1982 by RFC 821, and updated in 2008 by RFC 5321 to Extended SMTP additions, which is the protocol variety in widespread use today. Wikipedia

Standard port: 25, 587, 465

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Which of the following file replication methods is now used as a standard feature since Windows Vista and Windows Server 2008?

Which of the following file replication methods is now used as a standard feature since Windows Vista and Windows Server 2008?

• fcopy
• xcopy
• Robocopy
• Dfs 

EXPLANATION

Distributed File System (DFS) is a set of client and server services that allow an organization using Microsoft Windows servers to organize many distributed SMB file shares into a distributed file system.
DFS has two components to its service: Location transparency (via the namespace component) and Redundancy (via the file replication component). Together, these components improve data availability in the case of failure or heavy load by allowing shares in multiple different locations to be logically grouped under one folder, the "DFS root".
Microsoft's DFS is referred to interchangeably as 'DFS' and 'Dfs' by Microsoft and is unrelated to the DCE Distributed File System, which held the 'DFS' trademark^[1] but was discontinued in 2005.

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In a Windows environment, which command should you use in order to show the last time your machine was rebooted?

n a Windows environment, which command should you use in order to show the last time your machine was rebooted?

• systeminfo | find "System Boot Time"
• net stats workstation
• uptime
• systeminfo | find "System Uptime" 

EXPLANATION

systeminfo command is almost right what you need. On English Windows 7 you can also do:

systeminfo | find /i "Boot Time"

Or with the help of WMIC:

wmic os get lastbootuptime

The main difference between Windows 7 and Windows XP that in Windows 7 Microsoft can show only last boot up time. 

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What is the maxiumum distance for a CAT5E Cable?

What is the maxiumum distance for a CAT5E Cable?

• 11 Meters
• Infinite
• 100 Meters
• 30 Meters 

EXPLANATION

1000BASE-T (also known as IEEE 802.3ab) is a standard for gigabit Ethernet over copper wiring.

Each 1000BASE-T network segment can be a maximum length of 100 meters (328 feet), and must use Category 5 cable or better (including Cat 5e and Cat 6).

 The standards for Cat 5e and Cat 6 call for a maximum run length of 90 meters or 295 feet. While you may make a longer run and get it to work, this is not recommended. Even if problems don't show up immediately, they may come up later as your computers are upgraded to transmit faster or your network is expanded. If you must make a longer run, you can either put a signal repeater in the middle of the line or you can make your long run with fiber optic cable.
If your run is between 295 and 590 feet, the repeater option may be the best option for you. A switch or hub will act as a repeater. Make sure that you locate it in such a way that both runs on either side of the repeater are within the 90 meter standard. It won't do much good to split a 500 foot run into two runs of 100 and 400 feet.

If your run is longer than 590 feet or if most of the run is outside, fiber optic may be your best option. You'll need a media converter or fiber fed switch at each end of the fiber run to convert your network signals back and forth between electrical signals on copper and light pulses on fiber. If you are running fiber optic cable underground, you'll need to protect the delicate glass fibers inside the jacket by running it through a conduit or by using armored fiber optic cable.

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