uk.org.arlott.simon.hw.f24.lbsta
Class Bridge

java.lang.Object
  uk.org.arlott.simon.hw.f24.lbsta.Bridge

public class Bridge
extends java.lang.Object

Represents a bridge on the network.

Nested Class Summary

class

Bridge.HostCacheEntry Host Cache Entry object.

Field Summary

private static boolean[]	allIDs All the bridge IDs in use.
private int	forwardDelay Forward Delay set by root bridge in seconds.
private int	helloTime Hello Time set by root bridge in seconds.
private int	helloTimer Current Hello Time timer in milliseconds.
private static int	holdTime The Hold Time.
private java.util.HashMap<java.lang.Integer,Bridge.HostCacheEntry>	hostCache The host cache.
private int	id Bridge's ID.
private boolean	inNetwork Whether or not this bridge is in the network.
private static int	lastAssigned The last assigned bridge ID.
private Log	log The event log.
static int	MAX_ID The maximum bridge ID.
static int	MAX_PORTS The number of bridge ports to create.
private int	maxAge Max Age set by root bridge in seconds.
private static int	MESSAGE_AGE_INCREMENT The message age increment per hop.
private int	myForwardDelay Bridge's set Forward Delay in seconds.
private int	myHelloTime Bridge's set Hello Time in seconds.
private int	myMaxAge Bridge's set Max Age in seconds.
private Network	network The network this bridge is on.
BridgePort[]	ports The bridge ports on this bridge
private java.util.Vector<Packet>	queuedPackets Packets queued to be added to the network.
private int	rootID Current root bridge's ID.
private int	rootPathCost Path cost to root.
private BridgePort	rootPort Root port.
static int	TIME_INCREMENT The time increment per loop iteration.
private boolean	topologyChange The Topology Change flag.
private boolean	topologyChangeDetected The Topology Change Detected flag.
private int	topologyChangeNotificationTimer The Toplogy Change Notification timer.
private int	topologyChangeTimer The Topology Change timer.
int	x The X co-ordinate position of this bridge.
int	y The X co-ordinate position of this bridge.

Constructor Summary

Bridge(int x, int y, Network network)
Creates a new Bridge.

Method Summary

private void	acknowledgeTopologyChange(BridgePort port)
void	addToNetwork() Adds this bridge to the network.
private void	becomeDesignatedPort(BridgePort bp)
private void	configBPDUGeneration()
private void	configurationUpdate()
private boolean	designatedForSomePort()
private boolean	designatedPort(BridgePort port)
private void	designatedPortSelection()
void	disablePort(BridgePort port)
void	enablePort(BridgePort port)
private static int	findFreeID() Finds an unused bridge ID.
private void	forwardDelayTimerExpiry(BridgePort port)
int	getForwardDelay() Gets the bridge Forward Delay.
int	getHelloTime() Gets the bridge Hello Time.
java.util.HashMap<java.lang.Integer,Bridge.HostCacheEntry>	getHostCache() Gets the host cache.
int	getID() Gets the ID.
java.lang.String[]	getLog() Gets the log entries for this bridge.
int	getMaxAge() Gets the bridge Max Age.
int	getNetworkForwardDelay() Gets the network Forward Delay.
int	getNetworkHelloTime() Gets the network Hello Time.
int	getNetworkMaxAge() Gets the network Max Age.
int	getRootID() Gets the root ID.
private void	helloTimerExpiry()
private void	holdTimerExpiry(BridgePort port)
void	initialise()
private void	initialisePort(BridgePort port)
private void	makeBlocking(BridgePort port)
private void	makeForwarding(BridgePort port)
private void	messageAgeTimerExpiry(BridgePort port)
void	networkChanged() Indicates that the network has been modified.
private void	portStateSelection()
java.util.Vector<Packet>	processPacket(BridgePort port, Packet p) Processes a packet received by a bridge port.
private void	receivedConfigBPDU(BridgePort port, ConfigurationMessage config)
private void	receivedTCNBPDU(BridgePort port, TopologyChangeMessage tcn)
private void	recordConfigInformation(BridgePort port, ConfigurationMessage config)
private void	recordConfigTimeoutValues(ConfigurationMessage config)
void	removeFromNetwork() Removes this host from the network.
private void	reply(BridgePort port)
void	reset() Resets this bridge.
private void	rootSelection()
void	setForwardDelay(int forwardDelay) Sets the bridge Forward Delay.
void	setHelloTime(int helloTime) Sets the bridge Hello Time.
private boolean	setID(Bridge b, int newID) Sets the ID of a bridge.
boolean	setID(int newID) Sets the ID.
private static boolean	setInNetwork(Bridge b, boolean inNetwork) Updates the in network state of a bridge.
void	setMaxAge(int maxAge) Sets the bridge Max Age.
void	setPathCost(BridgePort port, int pathCost)
private boolean	superSedesPortInfo(BridgePort port, ConfigurationMessage config)
java.util.Vector<Packet>	tick() Performs one network simulation iteration.
private void	topologyChangeAcknowledged()
private void	topologyChangeDetection()
private void	topologyChangeNotificationTimerExpiry()
private void	topologyChangeTimerExpiry()
private void	transmitConfig(BridgePort port)
private void	transmitTCN()

