use of org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.path.computation.rev200120.PathConstraints in project bgpcep by opendaylight.
the class ConstrainedShortestPathFirst method computeP2pPath.
@Override
public ConstrainedPath computeP2pPath(final VertexKey src, final VertexKey dst, final PathConstraints cts) {
LOG.info("Start CSPF Path Computation from {} to {} with constraints {}", src, dst, cts);
/* Initialize algorithm */
this.constraints = cts;
ConstrainedPathBuilder cpathBuilder = initializePathComputation(src, dst);
if (cpathBuilder.getStatus() == ComputationStatus.Failed) {
return cpathBuilder.build();
}
cpathBuilder.setBandwidth(cts.getBandwidth()).setClassType(cts.getClassType());
visitedVertices.clear();
/* Process all Connected Vertex until priority queue becomes empty. Connected Vertices are added into the
* priority queue when processing the next Connected Vertex: see relaxMC() method */
int currentCost = Integer.MAX_VALUE;
while (priorityQueue.size() != 0) {
CspfPath currentPath = priorityQueue.poll();
visitedVertices.put(currentPath.getVertexKey(), currentPath);
LOG.debug("Got path to Vertex {} from Priority Queue", currentPath.getVertex());
List<ConnectedEdge> edges = currentPath.getVertex().getOutputConnectedEdges();
for (ConnectedEdge edge : edges) {
/* Skip Connected Edges that must be prune i.e. Edges that not satisfy the given constraints,
* in particular the Bandwidth, TE Metric and Delay. */
if (pruneEdge(edge, currentPath)) {
LOG.trace(" Prune Edge {}", edge);
continue;
}
if (relaxMultiConstraints(edge, currentPath) && pathDestination.getCost() < currentCost) {
currentCost = pathDestination.getCost();
cpathBuilder.setPathDescription(getPathDescription(pathDestination.getPath())).setMetric(Uint32.valueOf(pathDestination.getCost())).setStatus(ComputationStatus.Active);
LOG.debug(" Found a valid path up to destination {}", cpathBuilder.getPathDescription());
}
}
}
/* The priority queue is empty => all the possible (vertex, path) elements have been explored
* The "ConstrainedPathBuilder" object contains the optimal path if it exists
* Otherwise an empty path with status failed is returned
*/
if (cpathBuilder.getStatus() == ComputationStatus.InProgress || cpathBuilder.getPathDescription().size() == 0) {
cpathBuilder.setStatus(ComputationStatus.Failed);
} else {
cpathBuilder.setStatus(ComputationStatus.Completed);
}
return cpathBuilder.build();
}
use of org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.path.computation.rev200120.PathConstraints in project bgpcep by opendaylight.
the class Samcra method computeP2pPath.
/* Samcra Algo:
*
* To limit the modification outside the Samcra method the same set of parameters as
* the CSPF method is used (related to pseudo code, the path length is computed inside
* the method based on the individual constraint parameters).
*
* On contrast to a simple CSPF algo, with Samcra a connected vertex might be associated to several
* metric vectors from which different path lengths are computed. However a connected vertex is only
* present once in the priority queue, associated to the minimal path weight, which is used as key
* to address the priority queue.
*
* For a given metric the path weight is an integer value computed as the entire part of
* the quantity:
* 100 * (vector_path_metric/target_metric)
* The path weight correspond to the maximum length computed from either the delay or TE metric.
*
* To maintain the priority queue behavior unchanged, a "SamcraPath" classes is created to manage
* the set of possible paths associated to a given vertex (see above).
