be.ac.ulg.montefiore.run.totem.domain.model.impl
Class DiffServBandwidthManagement

java.lang.Object
  be.ac.ulg.montefiore.run.totem.domain.model.impl.DiffServBandwidthManagement

All Implemented Interfaces:

BandwidthManagement

Direct Known Subclasses:

DiffServBandwidthManagementSnapshot

public class DiffServBandwidthManagement
extends java.lang.Object
implements BandwidthManagement

This class manages link bandwidth. Adding or removing lsps changes the reserved bandwidth on the links.
This implementation uses preemption. it also uses Diffserv model to update link reservable bandwidth.

Creation date: 3/11/2006

Author:

Gaël Monfort (monfort@run.montefiore.ulg.ac.be)

Field Summary

protected Domain

domain

Constructor Summary

DiffServBandwidthManagement(Domain domain)
Create a new DiffServBandwidthManagement object to use with the given domain.

Method Summary

void	addLsp(Lsp lsp) Add lsp reservation.
protected void	addReservation(Link link, float bw, int prio) Add some reservation to the given link.
java.util.List<Lsp>	getPreemptList(Lsp lsp) Returns the list of lsps to be preempted when a lsp is to be added to the domain.
protected float[]	getRbw(Link link) Return the rbw array associated with the given link.
float	getReservableBandwidth(int priority, Link link, java.util.Collection<Link> protectedLinks) Returns the maximum reservable bandwidth at priority level priority for a lsp traversing the link link.
protected float	getReservedBandwidth(Link link) Returns the total reserved bandwidth among all classtypes.
DiffServBandwidthManagementSnapshot	getSnapshot() Returns a snapshot of the reservation in the domain.
void	init() Initialise the Bandwidth Management object with the lsps already present in the domain.
protected boolean	lspCanBeEstablished(Link link, int priority, float reservation) Perform admission control for preemption on link link for an lsp to be established at priority priority with reservation bandwidth.
void	recomputeRbw(Link link) Recompute the reservable bandwidth (rbw array) of the link link by using the lsps established in the domain. Warning: all rbw values should be set to 0 before calling this method.
void	removeLsp(Lsp lsp) Removes lsp reservation.
protected void	removeReservation(Link link, float bw, int prio) Remove some reservation to the given link.
boolean	usePreemption() returns true.

Methods inherited from class java.lang.Object

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

Field Detail

domain

protected Domain domain

Constructor Detail

DiffServBandwidthManagement

public DiffServBandwidthManagement(Domain domain)

Create a new DiffServBandwidthManagement object to use with the given domain.

Parameters:

domain -

Method Detail

init

public void init()
          throws LinkCapacityExceededException

Initialise the Bandwidth Management object with the lsps already present in the domain. This must be called prior to use.

Specified by:

init in interface BandwidthManagement

Throws:

LinkCapacityExceededException - if the calculated bandwidth exceed link capacity

getRbw

protected float[] getRbw(Link link)

Return the rbw array associated with the given link.

Parameters:

link -

Returns:

addReservation

protected void addReservation(Link link,
                              float bw,
                              int prio)
                       throws LinkCapacityExceededException

Add some reservation to the given link.

Parameters:

link -

bw -

prio -

Throws:

LinkCapacityExceededException

removeReservation

protected void removeReservation(Link link,
                                 float bw,
                                 int prio)
                          throws LinkCapacityExceededException

Remove some reservation to the given link.

Parameters:

link -

bw -

prio -

Throws:

LinkCapacityExceededException

getPreemptList

public java.util.List<Lsp> getPreemptList(Lsp lsp)
                                   throws LinkCapacityExceededException

Returns the list of lsps to be preempted when a lsp is to be added to the domain.
Preemption is done in all classtypes. For each link of the lsp to add, from the least preemption level, it tries to find one lsp to preempt to get enough bandwidth. If it cannot be found, all lsps at this preemption level are preempted until enough bandwidth is freed on the link. It then cycles through all preemption levels lower than the lsp one. If a lsp frees no bandwidth at all when preempted (in another class type), it is not preempted at all.

Specified by:

getPreemptList in interface BandwidthManagement

Parameters:

lsp - the Lsp to be added to the domain

Returns:

Throws:

LinkCapacityExceededException

lspCanBeEstablished

protected boolean lspCanBeEstablished(Link link,
                                      int priority,
                                      float reservation)

Perform admission control for preemption on link link for an lsp to be established at priority priority with reservation bandwidth.

There must be enough reservable bandwidth in the lsp classtype at the min priority value and the total reserved bandwidth on the link should not exceed the link max reservable bandwidth.

Parameters:

link -

priority -

reservation -

Returns:

addLsp

public void addLsp(Lsp lsp)
            throws LinkCapacityExceededException

Add lsp reservation. It adds some reservation to the links in the path of the lsp.

Specified by:

addLsp in interface BandwidthManagement

Parameters:

lsp -

Throws:

LinkCapacityExceededException - If not enough bandwidth is available

removeLsp

public void removeLsp(Lsp lsp)
               throws LinkCapacityExceededException

Removes lsp reservation. It removes some reservation to the links in the path of the lsp.

Specified by:

removeLsp in interface BandwidthManagement

Parameters:

lsp -

Throws:

LinkCapacityExceededException

usePreemption

public boolean usePreemption()

returns true. This class manages preemption.

Specified by:

usePreemption in interface BandwidthManagement

Returns:

getReservableBandwidth

public float getReservableBandwidth(int priority,
                                    Link link,
                                    java.util.Collection<Link> protectedLinks)

Returns the maximum reservable bandwidth at priority level priority for a lsp traversing the link link. If protectedLinks is given, the reservable bandwidth for a backup lsp protecting those links is returned, otherwise, a primary lsp is assumed.
Obtain the reservable bandwidth from the Diffserv model associated with the link.

Specified by:

getReservableBandwidth in interface BandwidthManagement

Parameters:

priority -

link -

protectedLinks -

Returns:

getReservedBandwidth

protected float getReservedBandwidth(Link link)

Returns the total reserved bandwidth among all classtypes.

Returns:

recomputeRbw

public void recomputeRbw(Link link)
                  throws LinkCapacityExceededException

Recompute the reservable bandwidth (rbw array) of the link link by using the lsps established in the domain.
Warning: all rbw values should be set to 0 before calling this method.

Specified by:

recomputeRbw in interface BandwidthManagement

Parameters:

link -

Throws:

LinkCapacityExceededException

getSnapshot

public DiffServBandwidthManagementSnapshot getSnapshot()

Returns a snapshot of the reservation in the domain. Adding and removing LSPs to the snapshot will not affect the reservation of the links.

Specified by:

getSnapshot in interface BandwidthManagement

Returns: