public void bellmanFord(
HashMap<String, HashMap<String, Integer>> adjMatrix,
Host src,
HashMap<String, String> predecessors,
HashMap<String, Integer> fwdingToSrcPorts,
HashMap<String, Integer> distances) {
if (src.getSwitch() == null) return;
for (Host host : this.getHosts()) {
distances.put(host.getName(), this.INFINITY);
if (host.getSwitch() != null) {
// predecessors.put(host.getName(), host.getSwitch().getStringId());
// fwdingToSrcPorts.put(host.getName(), host.getPort());
}
}
for (IOFSwitch sw : this.getSwitches().values()) {
String swIdName = String.valueOf(sw.getId());
distances.put(swIdName, this.INFINITY);
}
distances.put(src.getName(), 0);
predecessors.put(src.getName(), String.valueOf(src.getSwitch().getId()));
// fwdingToSrcPorts.put(src.getName(), src.getPort());
Set<String> allDeviceNames = this.adjMatrix.keySet();
if (debug_level < 1) {
System.out.println("BF : adjMetrix keyset size : " + allDeviceNames.size());
System.out.println("Num Links : " + this.getLinks().size());
}
for (int i = 0; i < allDeviceNames.size(); i++) {
// for each u, v
for (String device : allDeviceNames) {
for (Map.Entry<String, Integer> adjEntry : adjMatrix.get(device).entrySet()) {
// for each v adjacent to u
if (adjEntry.getValue() == 1) // 1 only if it is an edge
{
if ((distances.get(device) + 1) < distances.get(adjEntry.getKey())) {
distances.put(adjEntry.getKey(), (distances.get(device) + 1));
predecessors.put(adjEntry.getKey(), device);
// fwding ports need to be populated only if it is a switch
// case 1 : this switch's predecessor is the src
if (device.equals(src.getName())) {
fwdingToSrcPorts.put(adjEntry.getKey(), src.getPort());
}
// case 2 : this switch's predecessor is another switch
else {
for (Link link : this.getLinks()) {
if (String.valueOf(link.getDst()).equals(device)) {
if (String.valueOf(link.getSrc()).equals(adjEntry.getKey())) {
fwdingToSrcPorts.put(adjEntry.getKey(), link.getSrcPort());
}
}
}
}
}
}
}
}
}
if (debug_level < 2) displayBellmanFord(src, predecessors, fwdingToSrcPorts, distances);
}
public HashMap<String, HashMap<String, Integer>> createAdjMatrix() {
HashMap<String, HashMap<String, Integer>> adjMatrix =
new HashMap<String, HashMap<String, Integer>>();
List<String> allDeviceNames = new ArrayList<String>();
for (Host host : this.getHosts()) {
allDeviceNames.add(host.getName());
}
for (IOFSwitch sw : this.getSwitches().values()) {
allDeviceNames.add(String.valueOf(sw.getId()));
}
// use list of both switch names and host names to create table
for (String hostName : allDeviceNames) {
adjMatrix.put(hostName, new HashMap<String, Integer>());
}
for (HashMap<String, Integer> internalMap : adjMatrix.values()) {
for (String hostName : allDeviceNames) {
internalMap.put(hostName, 0);
}
}
// Insert real values of 1s
for (Host host : this.getHosts()) {
if (host.getSwitch() != null) {
String switchName = String.valueOf(host.getSwitch().getId());
Map<String, Integer> internalMap;
internalMap = adjMatrix.get(host.getName());
internalMap.put(switchName, 1);
internalMap = adjMatrix.get(switchName);
internalMap.put(host.getName(), 1);
}
}
for (Link link : this.getLinks()) {
if (debug_level < 2)
System.out.println("Link src: " + link.getSrc() + " dest: " + link.getDst());
String switchId1 = String.valueOf(link.getSrc());
String switchId2 = String.valueOf(link.getDst());
if (adjMatrix.get(switchId1) != null) {
adjMatrix.get(switchId1).put(switchId2, 1);
} else {
System.out.println("Looks like s" + switchId1 + " is no longer up");
}
if (adjMatrix.get(switchId2) != null) adjMatrix.get(switchId2).put(switchId1, 1);
else System.out.println("Looks like s" + switchId2 + " is no longer up");
}
return adjMatrix;
}
private void displayBellmanFord(
Host src,
HashMap<String, String> predecessors,
HashMap<String, Integer> fwdingToSrcPorts,
HashMap<String, Integer> distances) {
try {
System.out.println(
"\nBELLMAN FORD : src : "
+ src.getName()
+ " "
+ IPv4.fromIPv4Address(src.getIPv4Address()));
System.out.print("Predecessors : ");
for (Entry<String, String> predMapEntry : predecessors.entrySet()) {
System.out.print("(" + predMapEntry.getKey() + "," + predMapEntry.getValue() + ") ");
}
System.out.println();
System.out.print("FwdPorts : ");
for (Entry<String, Integer> mapEntry : fwdingToSrcPorts.entrySet()) {
System.out.print("(" + mapEntry.getKey() + "," + mapEntry.getValue() + ") ");
}
System.out.println();
System.out.print("Distances : ");
for (Entry<String, Integer> mapEntry : distances.entrySet()) {
System.out.print("(" + mapEntry.getKey() + "," + mapEntry.getValue() + ") ");
}
System.out.println();
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* Event handler called when a host joins the network.
*
* @param device information about the host
*/
@Override
public void deviceAdded(IDevice device) {
Host host = new Host(device, this.floodlightProv);
// We only care about a new host if we know its IP
if (host.getIPv4Address() != null) {
log.info(String.format("Host %s added", host.getName()));
this.knownHosts.put(device, host);
/** ************************************************************** */
/* TODO: Update routing: add rules to route to new host */
if (host.isAttachedToSwitch() != false) {
// TODO : adbhat : install rules to route traffic to this host
updateAllRouting();
// else nothing
/** ************************************************************** */
}
}
}
/**
* Event handler called when a host moves within the network.
