6 min readConcept sheetDefinition and protocol MCQs
Internet, intranet, e-mail and conferencing
The internet is a global network of networks using TCP/IP; an intranet is a private network inside one organisation, built on the same technology.
Internet began asARPANET, USA, 1969
WWW proposed byTim Berners-Lee at CERN, 1989
Send / receive mailSMTP / POP3 or IMAP
ExtranetIntranet opened to authorised outsiders
Internet, intranet and extranet
| Network | Who can use it | Example |
|---|---|---|
| Internet | Anyone | Public websites, e-mail, search |
| Intranet | Only members of the organisation | A college staff portal with internal circulars |
| Extranet | Members plus authorised outsiders | A portal shared with suppliers or partner institutions |
E-mail essentials
| Term | Meaning |
|---|---|
| To / Cc | Main and copied recipients, visible to everyone |
| Bcc | Blind carbon copy: recipients hidden from the others |
| SMTP | Protocol that sends mail |
| POP3 | Downloads mail to one device, usually removing it from the server |
| IMAP | Keeps mail on the server, in sync across devices |
| Attachment | A file sent along with the message |
| Spam | Unsolicited bulk mail |
| Phishing | Fraudulent mail that tries to steal passwords or money |
Synchronous and asynchronous communication
Synchronous (same time)Everyone takes part live: video conference, live webinar, chat, phone call.
Asynchronous (own time)People take part at different times: e-mail, discussion forum, recorded lecture, blog.
Audio and video conferencing
- Needs a camera, microphone, speakers and enough bandwidth (measured in bits per second).
- A codec (coder-decoder) compresses audio and video for sending and decompresses it on arrival.
- VoIP carries voice over internet networks instead of telephone lines.
- Latency (delay) matters: high latency makes live conversation awkward.
- A webinar is a web-based seminar: one or a few speakers, many listeners.
How NET asks this: tell internet, intranet and extranet apart, match e-mail protocols with their roles, or classify a tool as synchronous or asynchronous.
Typical MCQ: “Which e-mail field hides recipients from one another?” Bcc (blind carbon copy).
Typical MCQ: “Is a discussion forum synchronous or asynchronous?” Asynchronous: participants post and reply at different times.
SMTP sends, POP pulls down, IMAP stays in sync.