Few questions in network design

[shivajikobardan]

Provide IT infrastructure details for a government school with 4 departments including ISP department which are around 500 meters apart from each other. Three departments have 5 labs each with around 24 computers in each room. ISP contains server farm with server like DNS, DHCP, E-mail, FTP and webserver and the main interet router which will be connected to the upstream provider. Propose appropriate equipment (L1,L2 and L3) and physical wires for the network design.

Solution-:



1)
D1=24*5=120
D2=120
D3=120
ISP 5 hosts

2) Components required-:

a) One main router and other routers for each department and ISP.
b) servers
c) Optical fibre to connect between 2 departments and ISPs.
d) CAT 6 cable to connect to internet in hosts.
e) Wireless access point to use wifi in laptop.
f) laptop/pcs
g) switch (why do we need switch when there is router in every step in this case? I don’t see a point of using the switch)


3) Subnetting network design, logical network design-:

Assume IP address be 192.168.0.0/23

4) Physical network design(non redundant)

I tried visio and other network diagramming softwares, I could not do justice there, so I redraw the network multiple times and made this ok diagram. Hope you understand it.

Questions-:

1) How will we make this network redundant? Will the below figure work(that solution?)

2) What are L1,L2 and L3 components in this? Probably it’s asking core, distribution and access layer. My guess

main router is core(I don’t think it’s as it is just the ISP),

Secondary routers and switches are distribution layer components

Hosts are access layer components.

This topic surprisingly has no similar questions answered anywhere else although the subnetting part of this is fairly common thing in many examinations. I would love to spend my whole life reading top down network design but unfortunately my course doesn’t allow me to do so.

A similar question answered here in this book-:

 

[networkingsignal]

Here I added the one more helpful question:

Why would a layer 2 switch need an IP Address?

Layer 2 switches need an IP address in order to be able to communicate with other devices on the network. Without an IP address, the switch would not be able to send or receive any data.

The main reason why a layer 2 switch needs an IP address is that it is responsible for routing traffic between different subnets. In order to do this, the switch needs to have a unique IP address so that it can be identified on the network.