Methods inherited from class java.lang.Object

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

Field Detail

MAX_PORTS

public static final int MAX_PORTS

The number of bridge ports to create.

See Also:

Constant Field Values

MAX_ID

public static final int MAX_ID

The maximum bridge ID.

See Also:

Constant Field Values

TIME_INCREMENT

public static final int TIME_INCREMENT

The time increment per loop iteration.

See Also:

Constant Field Values

MESSAGE_AGE_INCREMENT

private static final int MESSAGE_AGE_INCREMENT

The message age increment per hop.

See Also:

Constant Field Values

ports

public BridgePort[] ports

The bridge ports on this bridge

x

public int x

The X co-ordinate position of this bridge.

y

public int y

The X co-ordinate position of this bridge.

log

private Log log

The event log.

network

private Network network

The network this bridge is on.

queuedPackets

private java.util.Vector<Packet> queuedPackets

Packets queued to be added to the network.

hostCache

private java.util.HashMap<java.lang.Integer,Bridge.HostCacheEntry> hostCache

The host cache.

allIDs

private static boolean[] allIDs

All the bridge IDs in use.

lastAssigned

private static int lastAssigned

The last assigned bridge ID.

inNetwork

private boolean inNetwork

Whether or not this bridge is in the network.

id

private int id

Bridge's ID.

rootID

private int rootID

Current root bridge's ID.

rootPathCost

private int rootPathCost

Path cost to root.

rootPort

private BridgePort rootPort

Root port.

helloTimer

private int helloTimer

Current Hello Time timer in milliseconds.

myHelloTime

private int myHelloTime

Bridge's set Hello Time in seconds.

helloTime

private int helloTime

Hello Time set by root bridge in seconds.

myMaxAge

private int myMaxAge

Bridge's set Max Age in seconds.

maxAge

private int maxAge

Max Age set by root bridge in seconds.

myForwardDelay

private int myForwardDelay

Bridge's set Forward Delay in seconds.

forwardDelay

private int forwardDelay

Forward Delay set by root bridge in seconds.

topologyChange

private boolean topologyChange

The Topology Change flag.

topologyChangeDetected

private boolean topologyChangeDetected

The Topology Change Detected flag.

topologyChangeTimer

private int topologyChangeTimer

The Topology Change timer.

topologyChangeNotificationTimer

private int topologyChangeNotificationTimer

The Toplogy Change Notification timer.

holdTime

private static final int holdTime

The Hold Time.

See Also:

Constant Field Values

Constructor Detail

Bridge

public Bridge(int x,
              int y,
              Network network)

Creates a new Bridge.

Parameters:

x - The X co-ordinate position.

y - The Y co-ordinate position.

network - The Network this bridge is on.

Method Detail

networkChanged

public void networkChanged()

Indicates that the network has been modified.

addToNetwork

public void addToNetwork()
                  throws TooManyBridgesException

Adds this bridge to the network.

Throws:

TooManyBridgesException - If there are too many bridges on the network already.

removeFromNetwork

public void removeFromNetwork()

Removes this host from the network.

setInNetwork

private static boolean setInNetwork(Bridge b,
                                    boolean inNetwork)

Updates the in network state of a bridge.

Parameters:

b - The Bridge to modify.

inNetwork - Whether or not the host is in the network or not.

Returns:

true if the action was successful.

findFreeID

private static int findFreeID()

Finds an unused bridge ID.

Returns:

The next free bridge ID.

getID

public int getID()

Gets the ID.

Returns:

This bridge's ID.

setID

public boolean setID(int newID)

Sets the ID.

Parameters:

newID - The new ID for the bridge.

Returns:

true if the ID is not already in use.

setID

private boolean setID(Bridge b,
                      int newID)

Sets the ID of a bridge.