*
*/
@Override
public ConstrainedPath computeP2pPath(final VertexKey src, final VertexKey dst, final PathConstraints cts) {
ConstrainedPathBuilder cpathBuilder;
List<ConnectedEdge> edges;
CspfPath currentPath;
LOG.info("Start SAMCRA Path Computation from {} to {} with constraints {}", src, dst, cts);
/* Initialize SAMCRA variables */
this.constraints = cts;
cpathBuilder = initializePathComputation(src, dst);
if (cpathBuilder.getStatus() == ComputationStatus.Failed) {
return cpathBuilder.build();
}
cpathBuilder.setBandwidth(cts.getBandwidth()).setClassType(cts.getClassType());
samcraPaths.clear();
samcraPaths.put(pathSource.getVertexKey(), new SamcraPath(pathSource.getVertex()));
samcraPaths.put(pathDestination.getVertexKey(), new SamcraPath(pathDestination.getVertex()));
/* Exploration of the priority queue:
* Each connected vertex is represented only once in the priority queue associated to the path
* with the minimal length (other path are stored in the SamcraPath object).
* The top of the queue, i.e. the element with the minimal key( path weight), is processed at each loop
*/
while (priorityQueue.size() != 0) {
currentPath = priorityQueue.poll();
LOG.debug(" - Process path up to Vertex {} from Priority Queue", currentPath.getVertex());
/* Prepare Samcra Path from current CSP Path except for the source */
if (!currentPath.equals(pathSource)) {
SamcraPath currentSamcraPath = samcraPaths.get(currentPath.getVertexKey());
CspfPath currentCspfPath = currentSamcraPath.getCurrentPath();
float queuePathLength = currentCspfPath.getPathLength();
LOG.trace(" - Priority Queue output SamcraPaths {} CurrentPath {} with PathLength {}", currentSamcraPath.currentPath, currentCspfPath, queuePathLength);
}
edges = currentPath.getVertex().getOutputConnectedEdges();
float currentPathLength = 1.0F;
for (ConnectedEdge edge : edges) {
/* Connected Vertex's edges processing:
* Prune the connected edges that do not satisfy the constraints (Bandwidth, TE Metric, Delay, Loss)
* For each remaining edge process the path to the remote vertex using the "relaxSamcra" procedure
*
* If the return path length is positive, the destination is reached and the
* obtained route satisfies the requested constraints.
* The path length is checked to record only the optimal route (i.e. the route with
* the minimal path length) info obtained from the destination vertex
*/
if (pruneEdge(edge, currentPath)) {
LOG.trace(" - Prune Edge {}", edge);
continue;
}
float pathLength = relaxSamcra(edge, currentPath, pathSource);
/* Check if we found a valid and better path */
if (pathLength > 0F && pathLength <= currentPathLength) {
final SamcraPath finalPath = samcraPaths.get(pathDestination.getVertexKey());
cpathBuilder.setPathDescription(getPathDescription(finalPath.getCurrentPath().getPath())).setMetric(Uint32.valueOf(finalPath.getCurrentPath().getCost())).setDelay(new Delay(Uint32.valueOf(finalPath.getCurrentPath().getDelay()))).setStatus(ComputationStatus.Active);
LOG.debug(" - Path to destination found and registered {}", cpathBuilder.getPathDescription());
currentPathLength = pathLength;
}
}
/* The connected vertex that has been removed from the priority queue may have to be re-inserted with
* the minimal length non-dominated path associated to the connected vertex if it exists (to be done
* except for the source). Otherwise, the current path associated to the connected vertex is reset to
* null to allow the connected vertex addition to the priority queue later on with a new path
* (refer to "relaxSamcra" for addition of a connected vertex to the priority queue).
*/
float previousLength = 1.0F;
CspfPath selectedPath = null;
if (!currentPath.equals(pathSource)) {
LOG.debug(" - Processing current path {} up to {} from Priority Queue", currentPath, currentPath.getVertex());
SamcraPath currentSamcraPath = samcraPaths.get(currentPath.getVertexKey());
currentSamcraPath.decrementPathCount();
/*
* The list of paths associated to the connected vertex is retrieved
* The path used to represent the connected vertex in the Priority Queue is marked from "selected"
* to "processed". The list of paths is analyzed to check if other "active" path(s) exist(s).
