class BGPDecisionProcess:
    def __init__(self):
        self.route_table = {}
        self.policy_engine = PolicyEngine()
        self.path_attributes = PathAttributeProcessor()
        
    def best_path_selection(self, routes):
        """Implement BGP best path selection algorithm"""
        if not routes:
            return None
            
        # Step 1: Prefer highest Weight (Cisco proprietary)
        routes = self.filter_by_weight(routes)
        if len(routes) == 1:
            return routes[0]
            
        # Step 2: Prefer highest Local Preference
        routes = self.filter_by_local_preference(routes)
        if len(routes) == 1:
            return routes[0]
            
        # Step 3: Prefer locally originated routes
        routes = self.filter_by_origin(routes)
        if len(routes) == 1:
            return routes[0]
            
        # Step 4: Prefer shortest AS Path
        routes = self.filter_by_as_path_length(routes)
        if len(routes) == 1:
            return routes[0]
            
        # Step 5: Prefer lowest Origin code (IGP < EGP < Incomplete)
        routes = self.filter_by_origin_code(routes)
        if len(routes) == 1:
            return routes[0]
            
        # Step 6: Prefer lowest MED (when from same AS)
        routes = self.filter_by_med(routes)
        if len(routes) == 1:
            return routes[0]
            
        # Step 7: Prefer eBGP over iBGP
        routes = self.filter_by_path_type(routes)
        if len(routes) == 1:
            return routes[0]
            
        # Step 8: Prefer path with lowest IGP metric to BGP next hop
        routes = self.filter_by_igp_metric(routes)
        if len(routes) == 1:
            return routes[0]
            
        # Step 9: Prefer oldest route (for stability)
        routes = self.filter_by_age(routes)
        if len(routes) == 1:
            return routes[0]
            
        # Step 10: Prefer lowest Router ID
        return self.filter_by_router_id(routes)[0]
    
    def filter_by_local_preference(self, routes):
        """Filter routes by highest local preference"""
        max_local_pref = max(route.local_preference for route in routes)
        return [route for route in routes 
                if route.local_preference == max_local_pref]
    
    def filter_by_as_path_length(self, routes):
        """Filter routes by shortest AS path length"""
        min_path_length = min(len(route.as_path) for route in routes)
        return [route for route in routes 
                if len(route.as_path) == min_path_length]
    
    def apply_inbound_policy(self, route, neighbor):
        """Apply inbound routing policy"""
        # Route filtering
        if self.policy_engine.should_filter_route(route, neighbor):
            return None
            
        # Attribute modification
        route = self.policy_engine.modify_attributes(route, neighbor)
        
        # Local preference assignment
        route.local_preference = self.policy_engine.calculate_local_preference(
            route, neighbor
        )
        
        return route
    
    def apply_outbound_policy(self, route, neighbor):
        """Apply outbound routing policy"""
        # AS path prepending for traffic engineering
        route.as_path = self.policy_engine.apply_as_path_prepending(
            route, neighbor
        )
        
        # MED modification
        route.med = self.policy_engine.calculate_med(route, neighbor)
        
        # Community tagging
        route.communities = self.policy_engine.add_communities(
            route, neighbor
        )
        
        return route

package bgp

import (
    "net"
    "sync"
    "time"
)

type RouteReflector struct {
    RouterID        net.IP
    ClusterID       uint32
    Clients         map[string]*BGPPeer
    NonClients      map[string]*BGPPeer
    RIB             *RoutingInformationBase
    PolicyEngine    *PolicyEngine
    mutex           sync.RWMutex
}

type BGPPeer struct {
    Address         net.IP
    ASN             uint32
    State           PeerState
    Capabilities    []Capability
    AdjRIBIn        *RIB
    AdjRIBOut       *RIB
    LocalRIB        *RIB
    LastKeepalive   time.Time
    IsClient        bool
    IsConfederation bool
}

func (rr *RouteReflector) ProcessUpdate(update *BGPUpdate, 
                                       fromPeer *BGPPeer) {
    rr.mutex.Lock()
    defer rr.mutex.Unlock()
    
    // Store in Adj-RIB-In
    fromPeer.AdjRIBIn.AddRoute(update.Route)
    
