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Phanataz
06-03-2002, 10:53 PM
I have two computers hooked up to a linksys hub. The uplink port on the hub is connected to the cable modem.

Recently, i've been having trouble when two people are on both computers and playing UT online the same server. The pings on both computers start jumping from 100 to 400. When just one player is playing UT online, all is well. This had been going on for a few months, but I have had two computers connected to an online UT server many times before with no problems.

I recently tested my upload speed. 133 kbps (although it varies from test to test). Perhaps thats not enough speed for both players to be playing UT off of one cable modem?

Another theory is that I often see the collision light flicker on the linksys hub when there is alot of traffic. I've tried different network cables, but the collision light just keeps flickering. My guess is that the hub just isn't intelligent enough to sort out all of the packets..?

So instead of buying a router..could one set up a third computer as a router? Not sure if this would improve or worsen the situation.

_F7_
06-03-2002, 11:28 PM
Have you tried setting static IPs instead of the default DHCP? DHCP is nice and convenient, but traffic will get routed much better with static IPs.

I have the same router Phan so if you need a walkthrough, I'm usually on ICQ: 9424632 or AIM: Darokin00 or email: daboosh@swbell.net or just PM :p

Kingster
06-04-2002, 01:08 AM
Let me make sure of a couple of things, Phan... You are tied through a hub (not a router), correct? You are being handed 2 IP addresses (one for each PC) via DHCP, right?

Let me explain a couple of things about IP and the usage thereof by games such as UT...

Speed testers test the capability of sending a large chunk of data... Useful for sendin files...

Games like UT use small chunks of data... and a LOT of them.

It is VERY easy to saturate your connection with these small chunks even if they aren't using anywhere near your total "upload" capacity... It is this that I am willing to bet is introducing lag into your connection...

I used to see this quite often when playing Age of Empires: Conquerors on the Zone all the time. 3 other guys and I used to play from the same location on a regular basis, and we had to block our pings to the other players when setting up our games, as we were overloading our network with the pings. There wasn't that much data, but there were 4 of us, and we were each pinging the other 290+ players in the "room" and reporting our ping times to each of them... once every 15 secs. Needless to say, our ping times looked like hell, but once we got into game (and the Zone suspended our connection), our pings looked just fine.

So... My point is this... You are not using your connection to its maximum upload capacity... You are maxing out the number of packets per second you are able to send. Unfortunately, I don't know that there is anything that you can do about it in UT. I'll poke around a bit and see...

And to be honest, I don't think the router is going to help, but answer your question, you can set up a PC to do routing... I'll dig up some info on it.

Skunkinabox
06-04-2002, 01:55 AM
Frog, Squirrel and I all play UT through the same connection. We have the linksys router and a switch. All is well usually. Sometimes during the day we all cant play but at night we are fine. I know it is possible as we are living proof.

Good Luck

BTW I am currently behind a firewall in a dorm on campus. Is there anyway I can play UT online. I had to set some proxy settings in IE to get internet access. Is there anything I need to do in UT as well. Do I need to get ports opened up. Is there anything around this. PM me if you know anything so the topic of this thread doesnt change, thanks

Skunkinabox
06-04-2002, 01:56 AM
Sorry Phan, should have started a new thread for that last little bit.

Phanataz
06-04-2002, 04:33 AM
Hey thanks everyone..

F7 & Kingster -
Yes, I am using a hub, not a router. We have purchased two IP addresses and they are set statically on both computers.

It's not that two players CANT play online at the same time, but every few minutes the ping sky rockets. So my gut feeling is that theres something going on with the hub...although i couldnt say for sure. Can anyone explain the collision light on the hub and what it means exactly?

If I set a 3rd computer as a router.. would I need one network card for the cable modem..and then a network card for each computer (in this case, 3 cards total)? Or can I use one card for the cable modem..and then just one more card and plug that one into the HUB...and have each computer plugged into the hub. Then again, would I be back in square one?

