Interview Questions

Difference between OSI and TCPIP Layers

WLAN testing FAQ


(Continued from previous question...)

Difference between OSI and TCPIP Layers

The networking industry has a standard 7 layer model for network protocol architecture called OSI model. The OSI model is standardized by ISO for networking community so that interoperability between different systems will become easy and all will have open access to the protocols.
As mentioned OSI model is divided into 7 layers while TCPIP model is divided into 4 layers. OSI stands for Open Systems Interconnection and TCPIP stands for Transmission Control Protocol/Internet Protocol.
OSI model divides application layer of TCPIP into 3 layers viz. application,presentation and session layers. OSI splits the network interface layer of TCPIP into 2 layers viz.datalink layer and physical layer. Layer-3(Network) and Layer-4(Transport) remains common in both OSI and TCPIP models. OSI and TCPIP
As mentioned in TCPIP model, network access layer corresponds to OSI model's physical and data link layers.
Physical layer converts data frames to be transmitted into stream of bits suitable to be sent over the medium. At the receiving end, physical layer converts back bits(electrical pulses) into data frames.
OSI's data link layer is divided into two sublayers viz. MAC and LLC.
MAC or Medium Access Control interfaces with the network adapter. LLC or Logical Link Control does error checking functions for the frames on the subnet and manages links

Other Interview Questions