For 400 systems how many ports of switches need

[j.sivasankar92]

for an example

In our office only 400 systems are available. We cannot buy a Cisco switches because of more cost.
So we've to buy a net gear or sys link switches. So how many ports of switches need.

Really I can't to understand...

next kindly please how to connect from broadband connection

[icecream-guy]

you need 1 port for each connection,   so 400 + 1 for broadband

[deanwebb]

There also needs to be a switch port available for connecting to another switch. Two ports if you want to have high availability for your distribution switches - which I do recommend so that you don't have all your access switches cascading off of each other.

[j.sivasankar92]

Hmm! It's okay if I have 48 port Cisco switch. How many systems able to connect to the switch

[icecream-guy]

Hmm! It's okay if I have 48 port Cisco switch. How many systems able to connect to the switch

48

[deanwebb]

Well, that's 48 endpoints if you're not linking the switch to anything else.

And to the OP, you really do not want to have a chain of switches in serial. You will likely want to have access switches for your endpoints, and then those access switches would connect to a distribution switch that will handle communication between the switches.

[Fred]

For 400 devices, are you planning on zero redundancy?

You could do 400 devices with off the shelf switches.  Take a 24-port gigabit switch. Subtract one for your internet gateway, and you'd have 23 available ports for devices.  Connect each of these to another 24-port gigabit switch, and you'd have 23-ports on each of those available.  I'll let you do the math from there.

And I'd fire any engineer who thought that was a good design.