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67 lines
2.3 KiB
Plaintext
67 lines
2.3 KiB
Plaintext
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Routing Protocol.
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The routing protocol will only be used when two clients have difficulty
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connecting to each other. This is usually because of NAT issues. For example,
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two people who are behind symmetric NATs are not capable of connecting to each
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other directly.
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The routing protocol severely limits the speed at which two clients can
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communicate. This is so that the user of the software does not feel the need to
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turn it off because it is taking too much bandwidth and to prevent peers from
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using it without good reason.
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The routing protocol does not provide any anonymity, only convenience.
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#############
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Draft of protocol:
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Alice wants to connect to Bob.
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Alice queries the DHT and manages to obtain the ip_port of Bob from Carol and
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Dan both of who are closest mathematically to Bob in the DHT.
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Unfortunately Alice is enable to connect to the ip_port for Bob provided by
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Carol and Dan.
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Alice assumes then that Bob is behind a bad NAT.
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Alice therefore randomly picks between Carol and Dan. She picks Carol.
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Alice connects to Carol using the Lossless UDP protocol.
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She then sends a routing request over the connection:
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[char with a value of 16][Public key of who to route the packets to(client_id)
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(32 bytes)]
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Carol checks if she is connected via the DHT to the person (Bob) who the public
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key appears in the routing request.
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If she is not she kills the connection.
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If she is, she waits for the next data packet to arrive from Alice.
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As soon as she receives it she connects to the person (Bob) and sends it to him.
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If nothing is received from Bob within a timeout, the connection is killed.
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If something is received from Bob, it is sent to Alice and the connection is
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confirmed and continues until either Bob or Alice disconnect.
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#############
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Some notes:
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If both Alice and Bob are friends they will create two different connections
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when each try to connect to each other witch is good because it means data can
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be sent/received on both which lower the chances of the connection being
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severed because the node shut itself down or data being lost because of a bad
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node. It however doubles the amount of data we send/receive.
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If both peers manage to connect to each other, the routing connection is
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killed.
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All data transmitted trough this protocol must be encrypted in a way that it is
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only decryptable by the receiver and only the receiver.
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