    // Apply import policies
    processedRoute := rr.PolicyEngine.ApplyImportPolicy(
        update.Route, fromPeer
    )
    
    if processedRoute == nil {
        return // Route filtered
    }
    
    // Store in Loc-RIB
    rr.RIB.AddRoute(processedRoute)
    
    // Run best path selection
    bestPath := rr.RIB.SelectBestPath(processedRoute.Prefix)
    
    // Advertise to peers based on route reflection rules
    rr.advertiseToEligiblePeers(bestPath, fromPeer)
}

func (rr *RouteReflector) advertiseToEligiblePeers(route *BGPRoute, 
                                                  fromPeer *BGPPeer) {
    for _, peer := range rr.getAllPeers() {
        if peer == fromPeer {
            continue // Don't advertise back to originator
        }
        
        if rr.shouldAdvertiseToPeer(route, fromPeer, peer) {
            advertisedRoute := rr.prepareAdvertisement(route, peer)
            peer.AdjRIBOut.AddRoute(advertisedRoute)
            rr.sendUpdate(peer, advertisedRoute)
        }
    }
}

func (rr *RouteReflector) shouldAdvertiseToPeer(route *BGPRoute,
                                               fromPeer, toPeer *BGPPeer) bool {
    // Route reflection rules
    if fromPeer.IsClient && toPeer.IsClient {
        // Client to client reflection allowed
        return true
    }
    
    if fromPeer.IsClient && !toPeer.IsClient {
        // Client to non-client reflection allowed
        return true
    }
    
    if !fromPeer.IsClient && toPeer.IsClient {
        // Non-client to client reflection allowed
        return true
    }
    
    // Non-client to non-client reflection not allowed
    return false
}

func (rr *RouteReflector) prepareAdvertisement(route *BGPRoute,
                                              toPeer *BGPPeer) *BGPRoute {
    advertisedRoute := route.Copy()
    
    // Add originator ID if not present
    if advertisedRoute.OriginatorID == nil {
        advertisedRoute.OriginatorID = &rr.RouterID
    }
    
    // Add cluster ID to cluster list
    advertisedRoute.ClusterList = append(
        advertisedRoute.ClusterList, 
        rr.ClusterID
    )
    
    // Apply export policies
    advertisedRoute = rr.PolicyEngine.ApplyExportPolicy(
        advertisedRoute, toPeer
    )
    
    return advertisedRoute
}

class MultiHomingController:
    def __init__(self):
        self.providers = {}
        self.traffic_analyzer = TrafficAnalyzer()
        self.latency_monitor = LatencyMonitor()
        self.cost_calculator = CostCalculator()
        
    def add_provider(self, provider_config):
        """Add ISP provider configuration"""
        provider = ISPProvider(
            asn=provider_config['asn'],
            prefixes=provider_config['prefixes'],
            cost_model=provider_config['cost_model'],
            sla_metrics=provider_config['sla'],
            primary_link=provider_config['primary_link'],
            backup_links=provider_config.get('backup_links', [])
        )
        
        self.providers[provider.asn] = provider
        
    def optimize_traffic_distribution(self):
        """Optimize traffic distribution across providers"""
        current_traffic = self.traffic_analyzer.get_current_flows()
        
        for destination in current_traffic:
            optimal_path = self.calculate_optimal_path(
                destination, 
                current_traffic[destination]
            )
            
            if optimal_path != destination.current_path:
                self.implement_traffic_engineering(destination, optimal_path)
    
    def calculate_optimal_path(self, destination, traffic_profile):
        """Calculate optimal path based on multiple criteria"""
        candidates = []
        
        for provider_asn, provider in self.providers.items():
            if destination.prefix in provider.reachable_prefixes:
                score = self.calculate_path_score(
                    provider, 
                    destination, 
                    traffic_profile
                )
                candidates.append((provider, score))
        
        # Sort by score (higher is better)
        candidates.sort(key=lambda x: x[1], reverse=True)
        
        return candidates[0][0] if candidates else None
    
    def calculate_path_score(self, provider, destination, traffic_profile):
        """Calculate path score based on weighted criteria"""
        weights = {
            'latency': 0.3,
            'cost': 0.25,
            'reliability': 0.25,
            'bandwidth': 0.2
        }
        
