4.4 Point-To-Point Protocol
Almost every Internet user will sooner or later come across PPP. It’s precisely the protocol that gives you trouble when you want to connect your PC to the Internet through a dial-up line or ADSL line. PPP most often uses frames similar to those of HDLC protocol. However, it doesn’t use all the possibilities that HDLC offers by far. But perhaps it introduces even more new features.
The basic features of PPP are as follows:
- On the physical level, it is able to use an interface in accordance with the recommendations V.24, V.35, and so on. It doesn’t require any control signals (RTS, CTS, DCD, DTR, etc.). However, control signals can be used to enhance its efficiency.
- It can use both asynchronous and synchronous (bit or character) data transmission.
- For asynchronous transmission, it uses 1 start bit, 8 data bits, and 1 stop bit (no parity).
- It requires fully duplex (two-way) point-to-point leased or dial-up lines.
- As a rule, it uses 16 or 32 bits...
