What is the purpose of limiting TCP and UDP from router?

From my limited understanding of TCP and UDP, they are just protocols for delivering a receiving packets, correct? Would there be any performance benefits to limiting the number of TCP and UDP connections? For instance, every time somebody else hops online, my gaming connection times out, despite having enough bandwidth to manage both. The bandwidth throttling controls are working correctly, but it still happens every time. I know I need to replace my modem, but am looking to at least make my home network a little more stable.

So the way that TCP and UDP were explained to me back in the day were that TCP was like having a back-and-forth structured conversation, where the speaker and listener acknowledge communications back and forth, while UDP is more of a one-way conversation where the speaker yells out as much information that the listener is capable of receiving.

In some cases, different web services utilize TCP versus UDP. In a lot of streaming content scenarios (such as streaming video, etc), UDP is utilized due to the more rigorous needs for continuous high bandwidth data transfer and other characteristics of the protocol versus TCP.

For your question, are you talking about limiting the number of active connections or are you talking about imposing limits on the amount of TCP/UDP bandwidth that a certain client can utilize?

What is your question precisely? Is it random disconnects or modem advice?

Limiting the number of active connections for UDP and TCP will alleviate an over utilization of the routers routing capacities (meaning translating URLs to IPs and resolving routes).
A modern browser is able to open a multitude of connections at the same time, sometimes for speed reasons sometimes out of sheer necessity due to the need to connect to multiple servers in case of scripting heavy pages. If too many packets hit your Router from your private network (meaning internal network) your router might take too long to respond and the server times out the connection i.e. terminates it. But I think you knew that already?

Getting a new router might be advisable in any case due to the fact that there might be no new firmware updates for your old plastic box and you are exposing yourself unnecessarily.

I'm running Tomato on it, not the default firmware. I'm sorry if I'm confusing you. I'm new to networking stuff, so all this terminology confuses me a bit. I just wanted to know if decreasing the number of TCP and UDP connections each device can access would help prevent connection timeouts. What would be the consequence of limiting those connections? Would webpages and services cease to load after you've hit your limit?

Number of connections. Under TCP Limt, it has an option to limit the maximum number of connections, while it has connections per second under UDP.

Well I'm an expert on UDP and TCP since right after lunch (I kid you not it was exactly the topic of todays lecture (concepts and methods of systems software)).

All packets have a time to live. This is so they do not clog up the network (which network, basically ANY/EVERY network) and just die if they do not arrive at their target in time. TTL (time to live, written in seconds) for webtraffic packets might be higher than for gaming packets and if there is a point in the connection that is too tardy packets might get dropped.

What kind of diagnostic tools does tomato have? Maybe they yield some interesting information. Other than that you could try and record ping times to various servers (maybe even a few gameservers) in different states of network load (Mainly TCP load (file transfers, try loading a bunch of linux iso files), UDP load (stream the heck out of your internet connection) and mixed loads. If your packets drop due to overaging (and if my theory of the short lived game packets is true) we might see an increased ping response time. You should as well test the different load states with a game and see whether the connection holds.

In which games does this happen?

Not many. I'm using a mini build due to not having a lot of NVRAM. There's a bandwidth monitoring tool, ping, trace route, connection logging and that's about it.

The only multiplayer games I have been playing are BF3 and BF4. BF3 just times out, while BF4 rubber bands a lot.

What model of router are you using?
Is the system your gaming on connecting to the router over wifi or by a cat5 cable?
What is your current bandwidth (down and up) for your internet connection?

WRT54GL. It's old, but stable with great range. I got it for dirt cheap. My PC is connected via ethernet, and my bandwidth is 3 Mbps down and 768kbps up. Fastest I can get in my area :(. The thing is that my connection goes wonky regardless of if somebody else is using 2Mb or 500Kb. I'm almost certain that my modem is the culprit, as I've experienced the same issue with other routers.

Sorry for replying back so late.

The WRT54GL may be old put it should be able to handle double that throughput while in NAT/Firewall mode; I have mine running in a bridge mode using ddwrt and I am able to pull 16.8mbit/6.7mbit using to bridge back to my ISPs all in one modem / router from my basement to my main floor of the house, in a very saturated 2.4ghz spectrum, on a good day I can only see a couple dozen SSIDs, on a bad day I counted 40 from my basement :(. Plus I run a mediatomb streaming server off of it back to my TV upstairs over the wireless link without any issues.

I'm assuming with those speeds you are on DSL through your Telco? I would look to your modem if that is the case, especially if it is an older model.