*
* @param device information about the host
*/
@Override
public void deviceMoved(IDevice device) {
Host host = this.knownHosts.get(device);
if (null == host) {
host = new Host(device, this.floodlightProv);
this.knownHosts.put(device, host);
}
if (!host.isAttachedToSwitch()) {
this.deviceRemoved(device);
return;
}
log.info(
String.format(
"Host %s moved to s%d:%d", host.getName(), host.getSwitch().getId(), host.getPort()));
/** ****************************************************************** */
/* TODO: Update routing: change rules to route to host */
updateAllRouting();
/** ****************************************************************** */
}
/**
* Event handler called when a host is no longer attached to a switch.
*
* @param device information about the host
*/
@Override
public void deviceRemoved(IDevice device) {
Host host = this.knownHosts.get(device);
if (null == host) {
return;
}
this.knownHosts.remove(host);
log.info(String.format("Host %s is no longer attached to a switch", host.getName()));
/** ****************************************************************** */
/* TODO: Update routing: remove rules to route to host */
OFMatch matchCriteria = new OFMatch();
matchCriteria.setDataLayerType(OFMatch.ETH_TYPE_IPV4);
matchCriteria.setNetworkDestination(host.getIPv4Address());
for (IOFSwitch currSw : this.getSwitches().values()) {
SwitchCommands.removeRules(currSw, this.table, matchCriteria);
}
/** ****************************************************************** */
}
public void bellmanFordOld(
HashMap<String, HashMap<String, Integer>> adjMatrix,
Host src,
HashMap<String, String> predecessors,
HashMap<String, Integer> fwdingToSrcPorts,
HashMap<String, Integer> distances) {
if (src.getSwitch() == null) return;
for (Host host : this.getHosts()) {
distances.put(host.getName(), this.INFINITY);
if (host.getSwitch() != null) {
predecessors.put(host.getName(), String.valueOf(host.getSwitch().getId()));
fwdingToSrcPorts.put(host.getName(), host.getPort());
}
}
for (long swId : this.getSwitches().keySet()) {
String swIdName = String.valueOf(swId);
distances.put(swIdName, this.INFINITY);
}
distances.put(src.getName(), 0);
predecessors.put(src.getName(), String.valueOf(src.getSwitch().getId()));
fwdingToSrcPorts.put(src.getName(), src.getPort());
Set<String> allDeviceNames = this.adjMatrix.keySet();
for (int i = 0; i < allDeviceNames.size() - 1; i++) {
// for each u
// for (Link link : this.getLinks())
// {
// System.out.println("Link Src: " + link.getSrc() + "\t" + link.getDst());
// if(distances.get(String.valueOf(link.getSrc())) + 1 <
// distances.get(String.valueOf(link.getDst())))
// {
// distances.put(String.valueOf(link.getDst()), distances.get(String.valueOf(link.getSrc())) +
// 1);
// predecessors.put(String.valueOf(link.getDst()), String.valueOf(link.getSrc()));
// fwdingToSrcPorts.put(String.valueOf(link.getDst()), link.getDstPort());
// }
// }
}
if (debug_level < 2) displayBellmanFord(src, predecessors, fwdingToSrcPorts, distances);
}
private void updateAllRouting() {
if (debug_level < 2)
System.out.println("\n**************Entering Update all Routing..**********************");
this.adjMatrix = null;
this.adjMatrix = this.createAdjMatrix();
for (Host host : this.getHosts()) {
// find shortest path to host - come from BF
HashMap<String, String> predecessors = new HashMap<String, String>();
HashMap<String, Integer> fwdingToSrcPorts = new HashMap<String, Integer>();
HashMap<String, Integer> distances = new HashMap<String, Integer>();
bellmanFord(adjMatrix, host, predecessors, fwdingToSrcPorts, distances);
for (Host otherHost : this.getHosts()) {
// foreach otherhost,
if (debug_level < 2)
System.out.println(
"Tracing path from host : " + otherHost.getName() + " to " + host.getName());
if (otherHost == host) {
continue;
}
IOFSwitch currSw = otherHost.getSwitch();
if (currSw == null) {
if (debug_level < 2)
System.out.println("Host " + otherHost.getName() + " not connected to any switch");
continue;
}
String currSwId;
// for each switch in the path to this host
while (currSw != null) {
// install rule on currSw
if (debug_level < 1) System.out.println("currSw: " + String.valueOf(currSw.getId()));
currSwId = String.valueOf(currSw.getId());
if (fwdingToSrcPorts.get(currSwId) == null) {
if (debug_level < 1)
System.out.println(
"currSw "
+ String.valueOf(currSw.getId())
+ " has no further fwdToSrcPort entry");
break;
}
int opPortTowardsSrc = fwdingToSrcPorts.get(currSwId);
installL3FwdRule(currSw, host, opPortTowardsSrc);
// currSw = predecessor.get(currSw);
currSwId = predecessors.get(String.valueOf(currSw.getId()));
if (currSwId.equals(host.getName())) {
if (debug_level < 1)
System.out.println(
"currSw "
+ String.valueOf(currSw.getId())
+ " has no further predecessor, directly connected to host");
break;
}
currSw = this.getSwitches().get(Long.parseLong(currSwId));
if (currSw == null) {
if (debug_level < 1)
System.out.println("end of path since updated currSw for" + currSwId + " is null");
}
}
}
}
if (debug_level < 2) displayAdjMatrix();
}