I get "market data connect lost" message a couple of times during the trading day. My internet is generally reliable ATT fast fiber. Not sure what it causing it.
If it occurs daily rest 100% assured it is not IB. I run IB gateway daily and there are no disconnects, not in the past 2.5 months anyway. In case you talk about TWS there is a daily reset (time depends on the IB server you connect to) which lasts a short time but even during that time you can submit orders and get fills, it is only that the data feed in TWS may reset for a moment. That's at least been my own experience though I am using the gateway now for a while rather than TWS.