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Re: AFK Players in Whitegate and Besieged: Why aren't they autologged?
UDP packets are very basic. The have absolutly no overhead. It makes it were a lot more data can be sent out faster, the price for it though is that receiving end is not guarenteed to get the information.
Now you can compensate for this by creating software to check the data it receives and send back a request for missing info (or send the more important data multiple times). However if you are doing this for every bit of data coming over then you might as well just use a TCP connection (Since TCP is already built to this specification and is more Hardware driven then Software).
About the only major reason you'd want to do UDP with software checking the data is if only a part of the data is a must to receive and the other data (which happens to be the larger quantity) can essentially be ignored, or you want data accuracy but don't care about order in which it's received. As it is messages about the damage you've dealt and received can in most part be ignored as long as your HP bar and mob's HP bar is accurate.
The other downfall of UDP is data sent to you is not structured, it can easily be put out of order (This is another thing that TCP would prevent but the cost is a speed penalty), this is why you can see sometimes that someone responds about an item drop before it ever reaches you. In reality what happened is the item drop list and the guys responce got shuffled going from router to router when it finally got to you. One reason that could happen would be along the path your connection established to SE's servers it's likely a router was using a FILO (First in Last Out) structure instead of a FIFO (First in First out) structure.
Any easy way to think of it (for me anyway), is imagine someone with a deck of cards tossing them 1 at a time to another person, who also tosses them to another, and so on till it reaches the last person. In TCP any cards that fall to the ground person picks up and then also reorders the cards back from lowest to highest. In UDP any cards that fall to the ground are ignored and the guy just tosses what's in hand to the next person. Of course when the system does this it's more able to catch most of the cards.
So really when you see an anomily like that it means the first UDP packet your system received was the guys responce to the items and right after the items reach you, even though the server would of sent the items info first and then that player's comment second. This also were you get into those anomalies you see were players report someone being able to attack a target before them. It's also were you get the odd occurences of when you attack a mob at the same time someone else has and think you got claim to suddenly see it change on you.
UDP is fast but still needs something to mask the delay that's still there and that's were you have the system coding predictions on what the out-come is till it gets a confirmation from the server.
The one time I can recall the game actually lagging from server side I was still able to move, type, and think I was sending messages. The truth of the matter though is all the stuff I had sent when the server recovered from it's lag were ignored. I happened to be in the middle of a shot when this happened, and what's funny is when the server recovered it continued the actions I had started.
So I was running around poking other players, waving, doing LS messages, etc... and getting no responce they were all like statues once they finished the fight with whatever mob they were fighting. About the only moving other then me were the mobs, yet they didn't engage in fights or aggro. Then suddenly out of the blue my character finishes the shot animation I started back in a different area of the zone.
The funny part of it all was I didn't think anything of it till I suddenly saw a train of Yagudo (Far more then I could handle) coming at me. They were clearly from the area of the zone I was at when I started the shot.
Ehh, sorry for the story. Mind trailed there. Oh, got to say that's a decent illustration there Icemage. Not entirely accurate but it is simplified for better understanding on what's happening.
Originally posted by little ninja
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UDP packets are very basic. The have absolutly no overhead. It makes it were a lot more data can be sent out faster, the price for it though is that receiving end is not guarenteed to get the information.
Now you can compensate for this by creating software to check the data it receives and send back a request for missing info (or send the more important data multiple times). However if you are doing this for every bit of data coming over then you might as well just use a TCP connection (Since TCP is already built to this specification and is more Hardware driven then Software).
About the only major reason you'd want to do UDP with software checking the data is if only a part of the data is a must to receive and the other data (which happens to be the larger quantity) can essentially be ignored, or you want data accuracy but don't care about order in which it's received. As it is messages about the damage you've dealt and received can in most part be ignored as long as your HP bar and mob's HP bar is accurate.
The other downfall of UDP is data sent to you is not structured, it can easily be put out of order (This is another thing that TCP would prevent but the cost is a speed penalty), this is why you can see sometimes that someone responds about an item drop before it ever reaches you. In reality what happened is the item drop list and the guys responce got shuffled going from router to router when it finally got to you. One reason that could happen would be along the path your connection established to SE's servers it's likely a router was using a FILO (First in Last Out) structure instead of a FIFO (First in First out) structure.
Any easy way to think of it (for me anyway), is imagine someone with a deck of cards tossing them 1 at a time to another person, who also tosses them to another, and so on till it reaches the last person. In TCP any cards that fall to the ground person picks up and then also reorders the cards back from lowest to highest. In UDP any cards that fall to the ground are ignored and the guy just tosses what's in hand to the next person. Of course when the system does this it's more able to catch most of the cards.
So really when you see an anomily like that it means the first UDP packet your system received was the guys responce to the items and right after the items reach you, even though the server would of sent the items info first and then that player's comment second. This also were you get into those anomalies you see were players report someone being able to attack a target before them. It's also were you get the odd occurences of when you attack a mob at the same time someone else has and think you got claim to suddenly see it change on you.
UDP is fast but still needs something to mask the delay that's still there and that's were you have the system coding predictions on what the out-come is till it gets a confirmation from the server.
The one time I can recall the game actually lagging from server side I was still able to move, type, and think I was sending messages. The truth of the matter though is all the stuff I had sent when the server recovered from it's lag were ignored. I happened to be in the middle of a shot when this happened, and what's funny is when the server recovered it continued the actions I had started.
So I was running around poking other players, waving, doing LS messages, etc... and getting no responce they were all like statues once they finished the fight with whatever mob they were fighting. About the only moving other then me were the mobs, yet they didn't engage in fights or aggro. Then suddenly out of the blue my character finishes the shot animation I started back in a different area of the zone.
The funny part of it all was I didn't think anything of it till I suddenly saw a train of Yagudo (Far more then I could handle) coming at me. They were clearly from the area of the zone I was at when I started the shot.
Ehh, sorry for the story. Mind trailed there. Oh, got to say that's a decent illustration there Icemage. Not entirely accurate but it is simplified for better understanding on what's happening.
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