[HICN-442] new forwarding strategy

Signed-off-by: michele papalini <micpapal@cisco.com>
Change-Id: I62c03bddedc83e523fc60f4b50d2c69e38b50318
Signed-off-by: Angelo Mantellini <angelo.mantellini@cisco.com>
Signed-off-by: michele papalini <micpapal@cisco.com>

6 files changed, 90 insertions, 79 deletions

diff --git a/hicn-light/src/hicn/processor/fib.c b/hicn-light/src/hicn/processor/fib.c
index c67bc6773..8822134fe 100644
--- a/hicn-light/src/hicn/processor/fib.c
+++ b/hicn-light/src/hicn/processor/fib.c
@@ -200,8 +200,10 @@ void fib_Add(FIB *fib, FibEntry *entry) {
   nameBitvector_clear(name_GetContentName(inner_prefix), match_len);
   name_setLen(inner_prefix,  match_len);
 
-  FibEntry * inner_entry = fibEntry_Create(inner_prefix, SET_STRATEGY_LOADBALANCER,
-            fib->forwarder);
+  //this is an inner node, we don't want an acctive strategy
+  //like low_latency that sends probes in this node
+  FibEntry * inner_entry = fibEntry_Create(inner_prefix,
+            SET_STRATEGY_LOADBALANCER, fib->forwarder);
 
   FibNode * inner_node = _createNode(NULL, NULL, inner_entry, false);
   FibNode * new_node = _createNode(NULL, NULL, entry, true);
diff --git a/hicn-light/src/hicn/processor/fib.h b/hicn-light/src/hicn/processor/fib.h
index 7507bb85c..ef9e121b8 100644
--- a/hicn-light/src/hicn/processor/fib.h
+++ b/hicn-light/src/hicn/processor/fib.h
@@ -23,7 +23,7 @@
 struct fib;
 typedef struct fib FIB;
 
-FIB *fib_Create();
+FIB *fib_Create(Forwarder *forwarder);
 
 void fib_Destroy(FIB **fibPtr);
 
diff --git a/hicn-light/src/hicn/processor/fibEntry.c b/hicn-light/src/hicn/processor/fibEntry.c
index fe32ada8d..be7278987 100644
--- a/hicn-light/src/hicn/processor/fibEntry.c
+++ b/hicn-light/src/hicn/processor/fibEntry.c
@@ -22,9 +22,8 @@
 #include <hicn/core/nameBitvector.h>
 
 #include <hicn/strategies/loadBalancer.h>
-#include <hicn/strategies/loadBalancerWithPD.h>
+#include <hicn/strategies/lowLatency.h>
 #include <hicn/strategies/rnd.h>
-#include <hicn/strategies/rndSegment.h>
 #include <hicn/strategies/strategyImpl.h>
 #ifdef WITH_MAPME
 #include <parc/algol/parc_HashMap.h>
@@ -80,34 +79,23 @@ FibEntry *fibEntry_Create(Name *name, strategy_type fwdStrategy) {
                     sizeof(FibEntry));
   fibEntry->name = name_Acquire(name);
 
-  if (fwdStrategy) {
-    switch (fwdStrategy) {
-      case SET_STRATEGY_LOADBALANCER:
-        fibEntry->fwdStrategy = strategyLoadBalancer_Create();
-        break;
-
-      case SET_STRATEGY_RANDOM:
-        fibEntry->fwdStrategy = strategyRnd_Create();
-        break;
-
-      case SET_STRATEGY_RANDOM_PER_DASH_SEGMENT:
-        fibEntry->fwdStrategy = strategyRndSegment_Create();
-        break;
-
-      case SET_STRATEGY_LOADBALANCER_WITH_DELAY:
-        fibEntry->fwdStrategy = strategyLoadBalancerWithPD_Create();
-        break;
-
-      default:
-        // LB is the default strategy
-        fibEntry->fwdStrategy = strategyLoadBalancer_Create();
-        // the LB strategy is the default one
-        // other strategies can be set using the appropiate function
-        break;
-    }
+  switch (fwdStrategy) {
+    case SET_STRATEGY_LOADBALANCER:
+      fibEntry->fwdStrategy = strategyLoadBalancer_Create();
+      break;
 
