It's a good point. Some cases can be attributed to server issues.

If its Battlefield1 like he mentioned, then it's fully capable of handling 64 players without lag or performance issues. We tested this on several of our heavier scenarios and all was fine. We did retire a couple of scenarios as they caused persistent and periodic stutter for most players but that was a map object issu (NW Germany has too many objects).

More recently I discovered that 6 C-47s dropping 16 paratroopers each will kill the server and lag everyone out. Did that just once :) But that would show on the user side as net lag, rather than a performance related freeze or stutter.

Nope. LAN setting in IL-2 means biggest packets, nothing else...

And when a packet gets lost (happens a lot), it needs to be re-send and re-checked.

Use 56k as already suggested. That will use the smallest packets. Use a wired connection. WiFi has a HUGE overhead bogging down your system even further.
You do need a far better computer with more RAM too. Your current computer probably has 100 Mb/s maximum Ethernet speed, to say nothing about the performance of the rest of the system. Ancient, maybe good for notepad, a bit of surfing (not even all sites will work), and the occational email.

When you say it runs IL-2 smooth, you probably mean on the absolute minimum settings?

1. Whether his current PC can provide 100 Mbit/s, 1 Gbit/s or just 10 Mbit/s doesn't matter at all. Any of these will do for IL-2.
2. I've been running IL-2 on a PC with less than half the CPU power (Pentium 4 w/ 3.0 GHz) and far sub-par GPU (4670 AGP) with perfect settings @XGA resolution with a solid frame rate of 30-40 FPS.
3. Explain why "not even all sites will work" on that PC and in contrast, which PC you've seen where all sites would.

I agree that it's not a top-notch PC which has been discussed in this topic, but that's no reason for the issues described.

Best regards - Mike

The Celeron 900 is a one core CPU, which runs at 2.2 GHz, it does not have twice the compute capacity of a Pentium 4 at 3.0 GHz.

It also depends which version of IL*2 under which operating system version. 1946 will run under Windows 7, I don't know what the most modern OS version that the original IL*2 will run under would have been, I originally ran it under Windows 98, but I'm pretty sure it won't run from the original disk under Windows 7.

IL-2 1946 runs on my Atom 330 ION under Windows 7 Ultimate 32 bit, but nowhere nearsmooth. Flying a single plane on an empty small map without objects like trees or even worse buildings will get me just about 20 - 30 fps.

I think the 2 GB is the biggest problem here. I am running 4GB DDR2-800 dual channel in my atom. The ION is much more capable than the Intel integrated graphics too, and the Atom is a dual core with hyperthreading (4 threads).

The amazing bit there is that the TDP is 8W... very low power CPU.