Thread: How Dial-up internet works ?

This article is posted for IBF competition, hope you will find it useful.

In-spite of progress and penetration of broadband, many people still use traditional Dial-up connection. Process is fairly simple, you dial-in to ISP with help of modem and telephone line and start browsing. Simple ? But a lot goes in background.

To explain overall technical process in layman's language think yourself touring France or Germany where you don't even understand what they speak. How will you communicate now ? Best option is you will hire a translator which will convey your message to other person and vice-versa. Same goes in Dial-Up communication. You need a telephone line, Modem and ISP. Modem here is the translator as mentioned in above example.

1. When a user dials a connection , the networking protocol built into OS directs modem to dial ISP phone number.

2. This digital communication is converted to analog signal by modem which then travels along the telephone wire and reaches to a node at ISP.

3. At ISP's node, there is another modem which accepts this incoming analog signal and converts it into digital data which ISP host computer can understand.

4. When a connection is dialed,your current OS Networking protocol sends your user name and password to the ISP using a process called CHAP. i.e, challenge handshake authentication protocol.

5. At ISP, this info is checked against a DB maintained by host.

6. When above conversation takes place, your telephone hogs the line for that particular duration. Hence no-one can call you on phone when you are online.

7. Once you are authenticated, you are Online and can surf the internet.

Recommended Reading :How Torrents Works ?

very informative article..

last year, as an aftermath of depression, 40% of homely bb users of USA switched back to erstwhile dial up connection..


i myself have fetish for dial up thingy, the way you can use a landline for internet still stinks outta me..

Originally Posted by mickey

very informative article..

last year, as an aftermath of depression, 40% of homely bb users of USA switched back to erstwhile dial up connection..


i myself have fetish for dial up thingy, the way you can use a landline for internet still stinks outta me..

Thanks. Glad that you liked it

Nice article Anil

Originally Posted by meetdilip

Nice article Anil

Thanks Dilip

Good one..........