-  } else {
-    fibEntry->fwdStrategy = strategyLoadBalancer_Create();
+    case SET_STRATEGY_RANDOM:
+      fibEntry->fwdStrategy = strategyRnd_Create();
+
+    case SET_STRATEGY_LOW_LATENCY:
+      fibEntry->fwdStrategy = strategyLowLatency_Create();
+      break;
+
+    default:
+      // LB is the default strategy
+      fwdStrategy = SET_STRATEGY_LOADBALANCER;
+      fibEntry->fwdStrategy = strategyLoadBalancer_Create();
+      break;
   }
 
   fibEntry->refcount = 1;
@@ -124,6 +112,10 @@ FibEntry *fibEntry_Create(Name *name, strategy_type fwdStrategy) {
   fibEntry->policy_counters = POLICY_COUNTERS_NONE;
 #endif /* WITH_POLICY */
 
+  if(fwdStrategy == SET_STRATEGY_LOW_LATENCY){
+    strategyLowLatency_SetStrategy(fibEntry->fwdStrategy,
+                                     fibEntry->forwarder, fibEntry);
+  }
   return fibEntry;
 }
 
@@ -166,20 +158,20 @@ void fibEntry_SetStrategy(FibEntry *fibEntry, strategy_type strategy) {
       fwdStrategyImpl = strategyRnd_Create();
       break;
 
-    case SET_STRATEGY_RANDOM_PER_DASH_SEGMENT:
-      fwdStrategyImpl = strategyRndSegment_Create();
-      break;
-
-    case SET_STRATEGY_LOADBALANCER_WITH_DELAY:
-      fwdStrategyImpl = strategyLoadBalancerWithPD_Create();
+    case SET_STRATEGY_LOW_LATENCY:
+      fwdStrategyImpl = strategyLowLatency_Create();
       break;
 
     default:
-      // LB is the defualt strategy
+      // LB is the default strategy
+      strategy = SET_STRATEGY_LOADBALANCER;
       fwdStrategyImpl = strategyLoadBalancer_Create();
-      // the LB strategy is the default one
-      // other strategies can be set using the appropiate function
       break;
+    }
+
+  if(strategy == SET_STRATEGY_LOW_LATENCY){
+    strategyLowLatency_SetStrategy(fwdStrategyImpl,
+                                    fibEntry->forwarder, fibEntry);
   }
 
   const NumberSet *nexthops = fibEntry_GetNexthops(fibEntry);
@@ -613,7 +605,9 @@ void fibEntry_ReceiveObjectMessage(FibEntry *fibEntry,
 void fibEntry_ReceiveObjectMessage(const FibEntry *fibEntry,
 #endif /* WITH_POLICY */
                                    const NumberSet *egressId,
-                                   const Message *objectMessage, Ticks rtt) {
+                                   const Message *objectMessage,
+                                   Ticks pitEntryCreation,
+                                   Ticks objReception) {
   parcAssertNotNull(fibEntry, "Parameter fibEntry must be non-null");
 
 #ifdef WITH_POLICY
@@ -622,6 +616,7 @@ void fibEntry_ReceiveObjectMessage(const FibEntry *fibEntry,
   /* Update statistic counters : */
 
   size_t msg_size = message_Length(objectMessage);
+  Ticks rtt = objReception - pitEntryCreation;
 
   for (unsigned i = 0; i < numberSet_Length(egressId); i++) {
     unsigned conn_id = numberSet_GetItem(egressId, i);
@@ -666,7 +661,7 @@ void fibEntry_ReceiveObjectMessage(const FibEntry *fibEntry,
 #endif /* WITH_POLICY */
 
   fibEntry->fwdStrategy->receiveObject(fibEntry->fwdStrategy, egressId,
-                                       objectMessage, rtt);
+                                       objectMessage, pitEntryCreation, objReception);
 }
 
 #ifdef WITH_POLICY
diff --git a/hicn-light/src/hicn/processor/fibEntry.h b/hicn-light/src/hicn/processor/fibEntry.h
index 7ec771b4c..1bd917bc2 100644
--- a/hicn-light/src/hicn/processor/fibEntry.h
+++ b/hicn-light/src/hicn/processor/fibEntry.h
@@ -110,7 +110,9 @@ void fibEntry_ReceiveObjectMessage(FibEntry *fibEntry,
 void fibEntry_ReceiveObjectMessage(const FibEntry *fibEntry,
 #endif /* WITH_POLICY */
                                    const NumberSet *egressId,
-                                   const Message *objectMessage, Ticks rtt);
+                                   const Message *objectMessage,
+                                   Ticks pitEntryCreation,
+                                   Ticks objReception);
 
 #ifdef WITH_POLICY
 policy_t fibEntry_GetPolicy(const FibEntry *fibEntry);
@@ -125,16 +127,10 @@ void fibEntry_OnTimeout(FibEntry *fibEntry, const NumberSet *egressId);
 const NumberSet *fibEntry_GetNexthopsFromForwardingStrategy(
     FibEntry *fibEntry, const Message *interestMessage, bool is_retransmission);
 
