BIG Problem in our LAN

Question

Hi every one,
In our company we have the topology below:
It seems that the LAN is stable , and everything works fine, for saving  user’s data we use mechanic ways : we  visit every user and we save its data with external hard drive, so we want to use some software that can help us making saving users’ data easy for us, like symentec backup exec or other automatic ways,
Before doing it, I save one document (size = 9 Go)   using the LAN, this document is in the server_1
And will go Through the switch_1 and switch_2 to my laptop,
During this operation, we can’t make phone call with phones connected to switch_3 , And sometimes we  some users cannot work in server_2
All switches are 48 ports
So I think that the problem is with the switch_1: its bandwidth is not enough
I can’t take any decision because I’m not sure I have many suggestions:
•1)      backbone switch
•2)      Separate data from the voice
•3)      Adding another switch
•4)      Linking the Avaya to switch_2 and servers to switch_3
•5)      Buy  Cisco switches  and replace  the Enterasys Swithes
Hope it was clear and I hope I will get the good answer, thank you.

Answer 1

I would if possible, put you servers in a different VLAN from your user and voice data if the Enterasys Switches could do. This will seperate the traffic flows and will only aid you in finding the solution. Configure the Enterasys device to do the routing between the devices if possible as you would with the core, this will stop the fortigate or router from being congested.
Ensure your servers are running at speed 1000 and duplex full as well as your fiber connections. if not possible ensure your gigabit connections configured properly.
If the switches are unmanaged switches i would look at option 5, if that is not feasible I would strongly recommend a re-architecture put all the data intensive users near your servers.