* If it is the case the shortest length is used to re-inject the connected vertex in the Priority Queue
*/
for (CspfPath testedPath : currentSamcraPath.getPathList()) {
LOG.debug(" - Testing path {} with status {} ", testedPath, testedPath.getPathStatus());
if (testedPath.getPathStatus() == CspfPath.SELECTED) {
testedPath.setPathStatus(CspfPath.PROCESSED);
} else if (testedPath.getPathStatus() == CspfPath.ACTIVE && testedPath.getPathLength() < previousLength) {
selectedPath = testedPath;
previousLength = testedPath.getPathLength();
}
}
/* If a path is found it is marked as "selected", used as "current path" for the connected vertex
* and added to the priority queue
*/
if (selectedPath != null) {
selectedPath.setPathStatus(CspfPath.SELECTED);
currentSamcraPath.setCurrentPath(selectedPath);
priorityQueue.add(selectedPath);
LOG.debug(" - Add path {} to Priority Queue. New path count {} ", selectedPath, currentSamcraPath.getPathCount());
} else {
currentSamcraPath.setCurrentPath(null);
}
}
}
/* The priority queue is empty => all the possible (vertex, path) elements have been explored
* The "ConstrainedPathBuilder" object contains the optimal path if it exists
* Otherwise an empty path with status failed is returned
*/
if (cpathBuilder.getStatus() == ComputationStatus.InProgress || cpathBuilder.getPathDescription().size() == 0) {
cpathBuilder.setStatus(ComputationStatus.Failed);
} else {
cpathBuilder.setStatus(ComputationStatus.Completed);
}
return cpathBuilder.build();
}
use of org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.path.computation.rev200120.PathConstraints in project bgpcep by opendaylight.
the class PathComputationImpl method computeEro.
@Override
public Ero computeEro(final EndpointsObj endpoints, final Bandwidth bandwidth, final ClassType classType, final List<Metrics> metrics, final boolean segmentRouting) {
VertexKey source = getSourceVertexKey(endpoints);
VertexKey destination = getDestinationVertexKey(endpoints);
if (source == null) {
return null;
}
if (destination == null) {
return null;
}
/* Create new Constraints Object from the request */
PathConstraints cts = getConstraints(endpoints, bandwidth, classType, metrics, segmentRouting);
/* Determine Path Computation Algorithm according to parameters */
AlgorithmType algoType;
if (cts.getTeMetric() == null && cts.getDelay() == null && cts.getBandwidth() == null) {
algoType = AlgorithmType.Spf;
} else if (cts.getDelay() == null) {
algoType = AlgorithmType.Cspf;
} else {
algoType = AlgorithmType.Samcra;
}
PathComputationAlgorithm algo = algoProvider.getPathComputationAlgorithm(tedGraph, algoType);
if (algo == null) {
return null;
}
/*
* Request Path Computation for given source, destination and
* constraints
*/
final ConstrainedPath cpath = algo.computeP2pPath(source, destination, cts);
LOG.info("Computed ERO: {}", cpath.getPathDescription());
/* Check if we got a valid Path and return appropriate ERO */
if (cpath.getStatus() == ComputationStatus.Completed) {
return MessagesUtil.getEro(cpath.getPathDescription());
} else {
return null;
}
}
use of org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.path.computation.rev200120.PathConstraints in project bgpcep by opendaylight.
the class ShortestPathFirst method computeP2pPath.
