Difference Between SLIP and PPP

SLIP vs PPP

SLIP (Serial Line Internet Protocol) and PPP (Point-to-Point Protocol) are two protocols that are used in interconnecting two points in order to facilitate the transmission of data to and fro. Although they can be used with different types of media, the most typical use is with telephone lines for an Internet connection; used to establish digital communication between the user and the ISP. The main difference between SLIP and PPP is in their current use. SLIP is the older of the two and had a very minimal feature set. This eventually led to the creation of PPP and its more advanced features, thus rendering SLIP obsolete.

One of the key features in PPP is its ability to auto-configure its connection settings during initialization. The client and host communicate during initialization and negotiate on the best settings to be used. This is unlike SLIP which needs the settings coded beforehand in order to establish a successful connection. Auto-configuration significantly simplifies setup since most settings do not need to be entered manually.

Another essential feature added into PPP is error detection and recovery. In the process of transmitting data, it is very possible that a packet or two gets lost along the way. PPP is able to detect errors and automatically initiate the recovery of the lost packets. SLIP does not have any provisions for error detection so it needs to be implemented on a higher level. Not only does this add complexity, it also increases the processing needed.

Although SLIP is obsolete and is no longer used in most computer systems, it still enjoys some use in certain systems like microcontrollers. This is because of the relatively small amount of overhead that it adds. In order to transmit a packet, PPP adds a header as well as padding information in the end. In comparison, SLIP simply adds an end character at the end of each packet. In applications where the features of PPP are not really needed, using it is just a waste of bandwidth as the header and padding would always be there. In this case, using SLIP is actually more advantageous than PPP.

Summary:

1.SLIP is obsolete and has been replaced by PPP in most applications.
2.PPP can auto-configure settings while SLIP cannot.
3.PPP provides error detection and recovery while SLIP doesn’t.
4.SLIP has very minimal overhead compared to PPP.