Problem with internet in Network

Hai
i am from chennai. I am having a problem with my network. I
am using sr224 linksys switch with airtel 110bx1 modem for 10 pc
network. The problem is the net keeps reconnecting whenever i switch a
few comps or more than 5 comps.

The connection setting is as follows

Airtel 110bx1 --> SR224 --> 11 Pcs

All the pcs use static ip.

My question is does this setup need a router or will the 110bx1 will do? If so suggest me a good router.

Why i am getting disconnecting problems after i switch on a few pcs

Thankyou.