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Author Topic: 30ms Filter Possibility?  (Read 168 times)

aclark20

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30ms Filter Possibility?
« on: January 10, 2008, 10:12:00 AM »

Would it be possible to use one of the routers that take custom firmware to respond to the ping instead of sending it out to the net? Not sure how the ping signal is differentiated from other data sent through the router, but if it can be picked up by the router, it should be theoretically possible to modify some router firmware to spoof a response of the pings, making all the ping times limited only by your LAN.

Has anyone thought of that possibility?
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aclark20

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30ms Filter Possibility?
« Reply #1 on: January 10, 2008, 10:35:00 AM »

Nevermind.. found my own answer... turns out its not really a ping

From MeanMF at TeamXLink:
It's never actually measuring "ping".. All system link traffic is encrypted. Whenever two Xboxes start talking to each other, they go through an authenticated Diffie-Hellman key exchange which creates a new encryption key for that connection. This is a back-and-forth communication between the two systems. The whole exchange has to complete in a certain amount of time, or else the Xbox determines that something is up and cancels the connection. Adding 30ms of delay to each packet is enough to put it over the top.
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foogrrr

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30ms Filter Possibility?
« Reply #2 on: September 08, 2008, 03:53:00 PM »

hmmm, that seems a bit wierd.

i dont think the actual key exchange is the problem with the time delay.  given that the key exchange is timestamped, but only for key generation, and not for actual time-keeping purposes, i believe that the packets being sent out have a shorter TTL (Time to live) on the packets than XBL ones.  

I wouldn't see why the actual key generation/exchange would keep track of time, seeing as how variable conditions might exist (other than network latency). one large example being the dvd read/write speed which is a variable condition of all.

I would look more into the TTL of the packets.

cheers,
foogrrr
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