Parameters:

b - The Bridge to modify.

newID - The new ID of the bridge.

Returns:

true if the ID is not already in use.

getRootID

public int getRootID()

Gets the root ID.

Returns:

The root ID as seen by this bridge.

getNetworkHelloTime

public int getNetworkHelloTime()

Gets the network Hello Time.

Returns:

The Hello Time in use by the network.

getHelloTime

public int getHelloTime()

Gets the bridge Hello Time.

Returns:

The Hello Time configured for this bridge.

setHelloTime

public void setHelloTime(int helloTime)

Sets the bridge Hello Time.

Parameters:

helloTime - The Hello Time configured for this bridge.

getNetworkMaxAge

public int getNetworkMaxAge()

Gets the network Max Age.

Returns:

The Max Age in use by the network.

getMaxAge

public int getMaxAge()

Gets the bridge Max Age.

Returns:

The Max Age configured for this bridge.

setMaxAge

public void setMaxAge(int maxAge)

Sets the bridge Max Age.

Parameters:

maxAge - The Max Age configured for this bridge.

getNetworkForwardDelay

public int getNetworkForwardDelay()

Gets the network Forward Delay.

Returns:

The Forward Delay in use by the network.

getForwardDelay

public int getForwardDelay()

Gets the bridge Forward Delay.

Returns:

The Forward Delay configured for this bridge.

setForwardDelay

public void setForwardDelay(int forwardDelay)

Sets the bridge Forward Delay.

Parameters:

forwardDelay - The Forward Delay configured for this bridge.

getHostCache

public java.util.HashMap<java.lang.Integer,Bridge.HostCacheEntry> getHostCache()

Gets the host cache.

Returns:

The current host cache.

getLog

public java.lang.String[] getLog()

Gets the log entries for this bridge.

Returns:

The log as an array of strings.

reset

public void reset()

Resets this bridge.

tick

public java.util.Vector<Packet> tick()

Performs one network simulation iteration.

Returns:

Any new packets that the processing caused.

processPacket

public java.util.Vector<Packet> processPacket(BridgePort port,
                                              Packet p)

Processes a packet received by a bridge port.

Parameters:

port - The BridgePort the packet was received on.

p - The Packet to process.

Returns:

Any new packets that the processing caused.

transmitConfig

private void transmitConfig(BridgePort port)

superSedesPortInfo

private boolean superSedesPortInfo(BridgePort port,
                                   ConfigurationMessage config)

recordConfigInformation

private void recordConfigInformation(BridgePort port,
                                     ConfigurationMessage config)

recordConfigTimeoutValues

private void recordConfigTimeoutValues(ConfigurationMessage config)

configBPDUGeneration

private void configBPDUGeneration()

designatedPort

private boolean designatedPort(BridgePort port)

reply

private void reply(BridgePort port)

transmitTCN

private void transmitTCN()

configurationUpdate

private void configurationUpdate()

rootSelection

private void rootSelection()

designatedPortSelection

private void designatedPortSelection()

becomeDesignatedPort

private void becomeDesignatedPort(BridgePort bp)

portStateSelection

private void portStateSelection()

makeForwarding

private void makeForwarding(BridgePort port)

makeBlocking

private void makeBlocking(BridgePort port)

topologyChangeDetection

private void topologyChangeDetection()

topologyChangeAcknowledged

private void topologyChangeAcknowledged()

acknowledgeTopologyChange

private void acknowledgeTopologyChange(BridgePort port)

receivedConfigBPDU

private void receivedConfigBPDU(BridgePort port,
                                ConfigurationMessage config)

receivedTCNBPDU

private void receivedTCNBPDU(BridgePort port,
                             TopologyChangeMessage tcn)

helloTimerExpiry

private void helloTimerExpiry()

messageAgeTimerExpiry

private void messageAgeTimerExpiry(BridgePort port)

forwardDelayTimerExpiry

private void forwardDelayTimerExpiry(BridgePort port)

designatedForSomePort

private boolean designatedForSomePort()

topologyChangeNotificationTimerExpiry

private void topologyChangeNotificationTimerExpiry()

topologyChangeTimerExpiry

private void topologyChangeTimerExpiry()

holdTimerExpiry

private void holdTimerExpiry(BridgePort port)

initialise

public void initialise()

initialisePort

private void initialisePort(BridgePort port)

enablePort

public void enablePort(BridgePort port)

disablePort

public void disablePort(BridgePort port)

setPathCost

public void setPathCost(BridgePort port,
                        int pathCost)