Alright! have you read the title? Im hoping that you won’t stop scrolling down because at the first place, a CCNA reviewee must be an I.T./ engineering guy who dealt already with this OSI and TCP/IP model and probably has learned a lot to their professors. So what’s the purpose of this blog, aside because I wanted to learn more, one thing that I struggled to compare these models is to make it easy for me to explain it in job interviews. Job interviews also let me explain the different layers and thier functions.So what I did is the keyword technique:
Application–>services to application processes
In simple, it provides network services to application processes, so come to think of a network service, we use network to transfer file, FTP and HTTP are there. So that is just my way to explain application layer.
Presentation-encryption,translation and compression
From the word itself, the goal of this layer is to ensure that the data is PRESENTABLE or READABLE by the system
SESSION- establish, manage and terminates
How I explain Session layer is how I use my facebook log-in,scroll down then log out, as simple as that.
TRANSPORT- responsible for the delivery of a message from one process to another.
With this layer, it ensures the whole message in tact and in order, we will deal further to this layer on the next blog
NETWORK- best path determination
The network layer is the layer that chooses what is the best path should a packet goes.
DATA LINK – error control and hardware accessing
The function of data link layer is to combine packets into bytes and bytes into frames. Each frame has a header and a trailer. Only the Data link has the trailer, it contains FCS for ERROR control
DATA LINK is divided into two;
LLC- Logical link control used for error detection and flow control
MAC- for hardware accessing
PHYSICAL–> delivery of bits from one device to another
Always think of physical layer as the physical connection or the medium used for communication.
I’m so sorry for beating around the bush, so let’s get into the topic- the purpose comparison or the pro’s and con’s of the TCP/IP and OSI
PURPOSE: standardization of the devices; OSI was created by ISO to standardize the devices. It means your Samsung headset will work with your lenovo laptop. OSI and TCP/IP were the competing models before up until TCP/IP has won against OSI because OSI development suffered because of slow formal standardization process.By the way, TCP/IP was created by the US Department of Defense and a lot of volunteers from different universities helped the development of TCP/IP