Help on how to fix packet loss!

[wooohooo]

I have my desktop and laptop both set up in the room. With my desktop I'll run pingtest and get packet loss from 5-45%. While I run my laptop right next to me and get only around 0-2%. This 5-45% on my desktop makes it incredibly difficult to play online games. I've looked at how to do a line quality test but for some reason it still won't let me do one. Any one have any ideas? It was fine a few days ago but all of a sudden games lag so much.

[Rathji]

Without all the info, can't say for sure. I assume you are pinging the same server in your tests, and that it is located online and that your laptop is on wireless and desktop is wired in?

If so, the simple answer is something is probably wrong with at the physical level. Either NIC (PC or in the router) or network cable. Check to see if the cable is pinched, try swapping out another NIC in the PC, use a different port on the router, try a cable you know is good.

[wooohooo]

Originally Posted by Rathji

Without all the info, can't say for sure. I assume you are pinging the same server in your tests, and that it is located online and that your laptop is on wireless and desktop is wired in?

If so, the simple answer is something is probably wrong with at the physical level. Either NIC (PC or in the router) or network cable. Check to see if the cable is pinched, try swapping out another NIC in the PC, use a different port on the router, try a cable you know is good.

Both computers are running wireless. Router is in another room, but the computers when doing tests are on the same servers (I think) on pingtest.com

[HeartsOfFire]

Originally Posted by wooohooo

I have my desktop and laptop both set up in the room. With my desktop I'll run pingtest and get packet loss from 5-45%. While I run my laptop right next to me and get only around 0-2%. This 5-45% on my desktop makes it incredibly difficult to play online games. I've looked at how to do a line quality test but for some reason it still won't let me do one. Any one have any ideas? It was fine a few days ago but all of a sudden games lag so much.

Originally Posted by wooohooo

Both computers are running wireless. Router is in another room, but the computers when doing tests are on the same servers (I think) on pingtest.com

No serious gamer will run on any connection that isn't hard wired.

[Rathji]

Originally Posted by wooohooo

Both computers are running wireless. Router is in another room, but the computers when doing tests are on the same servers (I think) on pingtest.com

Then it might be the wireless card itself, or other electromagnetic interference that exists in a small localized area of the PC that is causing the problem. For example, if there are a bunch of cables (especially power cables) right beside the wireless adapter it could have an effect.

edit: re-reading your post you say the computers are beside each other, so interference from other sources is less likely.

[FanIn80]

nm

[wooohooo]

Originally Posted by HeartsOfFire

No serious gamer will run on any connection that isn't hard wired.

I'm not serious gamer at all. I'll occasionally play starcraft, but when I do it's a PITA. It's a little annoying not just with gaming but I notice it with other things like watching sports high lights pauses every 5 seconds, or even watching youtube videos.

And the fact it's almost impossible for me to be wired in. I would need to snake a 120 foot cable around my apartment.

[Rathji]

Originally Posted by wooohooo

I'm not serious gamer at all. I'll occasionally play starcraft, but when I do it's a PITA. It's a little annoying not just with gaming but I notice it with other things like watching sports high lights pauses every 5 seconds, or even watching youtube videos.

And the fact it's almost impossible for me to be wired in. I would need to snake a 120 foot cable around my apartment.

Try it.

Just move your computer if you need to. If you can nail down if it is your wireless or not, then you can look into ways to improve that performance.

[HeartsOfFire]

Originally Posted by wooohooo

I'm not serious gamer at all. I'll occasionally play starcraft, but when I do it's a PITA. <snip>.

[photon]

You could also try changing the channel of the wireless network, each channel uses a slightly different frequency.. 1 and 6 and 11 don't overlap with each other.

[wooohooo]

Originally Posted by photon

You could also try changing the channel of the wireless network, each channel uses a slightly different frequency.. 1 and 6 and 11 don't overlap with each other.

You are one very very smart man!!!

[photon]

that worked?

\o/

[wooohooo]

Originally Posted by photon

that worked?

\o/

Put it on channel 11 and everything works perfectly! Thanks man!

[theonlywhiteout]

can a person a bit more in the know explain to me how packet loss and jutter... work? like.. what makes it bad?

[Rathji]

I have no idea what jutter is. Jitter on the other hand is the variance that you have between packets arriving. It can be caused by packets taking different routes, or by a piece of equipment (router, switch etc) that is sending the packet out sending them at strange times for a variety of reasons. As I understand it, and I really don't because it isn't a level of networking I ever deal with, it is bad because packets usually need to be assembled in order as they come in, so if you have a delay then the processor needs to wait to put the next packet in. Also if jitter is really bad, over 50%, you can get packets coming in the wrong order, which can slow things down getting them put back together.