-void fibEntry_ReceiveObjectMessage(FibEntry *fibEntry,
-                                   const NumberSet *egressId,
-                                   const Message *objectMessage, Ticks rtt);
 #else
 void fibEntry_OnTimeout(const FibEntry *fibEntry, const NumberSet *egressId);
 const NumberSet *fibEntry_GetNexthopsFromForwardingStrategy(
     const FibEntry *fibEntry, const Message *interestMessage);
-void fibEntry_ReceiveObjectMessage(const FibEntry *fibEntry,
-                                   const NumberSet *egressId,
-                                   const Message *objectMessage, Ticks rtt);
 #endif /* WITH_POLICY */
 
 
diff --git a/hicn-light/src/hicn/processor/messageProcessor.c b/hicn-light/src/hicn/processor/messageProcessor.c
index c989f8cb6..e38a3d558 100644
--- a/hicn-light/src/hicn/processor/messageProcessor.c
+++ b/hicn-light/src/hicn/processor/messageProcessor.c
@@ -34,9 +34,8 @@
 #include <hicn/content_store/contentStoreLRU.h>
 
 #include <hicn/strategies/loadBalancer.h>
-#include <hicn/strategies/loadBalancerWithPD.h>
+#include <hicn/strategies/lowLatency.h>
 #include <hicn/strategies/rnd.h>
-#include <hicn/strategies/rndSegment.h>
 #include <hicn/strategies/strategyImpl.h>
 
 #include <hicn/io/streamConnection.h>
@@ -48,6 +47,7 @@
 #include <hicn/utils/utils.h>
 
 #include <hicn/utils/address.h>
+#include <hicn/core/messageHandler.h>
 
 #ifdef WITH_POLICY
 #define STATS_INTERVAL 1000 /* ms */
@@ -160,7 +160,7 @@ MessageProcessor *messageProcessor_Create(Forwarder *forwarder) {
   processor->logger = logger_Acquire(forwarder_GetLogger(forwarder));
   processor->pit = pitStandard_Create(forwarder);
 
-  processor->fib = fib_Create();
+  processor->fib = fib_Create(forwarder);
 
   if (logger_IsLoggable(processor->logger, LoggerFacility_Processor,
                         PARCLogLevel_Debug)) {
@@ -304,18 +304,13 @@ bool messageProcessor_AddOrUpdateRoute(MessageProcessor *processor,
       control->addressType, &control->address, &control->len);
   strategy_type fwdStrategy =
       configuration_GetForwardingStrategy(config, prefixStr);
-  if (fwdStrategy == LAST_STRATEGY_VALUE) {
-    fwdStrategy = SET_STRATEGY_LOADBALANCER;
-  }
 
   Name *prefix = name_CreateFromAddress(control->addressType, control->address,
                                         control->len);
   FibEntry *entry = fib_Contains(processor->fib, prefix);
-  bool newEntry = false;
   if (entry != NULL) {
     fibEntry_AddNexthop(entry, ifidx);
   } else {
-    newEntry = true;
 #ifdef WITH_POLICY
     entry = fibEntry_Create(prefix, fwdStrategy, processor->forwarder);
 #else
@@ -328,14 +323,6 @@ bool messageProcessor_AddOrUpdateRoute(MessageProcessor *processor,
   free(prefixStr);
   name_Release(&prefix);
 
-  /* For policy implementation, we need access to the ConnectionTable in all
-   * Forwarding Strategies, so it is setup during FIB Entry creation */
-  if (newEntry && (fwdStrategy == SET_STRATEGY_LOADBALANCER_WITH_DELAY)) {
-    strategyLoadBalancerWithPD_SetConnectionTable(
-        fibEntry_GetFwdStrategy(entry),
-        forwarder_GetConnectionTable(processor->forwarder));
-  }
-
   return true;
 }
 
@@ -365,9 +352,6 @@ bool messageProcessor_AddOrUpdatePolicy(MessageProcessor *processor,
   if (!entry) {
     strategy_type fwdStrategy =
         configuration_GetForwardingStrategy(config, prefixStr);
-    if (fwdStrategy == LAST_STRATEGY_VALUE) {
-      fwdStrategy = SET_STRATEGY_LOADBALANCER;
-    }
     entry = fibEntry_Create(prefix, fwdStrategy, processor->forwarder);
     fib_Add(processor->fib, entry);
   }
@@ -407,11 +391,6 @@ void processor_SetStrategy(MessageProcessor *processor, Name *prefix,
   FibEntry *entry = fib_Contains(processor->fib, prefix);
   if (entry != NULL) {
     fibEntry_SetStrategy(entry, strategy);
-    if (strategy == SET_STRATEGY_LOADBALANCER_WITH_DELAY) {
-      strategyLoadBalancerWithPD_SetConnectionTable(
-          fibEntry_GetFwdStrategy(entry),
-          forwarder_GetConnectionTable(processor->forwarder));
-    }
   }
 }
 