        # Latency score (lower is better, so invert)
        latency = self.latency_monitor.get_latency(provider, destination)
        latency_score = max(0, 100 - latency)
        
        # Cost score (lower is better, so invert)
        cost = self.cost_calculator.calculate_cost(
            provider, 
            traffic_profile
        )
        cost_score = max(0, 100 - (cost / 10))  # Normalize
        
        # Reliability score
        reliability_score = provider.sla_metrics.availability * 100
        
        # Bandwidth score
        utilization = traffic_profile.bandwidth / provider.bandwidth_limit
        bandwidth_score = max(0, 100 - (utilization * 100))
        
        total_score = (
            weights['latency'] * latency_score +
            weights['cost'] * cost_score +
            weights['reliability'] * reliability_score +
            weights['bandwidth'] * bandwidth_score
        )
        
        return total_score

# Cisco IOS XR configuration for advanced BGP communities
router bgp 65001
 address-family ipv4 unicast
  !
  ! Define community sets for traffic engineering
  community-set PREFER_PROVIDER_A
   65001:100
  end-set
  !
  community-set BACKUP_PATH
   65001:200
  end-set
  !
  community-set NO_EXPORT_TO_PEER
   65001:666
  end-set
  !
  community-set PREPEND_ONCE
   65001:1000
  end-set
  !
  community-set PREPEND_TWICE
   65001:2000
  end-set
  !
  community-set PREPEND_THRICE
   65001:3000
  end-set
  !
 address-family ipv6 unicast
 !
 neighbor-group PROVIDER_A_GROUP
  remote-as 1299
  address-family ipv4 unicast
   route-policy PROVIDER_A_IN in
   route-policy PROVIDER_A_OUT out
   maximum-prefix 800000 85
   send-community-ebgp
  !
  address-family ipv6 unicast
   route-policy PROVIDER_A_IN_V6 in
   route-policy PROVIDER_A_OUT_V6 out
   maximum-prefix 150000 85
   send-community-ebgp
  !
 !
 neighbor-group PROVIDER_B_GROUP
  remote-as 174
  address-family ipv4 unicast
   route-policy PROVIDER_B_IN in
   route-policy PROVIDER_B_OUT out
   maximum-prefix 800000 85
   send-community-ebgp
  !
 !
 neighbor 203.0.113.1
  use neighbor-group PROVIDER_A_GROUP
  description "Provider A Primary Link"
 !
 neighbor 203.0.113.5
  use neighbor-group PROVIDER_B_GROUP
  description "Provider B Primary Link"
 !

# Traffic engineering policies
route-policy PROVIDER_A_OUT
  if destination in PREFIX_SET_CUSTOMER_ROUTES then
    if community matches-any PREPEND_ONCE then
      prepend as-path 65001 1
    elseif community matches-any PREPEND_TWICE then
      prepend as-path 65001 2
    elseif community matches-any PREPEND_THRICE then
      prepend as-path 65001 3
    endif
    set med 100
    set community (65001:100) additive
  endif
  pass
end-policy

route-policy PROVIDER_B_OUT
  if destination in PREFIX_SET_CUSTOMER_ROUTES then
    if community matches-any PREFER_PROVIDER_A then
      prepend as-path 65001 2
      set med 200
    else
      set med 150
    endif
    set community (65001:200) additive
  endif
  pass
end-policy

route-policy PROVIDER_A_IN
  if as-path in AS_PATH_SET_KNOWN_PROVIDERS then
    set local-preference 200
  else
    set local-preference 100
  endif
  if community matches-any NO_EXPORT_TO_PEER then
    set community no-export additive
  endif
  pass
end-policy

class RPKIValidator:
    def __init__(self):
        self.roa_cache = {}
        self.rtr_sessions = []
        self.validation_stats = ValidationStats()
        
    def validate_route_origin(self, prefix, origin_asn, route_source):
        """Validate route origin against RPKI ROAs"""
        validation_result = self.lookup_roa(prefix, origin_asn)
        
        self.validation_stats.update(validation_result)
        
        return validation_result
    
    def lookup_roa(self, prefix, origin_asn):
        """Look up Route Origin Authorization"""
        # Check exact match
        roa_key = f"{prefix}#{origin_asn}"
        if roa_key in self.roa_cache:
            roa = self.roa_cache[roa_key]
            if self.is_roa_valid(roa):
                return ValidationResult.VALID
        