Packet loss is when a packet is sent but, due to some problems with the network, it doesn't arrive. This means the receiving device that is expecting the packet has to request it again after a certain delay (timeout), which means you could have a variety of thing happen but in general it makes things slower because there is more traffic being sent (duplicate packets) and the timeout and transmission delays caused by waiting for those packets.

[HeartsOfFire]

Originally Posted by Rathji

I have no idea what jutter is. Jitter on the other hand is the variance that you have between packets arriving. It can be caused by packets taking different routes, or by a piece of equipment (router, switch etc) that is sending the packet out sending them at strange times for a variety of reasons. As I understand it, and I really don't because it isn't a level of networking I ever deal with, it is bad because packets usually need to be assembled in order as they come in, so if you have a delay then the processor needs to wait to put the next packet in. Also if jitter is really bad, over 50%, you can get packets coming in the wrong order, which can slow things down getting them put back together.

To further elaborate on this...

The world of TCP/IP is different from most means of communication that we are used to. We are used to receiving information in chronological order from beginning to end. When we communicate with one another -- whether by spoken or written word -- we form our sentences in a manner that our peer can understand them. sentence senseless up in a inherently -- sentence while the become the same Mixing -- can cause words message to.

Downloading large files best describes how data transmission over TCP/IP works, particularly when using a bittorrent program. Most bittorrent programs I'm aware of allow you to see not just a progress bar, but also a pictograph depicting what data you have thus far. Every single time, you will notice that you have packets all over the place, rather than arriving in sequential, chronological order. It's like a jigsaw puzzle that your PC is slowly putting together as it receives all the pieces, except your computer uses the overhead data sent with each packet to determine where in the file each and every packet is expected to go. Jitter has little to no effect on this.

However, when the IP world is used for real-time communications -- i.e. live streaming video or voice communication -- suddenly there is a restriction put in place. Data must be sent and received in the same order between peers, otherwise the message will not be understood by the receiving peer. These scenario's are the most adversely affected by jitter, as there is no lee-way in the sending and receiving of packets. System B cannot ask system A to resend lost packets, because by the time it takes to request a retransmit, process the request, resend the packet, receive it and process it, is too long. It is already too late; the puck is in the net. Now you'll have to wait to see it on the slo-mo replay because you missed it live.

[sclitheroe]

Originally Posted by HeartsOfFire

However, when the IP world is used for real-time communications -- i.e. live streaming video or voice communication -- suddenly there is a restriction put in place. Data must be sent and received in the same order between peers, otherwise the message will not be understood by the receiving peer. These scenario's are the most adversely affected by jitter, as there is no lee-way in the sending and receiving of packets. System B cannot ask system A to resend lost packets, because by the time it takes to request a retransmit, process the request, resend the packet, receive it and process it, is too long. It is already too late; the puck is in the net. Now you'll have to wait to see it on the slo-mo replay because you missed it live.

Are you trying to explain the difference between UDP and TCP? The key point with UDP is that there are no guarantees on packet delivery, and hence there is no packet re-odering on the receiving host as there are no re-transmits. This is fine for real-time streaming apps since they have no use for the delays incurred with packet re-odering, as you've noted. They know how to deal with occasional dropped packets.

[HeartsOfFire]

Originally Posted by sclitheroe

Are you trying to explain the difference between UDP and TCP? The key point with UDP is that there are no guarantees on packet delivery, and hence there is no packet re-odering on the receiving host as there are no re-transmits. This is fine for real-time streaming apps since they have no use for the delays incurred with packet re-odering, as you've noted. They know how to deal with occasional dropped packets.

No, but you bring up a very good point. What I am describing is the effect of jitter on different communication methods.

Jitter on a TCP datastream is -- at worst -- a minor inconvenience.

On a UDP datastream, it's immediately service impacting.

[sclitheroe]

Originally Posted by HeartsOfFire

On a UDP datastream, it's immediately service impacting.

True, but you can do a small amount of buffering to compensate, otherwise VoIP would be basically unusable on most networks.

Some days it amazes me that any of this networking stuff works at all, even though I know better. For all its complexity, diversity, warts, and hacks at the low level, IP networking is pretty amazingly good.