IP Networking

What would be a realistic number of hosts in a 100BaseT network, before you have to start thinking on subnetting further?
Or in another words. How many hosts would you keep in the same broadcast domain?

In a 100BaseT network, with subnet 10.20.20.0/24, I could have 254 hosts as part of the same broadcast domain, would that be considered too many hosts "chatting" among them?

I would like to know what people that maintain networks would recommend.

That really depends on network traffic.

Posted from my Android phone.

Understandable! However I was under the impression that the hosts of a segment would be constantly broadcasting among them even if not much is actually "user generated traffic". Do I have the wrong impression?

Nevertheless, I wish to not miss the opportunity to ask you: by what rules could I come to the conclusion that the network is heavy on traffic?
Other than, "... hey, the network seems slow"

Would you mind to elaborate a bit?

Whether their traffic is all or even mostly broadcast depends entirely on what they're doing. If something's spewing broadcast video or disk images etc. to the network you'll obviously have a lot of broadcast. If you've got a hundred people running web browsers the traffic will be almost all non-broadcast. (Yes, there will be little bits of broadcast all the time, ARP requests and DHCP traffic and service announcements and all that, but these shouldn't amount to much.) Lacking my crystal ball, I really can't say whether you can put that many hosts on a subnet for what they're doing. The amount of available bandwidth versus the amount of used bandwidth, both between hosts and upstream/downstream.