        # Check covering ROAs
        covering_roas = self.find_covering_roas(prefix)
        for roa in covering_roas:
            if (roa.origin_asn == origin_asn and 
                self.prefix_within_max_length(prefix, roa)):
                return ValidationResult.VALID
        
        # Check for conflicting ROAs
        conflicting_roas = self.find_conflicting_roas(prefix, origin_asn)
        if conflicting_roas:
            return ValidationResult.INVALID
        
        # No ROA found
        return ValidationResult.NOT_FOUND
    
    def is_roa_valid(self, roa):
        """Check if ROA is still valid"""
        return (roa.not_before <= time.time() <= roa.not_after and
                not roa.revoked)
    
    def update_roa_cache(self, rtr_response):
        """Update ROA cache from RTR response"""
        for roa in rtr_response.roas:
            if roa.flags.announcement:
                # Add ROA
                roa_key = f"{roa.prefix}#{roa.origin_asn}"
                self.roa_cache[roa_key] = roa
            else:
                # Withdraw ROA
                roa_key = f"{roa.prefix}#{roa.origin_asn}"
                if roa_key in self.roa_cache:
                    del self.roa_cache[roa_key]

class BGPSecurityFilter:
    def __init__(self):
        self.rpki_validator = RPKIValidator()
        self.bogon_filter = BogonFilter()
        self.irr_validator = IRRValidator()
        
    def validate_incoming_route(self, route, peer):
        """Comprehensive route validation"""
        validations = []
        
        # RPKI validation
        rpki_result = self.rpki_validator.validate_route_origin(
            route.prefix, 
            route.origin_asn, 
            peer
        )
        validations.append(('RPKI', rpki_result))
        
        # Bogon filtering
        if self.bogon_filter.is_bogon_prefix(route.prefix):
            validations.append(('BOGON', ValidationResult.INVALID))
        else:
            validations.append(('BOGON', ValidationResult.VALID))
        
        # AS path validation
        as_path_result = self.validate_as_path(route.as_path)
        validations.append(('AS_PATH', as_path_result))
        
        # IRR validation
        irr_result = self.irr_validator.validate_route(route, peer)
        validations.append(('IRR', irr_result))
        
        # Prefix length validation
        length_result = self.validate_prefix_length(route.prefix)
        validations.append(('PREFIX_LENGTH', length_result))
        
        return self.calculate_overall_validity(validations)
    
    def validate_as_path(self, as_path):
        """Validate AS path for common attacks"""
        # Check for private ASNs in path
        private_asns = [asn for asn in as_path 
                       if 64512 <= asn <= 65535 or 4200000000 <= asn <= 4294967295]
        if private_asns:
            return ValidationResult.INVALID
        
        # Check for bogon ASNs
        bogon_asns = [asn for asn in as_path if asn in self.bogon_asns]
        if bogon_asns:
            return ValidationResult.INVALID
        
        # Check for suspicious AS path length
        if len(as_path) > 25:  # Unusually long path
            return ValidationResult.SUSPICIOUS
        
        # Check for AS path loops
        if len(as_path) != len(set(as_path)):
            return ValidationResult.INVALID
        
        return ValidationResult.VALID

package bgpmon

import (
    "context"
    "encoding/json"
    "time"
    "sync"
)

type BGPMonitor struct {
    collectors      map[string]*RouteCollector
    analyzer        *RouteAnalyzer
    alertManager    *AlertManager
    metricsStore    *MetricsStore
    eventProcessor  *EventProcessor
    ctx             context.Context
    cancel          context.CancelFunc
    mutex           sync.RWMutex
}

type RouteEvent struct {
    Timestamp    time.Time    `json:"timestamp"`
    Type         EventType    `json:"type"`
    Prefix       string       `json:"prefix"`
    AsPath       []uint32     `json:"as_path"`
    NextHop      string       `json:"next_hop"`
    Origin       uint32       `json:"origin"`
    Collector    string       `json:"collector"`
    Peer         string       `json:"peer"`
    Attributes   []Attribute  `json:"attributes"`
}

