public void AdmitNewCallToOngoingSession(ISession session, ICall call, IMobileTerminal mobileTerminal)
{
if (session == null)
{
throw new VerticalHandoverPredictionException($"{nameof(session)} is invalid");
}
if (call == null)
{
throw new VerticalHandoverPredictionException($"{nameof(call)} is invalid");
}
if (mobileTerminal == null)
{
throw new VerticalHandoverPredictionException($"{nameof(mobileTerminal)} is invalid");
}
TakeNetworkResources(call.Service.ComputeRequiredNetworkResources());
session.AddToActiveCalls(call);
var state = mobileTerminal.UpdateMobileTerminalStateWhenAdmitingNewCallToOngoingSession(session.ActiveCalls);
session.AddToSessionSequence(state);
}
public bool CanAdmitNewCallToOngoingSession(ISession session, ICall call, IMobileTerminal mobileTerminal)
{
if (session == null)
{
throw new VerticalHandoverPredictionException($"{nameof(session)} is invalid");
}
if (call == null)
{
throw new VerticalHandoverPredictionException($"{nameof(call)} is invalid");
}
if (mobileTerminal == null)
{
throw new VerticalHandoverPredictionException($"{nameof(mobileTerminal)} is invalid");
}
if (!this.Services.Contains(call.Service))
{
return(false);
}
var requiredNetworkResources = call.Service.ComputeRequiredNetworkResources();
return(requiredNetworkResources <= AvailableNetworkResources());
}
private void StartNewSessionAndAdmitCall(CallStartedEvent evt, IMobileTerminal mobileTerminal, IRat rat)
{
var session = new Session(rat.RatId, evt.Time);
mobileTerminal.SetSessionId(session.SessionId);
rat.TakeNetworkResources(evt.Call.Service.ComputeRequiredNetworkResources());
session.AddToActiveCalls(evt.Call);
var state = mobileTerminal.UpdateMobileTerminalState(session);
session.AddToSessionSequence(state);
rat.AddSession(session);
}
private void RunNonPredictiveAlgorithm(CallStartedEvent evt, IMobileTerminal mobileTerminal)
{
var rats = HetNet.Instance.Rats
.Where(x => x.Services.Contains(evt.Call.Service))
.OrderBy(x => x.Services.Count)
.ToList();
foreach (var rat in rats)
{
if (evt.Call.Service.ComputeRequiredNetworkResources() <= rat.AvailableNetworkResources())
{
StartNewSessionAndAdmitCall(evt, mobileTerminal, rat);
return;
}
}
HetNet.Instance.BlockedCalls++;
}
private void RunPredictiveAlgorithm(CallStartedEvent evt, IMobileTerminal mobileTerminal)
{
//var history = CsvUtils._Instance.Read<CallLogMap,CallLog>($"{Environment.CurrentDirectory}/calllogs.csv").ToList();
var nextState = evt.Call.Service.GetState();
if (HetNet.Instance.CallerHistory.Any())
{
var group = HetNet.Instance.CallerHistory
.Where(x => x.UserId == mobileTerminal.MobileTerminalId)
.Select(x => x.SessionSequence)
.Select(x => x.ToList().Select(x => (MobileTerminalState)(int.Parse(x.ToString()))))
.Select(x => x.Skip(1).Take(2))
.Where(x => x.StartsWith(new List <MobileTerminalState> {
evt.Call.Service.GetState()
}))
.SelectMany(x => x.Skip(1))
.Where(x => x != MobileTerminalState.Idle)
.GroupBy(x => x);
//If group is empty it means prediction has failed
if (!group.Any())
{
HetNet.Instance.FailedPredictions++;
}
else
{
//continue to compute frequency table
var prediction = default(IGrouping <MobileTerminalState, MobileTerminalState>);
var max = 0;
//If There are ties it takes the last item in the history : Fix this, what decision is made in that case
//group.Dump();
foreach (var grp in group)
{
if (grp.Count() > max)
{
prediction = grp;
max = prediction.Count();
}
//Console.WriteLine( $"next state is {grp.Key}, Frequency: {grp.Count()}");
}
nextState = prediction.Key;
}
}
var services = new List <Service> {
evt.Call.Service
};
foreach (var service in nextState.SupportedServices())
{
if (!services.Contains(service))
{
services.Add(service);
}
}
var rats = HetNet.Instance.Rats
.Where(x => x.Services.ToHashSet().IsSupersetOf(services))
.OrderBy(x => x.Services.Count)
.ToList();
//This scheme reserves bandwidth in advance, I considered all the services
var requiredNetworkResources = 0;
foreach (var service in services)
{
requiredNetworkResources += service.ComputeRequiredNetworkResources();
}
foreach (var rat in rats)
{
if (requiredNetworkResources <= rat.AvailableNetworkResources())
{
StartNewSessionAndAdmitCall(evt, mobileTerminal, rat);
if (evt.Call.Service.GetState() != nextState)
{
//Successful Prediction means 1. predicted state was not idle 2. call ends up being admited as predicted
HetNet.Instance.SuccessfulPredictions++;
//Log.Information("----- Successful prediction");
}
return;
}
}
//All Possible Rats Cannot Admit Call i.e [call in its predicted state]
HetNet.Instance.BlockedUsingPredictiveScheme++;
//Try just accommodating the incoming call without predicting before blocking it
RunNonPredictiveAlgorithm(evt, mobileTerminal);
}
public void Handover(ICall call, ISession session, IMobileTerminal mobileTerminal, IRat source)
{
if (call == null)
{
throw new VerticalHandoverPredictionException($"{nameof(call)} is invalid");
}
if (session == null)
{
throw new VerticalHandoverPredictionException($"{nameof(session)} is invalid");
}
if (mobileTerminal == null)
{
throw new VerticalHandoverPredictionException($"{nameof(mobileTerminal)} is invalid");
}
if (source == null)
{
throw new VerticalHandoverPredictionException($"{nameof(source)} is invalid");
}
var callsToHandedOverToTargetRat = session.ActiveCalls.Select(x => x.Service).ToList();
callsToHandedOverToTargetRat.Add(call.Service);
var rats = Rats
.Where(x => x.RatId != session.RatId &&
x.Services.ToHashSet().IsSupersetOf(callsToHandedOverToTargetRat))
.OrderBy(x => x.Services.Count())
.ToList();
var requiredNetworkResouces = 0;
foreach (var service in callsToHandedOverToTargetRat)
{
requiredNetworkResouces += service.ComputeRequiredNetworkResources();
}
foreach (var target in rats)
{
if (requiredNetworkResouces <= target.AvailableNetworkResources())
{
UpdateHandovers(call.Service);
source.RealeaseNetworkResources(requiredNetworkResouces - call.Service.ComputeRequiredNetworkResources());
source.RemoveSession(session);
session.SetRatId(target.RatId);
target.TakeNetworkResources(requiredNetworkResouces);
session.AddToActiveCalls(call);
var state = mobileTerminal.UpdateMobileTerminalState(session);
session.AddToSessionSequence(state);
target.AddSession(session);
return;
}
}
//If call cannot be handed over then the incoming call is blocked
BlockedCalls++;
}