Skunk...may I ask why you are using a router AND a switch? I am curious. Also, what do you have your Connection set to in UT.. LAN or DSL/Cable Modem? Both of my computers are set to LAN.

And as far as your question goes, i'm guessing those ports for UT would have to be open at the firewall.

Inkswitch
06-04-2002, 06:04 AM
It's not the hub. It's your bandwith. You are not just sharing your bandwith with your other PC, you are sharing it with your neighborhood. What you are seeing is your bandwith being peaked. I used to be able to play two peeps off of one modem when I first got cable. Then, as the subscribers increased, I couldn't get enough bandwith to play with two PCs on one connection. It sucks, but it is still better than a modem.

HailtheGoat
06-04-2002, 06:51 AM
Wow maybe I can actually help someone.

Skunk, you need to open up TCP ports 7777 and 7778 to play UT.
Not sure if they'll allow it???

Phan,

Using a PC as a router is NOT a good idea, you will be back to square one because you'll have to use that same hub to connect all your machines, except for the extra NIC that connects to your cable modem. A router will seperate segments to stop collisions but not the way you will be setting it up. Youwill still ahve one segment for your 2 PC's and they will still collide.

What you need to do to maximize your efficiency and get rid of your collisions is get a switch, not a router. Collisions are exactly what they sound like 2 packets trying to access the wire at the same time, can't happen. Collisions are normal in an ethernet enviroment, especially with a hub because a hub does not seperate collision domains. A hub is dumb it just lets everything go and doesn't care if another machine is trying to access the wire.

A switch seperates collision domains (a collision domain is a group of machines on a subnet that collide with each other) so in essence it only allows 1 packet at a time go across the wire. Your 2 machines will be able to "talk" to the world they just can't do it at the same time. By that I mean you can use them at the same time it's just in milliseconds or nanoseconds for a delay, you won't notice it.

Collisions do cause latency (slowness) to happen because your machines now have to resend the packets that collided and got dropped off nowhere.

A switch will help your collisions but not necessarily your bandwidth, like Ink says you share it with your neighborhood so someone might be downloading a gig or pr0n and taking up all your speed.

I use the Linksys Etherfast Cable/DSL 4 port switch at home and it works out pretty well. Not a great switch but who has money to buy one from Foundry or Cisco?

I hope I helped you understand collisions a little better. I'm not sure of your networking knowledge so if I didn't make sense at all, PM me and I'll break it down even better for you.

_F7_
06-04-2002, 08:24 AM
Yep Goat got it. Just to expand on what he says a little more...

The bad thing about hubs is that they are not "smart". They have no internal software to help route traffic. They simply take data coming in and broadcast it to all ports looking for the IP the traffic is supposed to go to. When you think of all your ports and the extra unnecessary data that is being broadcast, you can quickly see why you are having the problems you are having.

Think about picking up the Linksys 4port Cable/DSL Router/Switch.

Here's a little FYI for ya:

What is a switch? http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci213079,00.html

What is a router? http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci212924,00.html

LoPing
06-04-2002, 11:29 AM
Originally posted by _F7_
Think about picking up the Linksys 4port Cable/DSL Router/Switch.

I've got one of these hooked up to my cable modem and have gotten three computers playing various multiplayer games (including UT) at the same time.

Don't know the theory, but I'm proof-of-concept.

Phanataz
06-04-2002, 01:00 PM
thanks everyone! i am more educated now

Just making sure, but F7's recommendation of the "Linksys 4port Cable/DSL Router/Switch"...are three different units, right?

Makes more sense to use a router or a switch. I'm still a little confused as to what the difference is in the two. They both seem to perform the same functions (according to what i've been reading). Are switches cheaper because they lack certain features (like a built-in firewall).?

Oh, and a router can't prevent collisions but a switch can?

Phanataz
06-04-2002, 01:27 PM
Originally posted by Inkswitch
It's not the hub. It's your bandwith.

when i use dslreports.com to test my bandwidth.. i get about 130kbps UP.. is that not enough then?