func NewBGPMonitor() *BGPMonitor {
    ctx, cancel := context.WithCancel(context.Background())
    
    return &BGPMonitor{
        collectors:     make(map[string]*RouteCollector),
        analyzer:       NewRouteAnalyzer(),
        alertManager:   NewAlertManager(),
        metricsStore:   NewMetricsStore(),
        eventProcessor: NewEventProcessor(),
        ctx:            ctx,
        cancel:         cancel,
    }
}

func (bm *BGPMonitor) AddCollector(name string, config CollectorConfig) error {
    bm.mutex.Lock()
    defer bm.mutex.Unlock()
    
    collector, err := NewRouteCollector(config)
    if err != nil {
        return err
    }
    
    bm.collectors[name] = collector
    
    // Start collector goroutine
    go bm.runCollector(name, collector)
    
    return nil
}

func (bm *BGPMonitor) runCollector(name string, collector *RouteCollector) {
    eventChan := collector.Start(bm.ctx)
    
    for {
        select {
        case event := <-eventChan:
            bm.processRouteEvent(event, name)
        case <-bm.ctx.Done():
            return
        }
    }
}

func (bm *BGPMonitor) processRouteEvent(event *RouteEvent, 
                                       collectorName string) {
    event.Collector = collectorName
    
    // Store raw event
    bm.metricsStore.StoreEvent(event)
    
    // Analyze event
    analysis := bm.analyzer.AnalyzeEvent(event)
    
    // Check for anomalies
    anomalies := bm.detectAnomalies(event, analysis)
    
    // Generate alerts if necessary
    for _, anomaly := range anomalies {
        alert := bm.generateAlert(anomaly, event)
        bm.alertManager.SendAlert(alert)
    }
    
    // Update metrics
    bm.updateMetrics(event, analysis)
}

func (bm *BGPMonitor) detectAnomalies(event *RouteEvent, 
                                     analysis *RouteAnalysis) []*Anomaly {
    var anomalies []*Anomaly
    
    // Detect prefix hijacking
    if analysis.PossibleHijack {
        anomalies = append(anomalies, &Anomaly{
            Type:        "PREFIX_HIJACK",
            Severity:    "HIGH",
            Description: "Possible prefix hijacking detected",
            Prefix:      event.Prefix,
            SuspiciousASN: event.Origin,
        })
    }
    
    // Detect route leaks
    if analysis.PossibleLeak {
        anomalies = append(anomalies, &Anomaly{
            Type:        "ROUTE_LEAK",
            Severity:    "MEDIUM",
            Description: "Possible route leak detected",
            Prefix:      event.Prefix,
            LeakingASN:  analysis.LeakingASN,
        })
    }
    
    // Detect unusual AS path lengths
    if len(event.AsPath) > 20 {
        anomalies = append(anomalies, &Anomaly{
            Type:        "LONG_AS_PATH",
            Severity:    "LOW",
            Description: "Unusually long AS path detected",
            Prefix:      event.Prefix,
            PathLength:  len(event.AsPath),
        })
    }
    
    return anomalies
}

type RouteAnalyzer struct {
    historicalData  *HistoricalRouteDB
    asRelationships *ASRelationshipDB
    rpkiValidator   *RPKIValidator
    geoIPDB         *GeoIPDatabase
}

func (ra *RouteAnalyzer) AnalyzeEvent(event *RouteEvent) *RouteAnalysis {
    analysis := &RouteAnalysis{
        Event: event,
    }
    
    // Analyze origin history
    historical := ra.historicalData.GetPrefixHistory(event.Prefix)
    analysis.OriginHistory = historical
    
    if len(historical) > 0 {
        // Check if origin ASN has changed
        lastOrigin := historical[len(historical)-1].Origin
        if lastOrigin != event.Origin {
            analysis.OriginChanged = true
            analysis.PreviousOrigin = lastOrigin
            
            // Check if new origin is suspicious
            if !ra.isLegitimateOriginChange(event.Prefix, 
                                          lastOrigin, 
                                          event.Origin) {
                analysis.PossibleHijack = true
            }
        }
    }
    
    // Analyze AS path
    analysis.PathAnalysis = ra.analyzeASPath(event.AsPath)
    
