DAS/node.py

@@ -3,6 +3,8 @@
 import random
 import collections
 import logging
+from collections import defaultdict
+import threading
 from DAS.block import *
 from DAS.tools import shuffled, shuffledDict, unionOfSamples
 from bitarray.util import zeros
@@ -76,6 +78,7 @@ class Node:
         self.repairedSampleCount = 0
         self.logger = logger
         self.validators = validators
+        self.received_gossip = defaultdict(list)
 
         if amIproposer:
             self.nodeClass = 0
@@ -246,14 +249,6 @@ class Node:
             self.statsRxDupInSlot += 1
         self.statsRxInSlot += 1
 
-    def receiveSegmentViaGossip(self, rID, cID, source):
-        """Receive a segment via gossipsub protocol from a specific source."""
-        if not self.amImalicious:
-            self.logger.trace("Recv via gossipsub %d-> %d: %d,%d", source, self.ID, rID, cID, extra=self.format)
-            self.receivedBlock.setSegment(rID, cID)
-            self.sampleRecvCount += 1
-        self.statsRxInSlot += 1
-
     def addToSendQueue(self, rID, cID):
         """Queue a segment for forwarding."""
         if self.perNodeQueue and not self.amImalicious:
@@ -512,40 +507,75 @@ class Node:
             if self.statsTxInSlot >= self.bwUplink:
                 return
 
-    def gossipSub(self, rows, cols):
+    def sendGossip(self, neigh):
-        """ This function facilitates the Gossipsub protocol for segment distribution among nodes.
+        """Simulate sending row and column IDs to a peer."""
-        It ensures that each node receives any missing segments by checking other nodes in the network.
+        have_info = {'source': self.ID, 'rowIDs': self.rowIDs, 'columnIDs': self.columnIDs}
+        neigh.node.received_gossip[self.ID].append(have_info)
+        neigh.node.msgRecvCount += 1
+        self.logger.debug(f"Gossip sent to {neigh.node.ID}: {neigh.node.received_gossip}", extra=self.format)
 
-        Args:
+    def process_received_gossip(self, simulator):
-            rows (dict): A hash table where the keys are row IDs and the values are lists of nodes that contain these rows.
-            cols (dict): A hash table where the keys are column IDs and the values are lists of nodes that contain these columns.
-        
-        Description:
-            - The function iterates through all row IDs and column IDs.
-            - For each segment identified by a row ID (rID) and a column ID (cID):
-                - It checks if the current node (self) already has the segment.
-                - If the segment is missing, it attempts to receive the segment from other nodes using the Gossipsub protocol via the receiveSegmentViaGossip method.
         """
-        for rID, rSources in rows.items():
+        Processes received gossip messages to request and receive data segments.
-            for cID, cSources in cols.items():
+        For each segment not already received, it simulates requesting the segment,
-                if not self.receivedBlock.getSegment(rID, cID):
+        logs the request and receipt, and updates the segment status and relevant counters.
-                    sources = list(set(rSources).intersection(cSources))
+        """
-                    if sources:
+        for sender, have_infos in self.received_gossip.items():
-                        source = sources[0]  # Pick the first source from the intersection
+            for have_info in have_infos:
-                        self.receiveSegmentViaGossip(rID, cID, source)
+                for rowID in have_info['rowIDs']:
-                        self.statsTxInSlot += 1  # request sent to receive segment via gossip
+                    for columnID in have_info['columnIDs']:
+                        if not self.receivedBlock.getSegment(rowID, columnID):
+                            # request for the segment
+                            self.logger.debug(f"Requesting segment ({rowID}, {columnID}) from {have_info['source']}", extra=self.format)
+                            self.msgSentCount += 1
+                            # source sends the segment
+                            self.logger.debug(f"Sending segment ({rowID}, {columnID}) to {self.ID} from {have_info['source']}", extra=self.format)
+                            simulator.validators[have_info['source']].sampleSentCount += 1
+                            simulator.validators[have_info['source']].statsTxInSlot += 1
+                            # receive the segment
+                            self.receivedBlock.setSegment(rowID, columnID)
+                            self.sampleRecvCount += 1
+                            self.logger.debug(f"Received segment ({rowID}, {columnID}) via gossip from {have_info['source']}", extra=self.format)
+        self.received_gossip.clear()
 
+    def gossip(self, simulator):
+        """
+        Periodically sends gossip messages to a random subset of neighbors to share information 
+        about data segments (row and column IDs). The process involves:
+        1. Selecting a random subset of row and column neighbors.
+        2. Sending the node's current state (row and column IDs) to these neighbors.
+        3. Neighbors process the received gossip and update their state accordingly.
         
