It’s good to understand theory and even though you can really only partially map TCP\IP onto the model, it helps with memorising and clarifying the different parts of a packet.
Unofficially, I think it also helps introduce the mindset of what happens to a lot of Working Groups and Standards by Committee. They can have all the best intentions in the world, but sometimes the hack works better and\or is more popular and you just have to get used to it. See Also: JavaScript, UPnP, X500 addressing scheme, dot1q, NAT.
It’s good to understand theory and even though you can really only partially map TCP\IP onto the model, it helps with memorising and clarifying the different parts of a packet.
Unofficially, I think it also helps introduce the mindset of what happens to a lot of Working Groups and Standards by Committee. They can have all the best intentions in the world, but sometimes the hack works better and\or is more popular and you just have to get used to it. See Also: JavaScript, UPnP, X500 addressing scheme, dot1q, NAT.