    // Geographic analysis
    analysis.GeoAnalysis = ra.analyzeGeography(event)
    
    // RPKI validation
    rpkiResult := ra.rpkiValidator.validate_route_origin(
        event.Prefix, 
        event.Origin, 
        event.Peer
    )
    analysis.RPKIStatus = rpkiResult
    
    return analysis
}

class BGPPerformanceAnalyzer:
    def __init__(self):
        self.convergence_monitor = ConvergenceMonitor()
        self.path_diversity_analyzer = PathDiversityAnalyzer()
        self.churn_detector = ChurnDetector()
        
    def analyze_convergence_time(self, failure_event):
        """Analyze BGP convergence time after network events"""
        start_time = failure_event.timestamp
        
        # Monitor route updates following the event
        convergence_data = self.convergence_monitor.track_convergence(
            start_time=start_time,
            affected_prefixes=failure_event.affected_prefixes,
            monitoring_duration=300  # 5 minutes
        )
        
        results = {
            'total_convergence_time': convergence_data.total_time,
            'per_prefix_convergence': {},
            'update_count': convergence_data.update_count,
            'churn_detected': False
        }
        
        for prefix in failure_event.affected_prefixes:
            prefix_convergence = convergence_data.get_prefix_convergence(prefix)
            results['per_prefix_convergence'][prefix] = {
                'convergence_time': prefix_convergence.time,
                'path_changes': prefix_convergence.path_changes,
                'final_path': prefix_convergence.final_path
            }
            
            # Detect route flapping
            if prefix_convergence.path_changes > 10:
                results['churn_detected'] = True
        
        return results
    
    def analyze_path_diversity(self, destination_prefixes):
        """Analyze path diversity for critical destinations"""
        diversity_report = {}
        
        for prefix in destination_prefixes:
            paths = self.get_available_paths(prefix)
            
            diversity_metrics = {
                'total_paths': len(paths),
                'unique_next_hops': len(set(path.next_hop for path in paths)),
                'as_path_diversity': self.calculate_as_path_diversity(paths),
                'geographic_diversity': self.calculate_geo_diversity(paths),
                'provider_diversity': self.calculate_provider_diversity(paths)
            }
            
            # Calculate diversity score (0-100)
            diversity_score = self.calculate_diversity_score(diversity_metrics)
            diversity_metrics['diversity_score'] = diversity_score
            
            diversity_report[prefix] = diversity_metrics
        
        return diversity_report
    
    def calculate_as_path_diversity(self, paths):
        """Calculate AS path diversity using Shannon entropy"""
        if not paths:
            return 0
        
        # Count unique AS paths
        path_counts = {}
        for path in paths:
            path_str = ','.join(map(str, path.as_path))
            path_counts[path_str] = path_counts.get(path_str, 0) + 1
        
        # Calculate Shannon entropy
        total_paths = len(paths)
        entropy = 0
        for count in path_counts.values():
            probability = count / total_paths
            if probability > 0:
                entropy -= probability * math.log2(probability)
        
        # Normalize to 0-1 range
        max_entropy = math.log2(len(path_counts)) if len(path_counts) > 1 else 1
        normalized_entropy = entropy / max_entropy if max_entropy > 0 else 0
        
        return normalized_entropy

class MLTrafficEngineer:
    def __init__(self):
        self.predictor = TrafficPredictor()
        self.optimizer = PathOptimizer()
        self.policy_generator = PolicyGenerator()
        self.feedback_loop = FeedbackLoop()
        
    def optimize_traffic_flows(self, network_state):
        """Optimize traffic flows using ML predictions"""
        # Predict future traffic patterns
        traffic_forecast = self.predictor.predict_traffic(
            current_state=network_state,
            forecast_horizon=3600  # 1 hour
        )
        
        # Analyze current path performance
        path_performance = self.analyze_path_performance(network_state)
        
        # Generate optimization recommendations
        optimizations = self.optimizer.generate_optimizations(
            traffic_forecast=traffic_forecast,
            path_performance=path_performance,
            constraints=network_state.constraints
        )
        