@@ -572,6 +551,34 @@ static bool messageProcessor_ForwardViaFib(MessageProcessor *processor,
     return false;
   }
 
+  if(messageHandler_IsAProbe(message_FixedHeader(interestMessage))){
+    bool reply_to_probe = false;
+    ConnectionTable * ct = forwarder_GetConnectionTable(processor->forwarder);
+    const NumberSet * nexthops = fibEntry_GetNexthops(fibEntry);
+    unsigned size = (unsigned) numberSet_Length(nexthops);
+
+    for (unsigned i = 0; i < size; i++) {
+      unsigned nhop = numberSet_GetItem(nexthops, i);
+      Connection *conn =
+          (Connection *)connectionTable_FindById(ct, nhop);
+      if (!conn)
+        continue;
+      bool isLocal = connection_IsLocal(conn);
+      if(isLocal){
+        Connection * replyConn =
+                  (Connection *)connectionTable_FindById(ct,
+                    message_GetIngressConnectionId(interestMessage));
+        connection_HandleProbe(replyConn,
+                  (uint8_t *) message_FixedHeader(interestMessage));
+        reply_to_probe = true;
+        break;
+      }
+    }
+    if(reply_to_probe)
+      return false;
+  }
+
+
   PitEntry *pitEntry = pit_GetPitEntry(processor->pit, interestMessage);
   if (pitEntry == NULL) {
     return false;
@@ -709,6 +716,20 @@ static void messageProcessor_ReceiveContentObject(MessageProcessor *processor,
                  (void *)message, processor->stats.countDroppedNoReversePath);
     }
 
+    //if the packet is a probe we need to analyze it
+    if(messageHandler_IsAProbe(message_FixedHeader(message))){
+      FibEntry *fibEntry = fib_MatchMessage(processor->fib, message);
+      if(fibEntry &&
+          fibEntry_GetFwdStrategyType(fibEntry) == SET_STRATEGY_LOW_LATENCY){
+        unsigned connid = message_GetIngressConnectionId(message);
+        NumberSet *outFace = numberSet_Create();
+        numberSet_Add(outFace, connid);
+        fibEntry_ReceiveObjectMessage(fibEntry, outFace, message, 0,
+                                      forwarder_GetTicks(processor->forwarder));
+        numberSet_Release(&(outFace));
+      }
+    }
+
     // we store the packets in the content store enven in the case where there
     // is no match in the PIT table in this way the applications can push the
     // content in the CS of the forwarder. We allow this only for local faces
diff --git a/hicn-light/src/hicn/processor/pitStandard.c b/hicn-light/src/hicn/processor/pitStandard.c
index edf0b5e98..d4961cdba 100644
--- a/hicn-light/src/hicn/processor/pitStandard.c
+++ b/hicn-light/src/hicn/processor/pitStandard.c
@@ -159,7 +159,6 @@ static PITVerdict _pitStandard_ReceiveInterest(PIT *generic,
                      ") and reverse path, forwarding",
                      (void *)interestMessage, pitEntry_GetExpiryTime(pitEntry));
         }
-
 #ifdef WITH_POLICY
         return PITVerdict_Retransmit;
 #else
@@ -215,12 +214,10 @@ static NumberSet *_pitStandard_SatisfyInterest(PIT *generic,
       // PIT entry is not expired, use it
       FibEntry *fibEntry = pitEntry_GetFibEntry(pitEntry);
       if (fibEntry != NULL) {
-        // this is a rough estimation of the residual RTT
-        Ticks rtt = forwarder_GetTicks(pit->forwarder) -
-                    pitEntry_GetCreationTime(pitEntry);
         fibEntry_ReceiveObjectMessage(fibEntry, pitEntry_GetEgressSet(pitEntry),
                                       objectMessage,
-                                      rtt);  // need to implement RTT
+                                      forwarder_GetTicks(pit->forwarder),
+                                      pitEntry_GetCreationTime(pitEntry));
       }
       const NumberSet *is = pitEntry_GetIngressSet(pitEntry);
       numberSet_AddSet(ingressSet, is);  // with this we do a copy so we can