-    def send(self, gossipsub, rows, cols):
+        This ensures data dissemination across the network with minimal delay, 
-        """ Send as much as we can in the timestep, limited by bwUplink."""
+        occurring at intervals defined by the HEARTBEAT timer.
-
+        """
-        if gossipsub:
+        if self.rowIDs:
-            if not self.amImalicious:
+            rID = random.choice(list(self.rowIDs))
-                self.gossipSub(rows, cols)
+            rowNeighs = list(self.rowNeighbors[rID].values())
+            num_row_peers = random.randint(1, len(rowNeighs))
+            selected_row_neighs = random.sample(rowNeighs, num_row_peers)
+            for rowNeigh in selected_row_neighs:
+                self.sendGossip(rowNeigh)
+                self.msgSentCount += 1
+                rowNeigh.node.process_received_gossip(simulator)
                 if self.statsTxInSlot >= self.bwUplink:
                     return
 
-        else:
+        if self.columnIDs:
+            cID = random.choice(list(self.columnIDs))
+            columnNeighs = list(self.columnNeighbors[cID].values())
+            num_column_peers = random.randint(1, len(columnNeighs))
+            selected_column_neighs = random.sample(columnNeighs, num_column_peers)
+            for columnNeigh in selected_column_neighs:
+                self.sendGossip(columnNeigh)
+                self.msgSentCount += 1
+                columnNeigh.node.process_received_gossip(simulator)
+                if self.statsTxInSlot >= self.bwUplink:
+                    return
+
+    def send(self):
+        """ Send as much as we can in the timestep, limited by bwUplink."""
+
         # process node level send queue
         if not self.amImalicious:
             self.processSendQueue()

DAS/simulator.py

@@ -278,22 +278,16 @@ class Simulator:
             self.logger.debug("Expected Samples: %d" % expected, extra=self.format)
             self.logger.debug("Missing Samples: %d" % missingSamples, extra=self.format)
             oldMissingSamples = missingSamples
-            rows = {}
+
-            cols = {}
-            for i in range(0, self.shape.numberNodes):
-                if not self.validators[i].amIproposer and not self.validators[i].amImalicious:
-                    for id in self.validators[i].columnIDs:
-                        if id not in cols:
-                            cols[id] = []
-                        cols[id].append(self.validators[i])
-                    for id in self.validators[i].rowIDs:
-                        if id not in rows:
-                            rows[id] = []
-                        rows[id].append(self.validators[i])
             self.logger.debug("PHASE SEND %d" % steps, extra=self.format)
             for i in range(0,self.shape.numberNodes):
                 if not self.validators[i].amImalicious:
-                    self.validators[i].send(self.config.gossipsub, rows, cols)
+                    self.validators[i].send()
+            if steps % self.config.heartbeat == 0 and self.config.gossip:
+                self.logger.debug("PHASE GOSSIP %d" % steps, extra=self.format)
+                for i in range(1,self.shape.numberNodes):
+                    if not self.validators[i].amImalicious:
+                        self.validators[i].gossip(self)
             self.logger.debug("PHASE RECEIVE %d" % steps, extra=self.format)
             for i in range(1,self.shape.numberNodes):
                 self.validators[i].receiveRowsColumns()

smallConf.py

@@ -60,7 +60,10 @@ maliciousNodes = range(40,41,20)
 randomizeMaliciousNodes = True
 
 # When set to True, nodes will use the Gossipsub protocol for communication
-gossipsub = False
+gossip = True
+
+# Heartbeat interval for gossip messages in simulation steps
+heartbeat = 10
 
 # Per-topic mesh neighborhood size
 netDegrees = range(8, 9, 2)