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GreenBean-HH-
10-06-2009, 10:28 PM
Here's the real question: How does a player who's ping is over 100 able to point their weapon directly at a player who's running and get a hit? There must be a way to calculate the effects of ping in order to accurately measure what the expectations are when looking at someone's ping.


ping is a computer network tool used to test whether a particular host is reachable across an IP network; it is also used to self test the network interface card of the computer, or as a latency test. It works by sending ICMP “echo request” packets to the target host and listening for ICMP “echo response” replies. Ping measures the round-trip time[1] and records any packet loss, and prints when finished a statistical summary of the echo response packets received, the minimum, mean, max and in some versions the standard deviation of the round trip time.


RFC 1122 prescribes that any host must accept an echo-request and issue an echo-reply in return.

Thus I assume that while playing a game a ping is issued and the time for the gamer to receive a return 'echo-reply' is measured as the ping number we see in-game.

I have to assume that everyone on a particular server is issuing pings at the same rate, or sending out another request after it receives an 'echo-reply'.

If I'm wrong on any assumptions I make, please let me know.


In gaming

Main article: ping (video gaming)
In various network multiplayer games, the server notes the time it requires for a game packet to reach a client and a response to be received. This round-trip time is usually reported as the player's 'ping'. It is used as an effective measurement of the player's latency, with lower ping times being desirable. Note that this style of ping typically does not use ICMP packets.


Latency in a packet-switched network is measured either one-way (the time from the source sending a packet to the destination receiving it), or round-trip (the one-way latency from source to destination plus the one-way latency from the destination back to the source). Round-trip latency is more often quoted, because it can be measured from a single point. Note that round trip latency excludes the amount of time that a destination system spends processing the packet. Many software platforms provide a service called ping that can be used to measure round-trip latency. Ping performs no packet processing; it merely sends a response back when it receives a packet (i.e. performs a no-op), thus it is a relatively accurate way of measuring latency.

One question I have is how does someone with a low ping preceive a player with a higher ping... what is their behavior. I can imagine the high ping player, say over 300 will have a hard time navigating as there is such a large delay between the request to move their player forward and seeing the result on their own screen. For a low ping player I imagine we see them move forward straight into walls and wonder what they're doing crashing into walls all the time.


In computing and especially computer networks, lag is a term used where the computer freezes and then continues some time later when an action is performed, for example clicking a mouse button. If there is different latency, such as distance between computers connecting, the term used is delay although many get it mixed up with lag.


While strictly every packet experiences lag, the term lag is used to refer to delays noticeable to the user. There is often a correlation between latency and the physical distance that data must travel. Thus the time taken for a packet to travel from a computer server in Europe to a client in the same region is likely to be shorter than the time to travel from Europe to the Americas or Asia. But protocols and well written code that avoid unnecessary data transmissions are less affected by the latency inherent in a network. Modern corporate networks have devices to cache frequently requested data and accelerate protocols, thus reducing application response time, the cumulative effect of latency.

In many online video games, internet lag is undesirable because it disrupts normal game-play. Due to this, many players that have a high latency internet connection are often not permitted, or discouraged from playing with other players or servers that have a distant server host or have high latency to one another. Very often it also causes the death of the player when its character engages in combat. Extreme cases of lag may result in extensive desynchronization of the game state. The game may attempt to correct this by pausing game-play and attempting to fully resynchronize all players. Games that do not or fail in the attempt may simply drop the offending players. A reverse is shown when the player is near to the server geographically, allowing for, in some cases, almost instant transfer of data, and therefore no lag.


What I'd like to know is how much time = 10 ping? (as a reference) to start to understand what effects players with higher pings are dealing with when playing. Put another way, what is the actual time difference between a player that has a ping of 10 and a player that has a ping of 100?



In simulation applications, 'latency' refers to the time delay, normally measured in milliseconds (1/1,000 sec), between initial input and an output clearly discernible to the simulator trainee or simulator subject. Latency is sometimes also called transport del


Internet gaming
Network gaming requires very low latency, but requires limited throughput, often as low as a few kilobits per second. The required maximum latency is game type dependent. In first person shooters under 100 ms is required (sometimes even lower)[citation needed]. In strategy games the maximum latency could be allowed to reach 600 ms, depending on the game.[citation needed]


Did i miss it? What does a 100 ping amount to in real time? Does it equal 100 milliseconds?

I do believe i've confirmed it... if someone has a 100 ping, that means they have a delay of 100 ms or 100 milliseconds. Therefore the difference between a player with a 30 ping and one with a ping of 120 is, the higher player's connection is 4 times slower than the lower ping player.

If 1000 milliseconds = 1 second in real time... then 100 ping is a delay of 1/10th a second.



