anon.client

Class DummyTrafficControlChannel

java.lang.Object

anon.client.AbstractChannel

anon.client.AbstractControlChannel

anon.client.DummyTrafficControlChannel

All Implemented Interfaces:

java.lang.Runnable, java.util.Observer

public class DummyTrafficControlChannel
extends AbstractControlChannel
implements java.lang.Runnable, java.util.Observer

This channel sends dummy traffic full of random bytes, when no packets were sent by the multiplexer in a given interval. This makes it look as if the client is continuously sending traffic, strengthening the anonymity set of all users.

See Also:

anon.client.DummyTrafficControlChannel#DT_MAX_INTERVAL_MS}

Field Summary

Fields

Modifier and Type	Field and Description
static int	DT_DISABLE
static int	DT_MAX_INTERVAL_MS
static int	DT_MIN_INTERVAL_MS

Constructor Summary

Constructors

Constructor and Description
DummyTrafficControlChannel(Multiplexer a_multiplexer, IServiceContainer a_serviceContainer) Creates a new DummyTrafficControlChannel instance.

Method Summary

Modifier and Type	Method and Description
void	run() Lets the thread sleep for the given interval.
void	setDummyTrafficInterval(int a_interval) Changes the dummy traffic interval.
void	stop() Halts the internal dummy traffic thread.
void	update(java.util.Observable a_observer, java.lang.Object a_argument) This is the Observer implementation.

Methods inherited from class anon.client.AbstractControlChannel

isSending, processReceivedPacket, sendRawMessage

Methods inherited from class anon.client.AbstractChannel

createEmptyMixPacket, deleteChannel, isClosed, multiplexerClosed, sendPacket

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DT_MIN_INTERVAL_MS

public static final int DT_MIN_INTERVAL_MS

See Also:

Constant Field Values

DT_MAX_INTERVAL_MS

public static final int DT_MAX_INTERVAL_MS

See Also:

Constant Field Values

DT_DISABLE

public static final int DT_DISABLE

See Also:

Constant Field Values

Constructor Detail

DummyTrafficControlChannel

public DummyTrafficControlChannel(Multiplexer a_multiplexer,
                                  IServiceContainer a_serviceContainer)

Creates a new DummyTrafficControlChannel instance. The dummy traffic interval is set to -1 (dummy traffic disabled) and the internal thread isn't started. a_multiplexer The multiplexer the new DummyTrafficControlChannel instance belongs to.

Method Detail

run

public void run()

Lets the thread sleep for the given interval. If it was not interrupted by then, a dummy message has to be sent.

Specified by:

run in interface java.lang.Runnable

stop

public void stop()

Halts the internal dummy traffic thread. This method blocks until the internal thread has come to an end.

update

public void update(java.util.Observable a_observer,
                   java.lang.Object a_argument)

This is the Observer implementation. If a packet is sent or received on the connection, we get a notification from the multiplexer. When we get that notification the dummy traffic timer can be reset. The next dummy traffic packet is generated after the next timeout of the dummy traffic timer if we don't get another notification in the meantime.

Specified by:

update in interface java.util.Observer

Parameters:

a_observer - The observed object (Multiplexer).

a_argument - The notification (PacketProcessedEvent).

setDummyTrafficInterval

public void setDummyTrafficInterval(int a_interval)

Changes the dummy traffic interval.

Parameters:

a_interval - The new dummy traffic interval in milliseconds or DT_DISABLE, if dummy traffic shall be disabled.