How dialup works?
A dial-up service connects to the Internet through your phone line (Known as PSTN). The modem in your PC "calls" an Internet Service Provider (ISP) and connects with a maximum speed of 56,000 (56k) bytes per second speed connection. Each time your PC dials into the ISP, it is assigned an Internet Protocol (IP) address. A different, unique IP address is assigned at the beginning of each visit so that the ISP can recognize your PC and make sure you can send and receive email, surf the Internet, and so on; basically, this address lets your ISP know where to send the information you are requesting through your modem. In terms of hackers, in order for someone to gain access to your computer, it would be necessary for them to know your IP to successfully do so. The fact that your IP address constantly changes essentially makes your dial-up Internet connection more secure.
Dial-up technologies are traditional dial-up connection over PSTN, Dial-up through Wi-Fi and Internet Roaming (ex: iPass).
Advantages of a Dialup Connection
1. Low Price. To implement a Dial-up system in an ISP and also for end user it takes considerably low price. Most ISPs provide their service 2/- per 5 Minute rate.
2. Secure Connection. Because, your IP address continually changes hackers or some other malware will unable to use it. Also, this connection is not always on connection. But, it is not 100% away from hackers.
3. Offered in rural areas. If you have a phone, and its service provider is able to provide the Internet, you want only a modem to get on with it. No special base stations requirements.
4. Dial-up works very smoothly with Text Only Web Browser.
5. Some ISPs provide special speedup implementation operations on data requested by a dialup connection. As an example, Netscape ISP uses a compression program that squeezes images, text, and other objects at the server, just prior to sending them across the phone line. This is known as Server Side Compression. Some modems use ‘on-the-fly compression mechanisms’ as a speedup operation.
6. ISPs do not have to implement special infrastructure other than the telephone network. Therefore dialup is widely available. No need for base stations.
7. Easy to setup. User just has to connect the modem and input information given by ISP.
Disadvantages of Dialup
1. Slow Speed. Maximum speed a dial-up connection can achieve for online viewing is 56k/s. This is very incompatible with modern high-tech web pages.
2. A Phone line is required. Dialup connections cannot be taken as a satellite or wireless/HSPA modes. Also, your telephone supplier must also be an ISP. Wi-Fi Dial-up systems are very rare.
3. Busy signals from other users. When sharing same telephone line, connection losses occurs frequently and also long busy signals occurs.
4. ISPs add limits on connection durations and automatically disconnect user from system to prevent hogging of access
5. When server side compression executes, it will reduce the quality of pictures. User may have greater difficulties when he downloads larger images such as wallpapers.
6. Many new ISPs provide infrastructure only for Broadband connections and Dial-up are out of proper maintenance.
7. Dial-up requires time to establish a usable telephone connection. This also includes handshaking time and both these will add to the bill too if it is time-metered!
8. Dial-up never works with media streaming. For example, online radio stations never work there.
9. Dial-up connections usually have latency as high as 400ms or even more, which can make online gaming and video conferencing difficult. However some games such as Star Wars: Galaxies will run under 56k dialup modem.
10. Modem should be connected via PCI slots or RS232 cable. Very few dial-up modems can be plug-in to USB.
11. Dial-up require the full use of a telephone line. When you use phone line to the Internet access, any call receives during that time may not be connected. This can be overcome by using a modem that can identify calls or by using other specialized devices. But at about every occasion, it uses full line.
12. In a dial-up connection, modems are used to translate digital into analogue signals and communicating with Internet. Analogue transmission between the subscriber and the telephone company is a bandwidth bottleneck. Dialup connection speeds make it more difficult to view certain types of media, such as video, and it can take much longer to download and open email attachments, play online games and so on.