_________________________________________________

In more modern multiplayer online video games implementations, the server keeps track of where the user's avatar is, so having a high latency will always be the user's peril.

So if this is true, then other players will have the advantage against someone with a higher ping, if I'm understand this author correctly.

GreenBean-HH-
10-06-2009, 10:43 PM
Using the LagoMeter: Source: http://en.wikipedia.org/wiki/Lagometer

Game Console Key Command To Turn On Command To Turn Off
Call of Duty Tilde (~) /cg_lagometer 1 /cg_lagometer 0
Call of Duty: United Offensive Tilde (~) /cg_lagometer 1 /cg_lagometer 0
Call of Duty 2 Tilde (~) seta cg_drawLagometer "1" seta cg_drawLagometer "0"
Call of Duty 4: Modern Warfare Tilde (~) seta cg_drawLagometer "1" seta cg_drawLagometer "0"
Call of Duty: World at War Tilde (~) seta cg_drawLagometer "1" seta cg_drawLagometer "0"
Quake 3 Arena Tilde (~) /cg_lagometer 1 /cg_lagometer 0
Wolfenstein: Enemy Territory Tilde (~) /cg_lagometer 1 /cg_lagometer 0
Medal of Honor: Spearhead Tilde (~) cg_lagometer 1 cg_lagometer 0
Return To Castle Wolfenstein Tilde (~) /cg_lagometer 1 /cg_lagometer 0


http://upload.wikimedia.org/wikipedia/en/thumb/d/d9/Lagometer_normal.png/180px-Lagometer_normal.png
Quake III lagometer during normal play.


http://upload.wikimedia.org/wikipedia/en/thumb/3/34/Lagometer_spike.png/180px-Lagometer_spike.png
Quake III lagometer showing lag spike.

A Lagometer is a display of network latency on an internet connection and of rendering by the client. Lagometers are commonly found in computer games or IRC where timing plays a large role. Quake and derived games commonly have them. The delay between a request and its arrival is proportional to the height of the bottom column. The top column (horizontal line) shows the time the computer needs to render each frame. If it is below the line and blue, the computer has more time to render then it needs. If it is above the line and yellow, it did not have enough time to render and therefore had to skip frames. Also, this is used by some people to test lagging.
Some games that use a "Lagometer" will simply remove a player from the game if their lag is too high.
Use the following console commands for the following games:

I would like to know more about what the lagometer is telling us.


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Should bandwidth be part of this discussion? http://en.wikipedia.org/wiki/Bandwidth_(computing)

Moreno
10-07-2009, 12:00 AM
Did i miss it? What does a 100 ping amount to in real time? Does it equal 100 milliseconds?

From what I understand:

PING is measured in Milliseconds (MS). 1000ms = 1 second. So if you have 10ms, your connection is 1/100 of a second, or if your 100ms your connection is 1/10 of a second. The difference is enormous.


I would like to know more about what the Lagometer is telling us.

From what I know, the Lagometer is split into two sections. Top and Bottom. The top half displays information regarding world updates. Blue bars means that the world updates are being received & no frames are being dropped. Yellow bars mean the world updates are not being received & the frames are being dropped. So for the top, you want more blue than yellow. If your getting yellow. I would think about switching game servers.

The Bottom half displays information for the data packets getting received. The Green bars mean data packets are being received. Red bars mean that your losing data packets. The Yellow means corrupt data packets are being received but all together, it is the same as the red bars. Again, I would think about changing game servers if you are getting more red or yellow than green.

GreenBean-HH-
10-07-2009, 01:13 AM
Thanks Moreno, for both the ping and lagometer explanation.

I was actually updating the original post regarding that 1 ping = 1 millisecond when you posted (took a long break from my edit).


Based on " 1000 milliseconds = 1 second in real time... then 100 ping is a delay of 1/10th a second." what I'd like to see next is a video of someone running for one second representing 1000 ping, to see the distance that player would cover, or put another way, where a 1000 ping player would have to aim in order to hit a running player that had a say 25 ping.

Remember this:

Quote from: http://en.wikipedia.org/wiki/Ping_(video_gaming)
In more modern multiplayer online video games implementations, the server keeps track of where the user's avatar is, so having a high latency will always be the user's peril.
So it's not the low ping player that should have trouble aiming at any target, because the server will keep track of where all user avatar's are, but it's the high ping player who will have trouble compensating for all other players. So even if the 200 ping player shoots at another 200 ping player, there isn't a 400 ping delay between the players since the server is tracking both avatars... each 200 ping player would see their own individual 200 ping (1/5 second) delay.

