Networks - hop to hop and end to end.

Hi, 

I have recently started working through basic IT support requirements, and basic networking. I want to change career basically - I won’t bore you with details. 

There is a very good guy on YouTube who explains these things v well, but one thing is tripping me up……..do you need hop to hop networking AND end to end? Don‘t they both just ’want’ to achieve the same thing. I understand each has different headers etc, so I figure you need both to move data from X to Y. OR are they seperate entities and can exist and function independently from one another? If you look at hop to hop, is it not just achieving an end to end function, by moving data through routers? If it were possible to JUST do end to end, from one machine straight to another - why bother with hop to hop, involving routers etc?

Can end to end function without routers (like those implemented with hop to hop)? I hope I’m explaining it ok?

Thank-you for reading, 

Matthew

I have never heard of hop to hop or end to end networking.  SO can you explain what you want to know?

Yeah, not sure what you mean, but my guess is just at which level you look at things regarding network protocols.  To have a connection from PC to PC or from PC to server (end to end), data packets need to move from hop to hop throughout the network, so this is a lower level work, invisible to the end-user.

Great that you wish to learn about Networking.

The thing that you are talking about is not really that basic. There are several basic networking principles that are not understood that lead to this confusion. Moreover that I do not know the source of your information nor do I know of its quality. I created this little diagram here.

 diagram1.png   32.01KB   0 downloads

Hop to Hop is concerned, as the name implies, with what is happening from one hop to the next, which I marked in RED.

End to End is concerned with what is happening from one end to the other end, here marked in BLUE.

A possible point of confusion here is the understanding of what is meant by a 'Hop', which is simply the immediate path from one device in a network to the next.
Dominique1 isn't all that wrong about it. It's mainly about the scope with which you look at data transmission.

The 'Why' and 'How' of this concept, as I have mentioned before, isn't all that basic. The significance of this will become clear to you automatically when you understand the fundamentals of networking.

For example look at the Open Systems Interconnection Model (OSI) and study it in conjunction with network devices (Switches, Routers, Hubs, Firewalls,...) and network protocols (ARP, DHCP, HTTP, STP, OSPF,...).
Look up what 'Encapsulation' is and how it works. Check out the 'Cisco Packettracer' for a Network Simulation program.

Thank- you very much for your replies. I was basically trying to work out if both are required, because end to end seems the more prefable, if it could be achieved - all you would need was an IP. BUT then I started to think, what if they do different requirements, so instead of both doing the same with different tactics of doing it (like 2 car engines running side by side - one would be fine - we don’t need 2 in a car), its more like they both are required - and do different functions - so to use the car metaphor again, one is the wheels, one the engine - BUT they are both required to complete the over all task. 

I just feel a bit stupid not being able to grasp the OSI model for those 2 aspects. 

This is the link to the set of videos I’m using to learn as fast as I can. 

https://www.youtube.com/watch?v=0aGqGKrRE0g&t=231s