@Override
public ConstrainedPath computeP2pPath(final VertexKey src, final VertexKey dst, final PathConstraints cts) {
ConstrainedPathBuilder cpathBuilder;
List<ConnectedEdge> edges;
CspfPath currentPath;
int currentCost = Integer.MAX_VALUE;
LOG.info("Start SPF Path Computation from {} to {} with constraints {}", src, dst, cts);
/* Initialize algorithm */
this.constraints = cts;
cpathBuilder = initializePathComputation(src, dst);
if (cpathBuilder.getStatus() == ComputationStatus.Failed) {
LOG.warn("Initial configurations are not met. Abort!");
return cpathBuilder.build();
}
visitedVertices.clear();
while (priorityQueue.size() != 0) {
currentPath = priorityQueue.poll();
visitedVertices.put(currentPath.getVertexKey(), currentPath);
LOG.debug("Process path to Vertex {} from Priority Queue", currentPath.getVertex());
edges = currentPath.getVertex().getOutputConnectedEdges();
for (ConnectedEdge edge : edges) {
/* Check that Edge point to a valid Vertex and is suitable for the Constraint Address Family */
if (pruneEdge(edge, currentPath)) {
LOG.trace(" Prune Edge {}", edge);
continue;
}
if (relax(edge, currentPath) && pathDestination.getCost() < currentCost) {
currentCost = pathDestination.getCost();
cpathBuilder.setPathDescription(getPathDescription(pathDestination.getPath())).setMetric(Uint32.valueOf(pathDestination.getCost())).setStatus(ComputationStatus.Active);
LOG.debug(" Found a valid path up to destination {}", cpathBuilder.getPathDescription());
}
}
}
/* The priority queue is empty => all the possible (vertex, path) elements have been explored
* The "ConstrainedPathBuilder" object contains the optimal path if it exists
* Otherwise an empty path with status failed is returned
*/
if (cpathBuilder.getStatus() == ComputationStatus.InProgress || cpathBuilder.getPathDescription().size() == 0) {
cpathBuilder.setStatus(ComputationStatus.Failed);
} else {
cpathBuilder.setStatus(ComputationStatus.Completed);
}
return cpathBuilder.build();
}
use of org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.path.computation.rev200120.PathConstraints in project bgpcep by opendaylight.
the class PathComputationImpl method getConstraints.
private static PathConstraints getConstraints(final EndpointsObj endpoints, final Bandwidth bandwidth, final ClassType classType, final List<Metrics> metrics, final boolean segmentRouting) {
ConstraintsBuilder ctsBuilder = new ConstraintsBuilder();
Float convert;
/* Set Metrics if any */
if (metrics != null) {
for (Metrics metric : metrics) {
convert = ByteBuffer.wrap(metric.getMetric().getValue().getValue()).getFloat();
final long value = convert.longValue();
/* Skip Metric with value equal to 0 */
if (value == 0) {
continue;
}
switch(metric.getMetric().getMetricType().intValue()) {
case MessagesUtil.IGP_METRIC:
ctsBuilder.setMetric(Uint32.valueOf(value));
break;
case MessagesUtil.TE_METRIC:
ctsBuilder.setTeMetric(Uint32.valueOf(value));
break;
case MessagesUtil.PATH_DELAY:
ctsBuilder.setDelay(new Delay(Uint32.valueOf(value)));
break;
default:
LOG.warn("Metric {} is not handle by Path Computation Constraints", metric);
break;
}
}
}
/* Set Bandwidth and Class Type */
if (bandwidth != null) {
convert = ByteBuffer.wrap(bandwidth.getBandwidth().getValue()).getFloat();
final long value = convert.longValue();
/* Skip Bandwidth with value equal to 0 */
if (value != 0) {
ctsBuilder.setBandwidth(new DecimalBandwidth(BigDecimal.valueOf(value)));
if (classType != null) {
ctsBuilder.setClassType(classType.getClassType().getValue());
}
}
}
/* Set Address Family */
if (endpoints.getAddressFamily() instanceof Ipv4Case) {
ctsBuilder.setAddressFamily(segmentRouting ? AddressFamily.SrIpv4 : AddressFamily.Ipv4);
} else {
ctsBuilder.setAddressFamily(segmentRouting ? AddressFamily.SrIpv6 : AddressFamily.Ipv6);
}
return ctsBuilder.build();
}
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