At a low ping of say under 50 milliseconds, I believe I read that this is about where our normal brain can acknowledge movement anyway, so I think there is no advantage to pings lower than this... but I forgot where I saw this on Wiki so the amount may be wrong.

Aiming at Target diagram and animation:
With the first 1000 ping diagram, we could then easily make one for 500, 300, 200, 150, 125, 100, 75 and 50, especially in relationship to hit boxes of a player. That should give everyone a real idea of what to expect from players with higher pings and if they are really able to shoot directly at a target and still get a kill.

Like most of us, you've probably seen a higher ping player shoot directly at a moving target and consistently hit a wall behind the target... and you probably know more experienced players can compensate for this, that is, if you know you have a high ping then you should shoot further in front of a moving target to get an actual hit.

_________________________________________________
You should remind yourself just how long a second is by counting 1 thousand 1, 1 thousand 2, etc.

1000 ping = 1 second
500 ping = 1/2 second
250 ping = 1/4 second
125 ping = 1/8 second
67.5 ping = 1/16 second
50 ping = 1/20 second
25 ping = 1/40 second

I would suggest playing on a 250 ping server, if they'll let you in, so you can experience the lag for yourself, and one at 125 ping. I think the 250 will be very hard to even navigate through doors or through windows let alone trying to hit a moving target.
The 125 ping will also have it's challenges although navigation should be reasonable. Using the travel diagram we will make, I suspect with a 125 ping delay you'll travel about 3 or 4 feet (or 1 meter) which will allow you time to compensate, to align yourself to jump through a window, without looking too noobish. I suspect a 250 ping you'll travel between 6 and 8 feet or 2 meters, which will make you look awkward to anyone spec'ng you. We will see once the diagrams are completed.

Moreno
10-07-2009, 01:22 AM
Back in 2003 and 2004, I used to play internet games on a High Speed Satellite Connection. The only online game I could play was Delta Force Black Hawk Down. I had a ping ranging from 800ms-2000ms. I tested my shots and the distance I had to shoot ahead of the player to actually hit him. It was about 5cm-8cm because satellite is not a constant or steady ping. Since the game was made for dial-up players. The network on the developer is outdated. So even with Comcast I get 125ms with a server in Seattle. I live about 45 minutes away from the server. It is about a half of a centimeter I have to lead the player.

GreenBean-HH-
10-07-2009, 01:46 AM
Yeah, I read on Wiki about satellite connection users and the problems of that type of connection.

referring to 5cm to 8cm, i'd have to know your screen resolution, and also the distance you were to the target to figure out exactly the type of angle you had to shoot at... but to be honest I know exactly what you're saying as I did the same thing when I played MOHAA. In the diagram I'm planning, it will be very easy to see exactly how far in front of a player, using the 'hit box' as a measuring rod (so to speak)... so one could say "at 125 ping I have to aim one extra avatar body width to hit the target in the center..."

The first thing will be a video of someone running for one second (1000 ping). We will then mark the start and finish line and draw up a diagram showing the distance along with a scale figure of the soldier (various games have different speeds, but we'll start with COD4). Then it should be easy to break it down to other ping examples.

After all of that, we should discuss other factors that can improve someone's connection, or hurt their connections.


_________________________________________________

Just as a reference to what you said:

In older games:

In some cases, games seem to give unfair advantage to high-ping users, as in some implementations of the Half-Life network protocol and game engine. In these games, the player aided by the higher ping skips around, making it hard to judge where the character is exactly, and thus more elusive to target. For this reason, many servers automatically remove players with higher than average ping - with thresholds going as low as 130 milliseconds.

But, in more current games:

In more modern multiplayer online video games implementations, the server keeps track of where the user's avatar is, so having a high latency will always be the user's peril.

Moreno
10-07-2009, 03:34 AM
Yeah, older games deffinently gave an unfair advantage but it wasn't the best ideal for gaming ever. ??? On my screen, i played normal as I am now. But to others They would shoot me and I would die then 5 seconds or so later they would die.

GreenBean-HH-
10-07-2009, 02:36 PM
http://www.youtube.com/watch?v=b526M7mo9Wo

for footage of someone running for 1 second... at beginning .

will edit later and repost clipped version of this.

Moreno
10-07-2009, 11:32 PM
I am having a hard time spotting it, is their another example?

GreenBean-HH-
10-08-2009, 12:39 AM
at 0:11 it starts where i guy runs across and is being shot at.

i just grabbed this off youtube after looking at many vids... i will edit it and repost. then make a few diagrams from that. sorry, short of time this morning so this isn't the greatest example of what i was looking for. if you run across any better footage of someone running perpendicular to the shooter in the multiplayer game, then post the youtube url. thanks.