Idle Idol
06-04-2002, 01:33 PM
hehe, all these routers and switchs. i just plugged my computers into each other with a x-over cable =)

--Idle, lazy...AND cheap

_F7_
06-04-2002, 01:41 PM
http://www.linksys.com/Products/product.asp?grid=23&prid=20

That's the one I'm talking about. It's capable of hooking up to a DSL or Cable connection and acts as a router but also has a 4 port 10/100 switch built in. It also has NAT functionality (Network Address Translation) which means you could theortically connect 250+ PCs to this badboy (using hubs/switches) and it will route traffic appropriately.

Also, you could dump the extra price of that 2nd IP address you purchased and hook all your PCs up to the switch which would use just 1 of the IP addresses from your ISP.

Nimda
06-04-2002, 04:32 PM
I use the D-Link DI704. Same features as the Linksys, but may be a little cheaper (was about $20 difference when I got mine, but that was a while back). It also is a router, and has a built-in 4 port 10/100 Switch and NAT Firewall. Got 2 PC's connected to it constantly, and a 3rd wire dangling so I can plug in my laptop from work when I don't want to go in the office (Use Cisco VPN to authenticate to work WAN from my cable provider).

One note: If you use one of these routers/switches, make sure you have a 10/100 card in your PC and not just 10. It DOES make a difference - especially when both PC's are online.

HailtheGoat
06-04-2002, 06:09 PM
Originally posted by Phanataz

Oh, and a router can't prevent collisions but a switch can?

A router will seperate large networks into smaller segments. These smaller segments will now collide with each other instead of the large network. A router makes it from one big collision site down to multiple.

They way you would set it up would still leave your 2 PC's on the same segment and therefore they will still collide.

A switch is kinda like a toll booth on a major toll road. All cars can't go until they pay their dues, so since all cars can't go at once there will be no collisions.
It may seem as if this would slow down your network but it doesn't we are talking nanoseconds again. It speeds it up because your PC's are not trying to send out the same packets.

Kingster
06-08-2002, 08:32 AM
You can do one of two things, Phan...

1) Go get a switch and just replace your hub with it.

2) Go get a router/switch, call your ISP, drop an IP address, and let the NAT do the work. UT does work with NAT, but not having seen the UT2K3 network stuff yet, who knows how that will go...

Anyway... Either of these should fix your problem...

SoBeiT
06-09-2002, 10:41 AM
I ended up getting the same system F7 recomends. I found the wiring to the other room cost more than the unit did though. I also found I have to turn off ZA to play UT without going into the thousands ( ping wise ). Still have that darn lag/whatever that ruins the game sometimes. Good product Linksys.

Phanataz
06-09-2002, 03:59 PM
Roger that.. the ping problem seems to happen at random. can't afford a router right now, but will certainly look into it.

I will also try the ZA idea.

Phanataz
07-02-2002, 06:40 AM
i've been investigating the problem with multiple computers and high pings.

What I found was that when I join a server (with both of my computers) that has NO UTPure installed, the pings are just fine. I've tried this theory with about 3 random non-UTPure servers. The pings were excellent on all three.

As soon as I get both of my computers connected to a server with UTPure, the pings go through the roof. This is on servers that are just a few miles from my house!

I've tried deleting all instances of UTPure, clearing cache and .tmp files, and updating my network card driver. Still nothing works. I highly suspect UTPure.. at least, the newest version.

Oh, and if I play with just one computer connected, the pings are fine.. with or without UTPure.

Very strange. I didnt used to have this problem.

Anyone else have this problem lately with multiple computers connecting to a UTPure server?

btw: the ping problem doesnt improve with turning off the firewall and have nothing else running in the background.

HortonsWho
07-02-2002, 06:54 AM
Phan-

You should report that in the Midnight Interactive forums. (http://www.midnightinteractive.com/forums/index.php3?s=) They might find that helpful or already have a thread about it.


:)

SnapsProvolone
07-19-2002, 10:41 PM
I do know that hubs cause packet loss. I use switches only.