What is the default port number of HTTPS?
- A.21
- B.80
- C.110
- D.443
Correct answer
Explanation
The correct answer is D, 443. HTTPS is HTTP wrapped in encryption, and web servers listen for it on port 443. When an address begins with https, the browser opens a secure channel on that port, and the padlock shown beside the address means the traffic on it is coded.
Option A, 21, belongs to FTP, the File Transfer Protocol, which uses port 21 for commands and port 20 for the data itself. Option B, 80, is the default port of plain HTTP, the unencrypted form, and is the most tempting distractor because the two protocols do the same work. Option C, 110, is the port of POP3, which downloads incoming mail from a server. Keeping the set 80 for HTTP, 443 for HTTPS, 21 for FTP and 110 for POP3 in mind answers most port questions in one stroke.
Read the full article: Internet and Email: Protocols, Ports and Terms
Practice Questions
View allDeleted emails are stored in
- A.Drafts
- B.Trash
- C.Inbox
- D.Sent mail
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When a letter is deleted from a mailbox it is not wiped out at once. It is moved to a folder called Trash, or Bin in some services, and kept there for a fixed number of days so that a letter deleted by mistake can be restored.
Read the full explanation →In Gmail, the email address of the recipients can be entered in __________ field.
- A.Subject
- B.To
- C.Message
- D.From
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The To field of a mail window is meant for the addresses of the people the letter is written to.
Read the full explanation →ARPANET, the forerunner of the internet, carried its first message in which year?
- A.1959
- B.1969
- C.1979
- D.1989
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ARPANET was funded by the Advanced Research Projects Agency of the United States Department of Defense, and in 1969 it linked computers at four American universities and passed its first message between them.
Read the full explanation →Who is credited with inventing the World Wide Web?
- A.Vinton Cerf
- B.Charles Babbage
- C.Tim Berners-Lee
- D.Ray Tomlinson
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Working at CERN in Switzerland, he proposed a system of linked documents in 1989, wrote the first browser and server, and put the first website online in 1991.
Read the full explanation →Which symbol was chosen by Ray Tomlinson to separate the user name from the host name in an email address?
- A.#
- B.&
- C.@
- D.*
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Ray Tomlinson sent the first message between two computers on ARPANET in 1971 and needed a character that would never appear in a person's name.
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