        # Convert to BGP policies
        bgp_policies = self.policy_generator.generate_policies(optimizations)
        
        return bgp_policies
    
    def analyze_path_performance(self, network_state):
        """Analyze performance of current paths"""
        performance_metrics = {}
        
        for destination in network_state.destinations:
            current_path = network_state.get_active_path(destination)
            
            metrics = {
                'latency': self.measure_latency(current_path),
                'bandwidth_utilization': self.measure_utilization(current_path),
                'packet_loss': self.measure_packet_loss(current_path),
                'jitter': self.measure_jitter(current_path),
                'cost': self.calculate_cost(current_path)
            }
            
            # Calculate composite performance score
            performance_score = self.calculate_performance_score(metrics)
            metrics['performance_score'] = performance_score
            
            performance_metrics[destination] = metrics
        
        return performance_metrics
    
    def generate_te_policies(self, optimizations):
        """Generate traffic engineering policies"""
        policies = []
        
        for optimization in optimizations:
            if optimization.type == 'path_preference':
                policy = self.create_path_preference_policy(optimization)
            elif optimization.type == 'load_balancing':
                policy = self.create_load_balancing_policy(optimization)
            elif optimization.type == 'failover':
                policy = self.create_failover_policy(optimization)
            
            policies.append(policy)
        
        return policies
    
    def create_path_preference_policy(self, optimization):
        """Create BGP policy for path preference"""
        policy = BGPPolicy(
            name=f"prefer_path_{optimization.destination}",
            type="route_map"
        )
        
        # Set local preference for preferred path
        policy.add_rule(
            match_conditions=[
                MatchPrefix(optimization.destination),
                MatchASPath(optimization.preferred_path.as_path)
            ],
            actions=[
                SetLocalPreference(optimization.local_preference)
            ]
        )
        
        # Add prepending for less preferred paths
        for alt_path in optimization.alternative_paths:
            prepend_count = optimization.get_prepend_count(alt_path)
            if prepend_count > 0:
                policy.add_rule(
                    match_conditions=[
                        MatchPrefix(optimization.destination),
                        MatchASPath(alt_path.as_path)
                    ],
                    actions=[
                        PrependASPath(count=prepend_count)
                    ]
                )
        
        return policy

package cloudgw

import (
    "context"
    "net"
    "sync"
)

type CloudBGPGateway struct {
    LocalASN        uint32
    RouterID        net.IP
    CloudProviders  map[string]*CloudProvider
    OnPremPeers     map[string]*BGPPeer
    RouteTable      *CloudRouteTable
    PolicyEngine    *CloudPolicyEngine
    mutex           sync.RWMutex
}

type CloudProvider struct {
    Name            string
    ASN             uint32
    VirtualGateways []*VirtualGateway
    PeerConnections []*BGPPeer
    RouteFilters    []*RouteFilter
    CostModel       *CostModel
}

type VirtualGateway struct {
    ID              string
    Provider        string
    RemoteASN       uint32
    LocalAddress    net.IP
    RemoteAddress   net.IP
    BGPSession      *BGPSession
    TunnelConfig    *TunnelConfig
}

func (cgw *CloudBGPGateway) EstablishCloudConnectivity(
    provider string, 
    config *CloudConnectivityConfig) error {
    
    cgw.mutex.Lock()
    defer cgw.mutex.Unlock()
    
    // Create virtual gateway
    vgw := &VirtualGateway{
        ID:            config.GatewayID,
        Provider:      provider,
        RemoteASN:     config.RemoteASN,
        LocalAddress:  config.LocalAddress,
        RemoteAddress: config.RemoteAddress,
    }
    
    // Establish BGP session
    session, err := cgw.establishBGPSession(vgw, config)
    if err != nil {
        return err
    }
    vgw.BGPSession = session
    
    // Configure route filtering
    filters := cgw.createCloudRouteFilters(provider, config)
    
    // Add to cloud provider
    if cgw.CloudProviders[provider] == nil {
        cgw.CloudProviders[provider] = &CloudProvider{
            Name: provider,
            ASN:  config.RemoteASN,
        }
    }
    
    cgw.CloudProviders[provider].VirtualGateways = append(
        cgw.CloudProviders[provider].VirtualGateways,
        vgw
    )
    
    return nil
}

func (cgw *CloudBGPGateway) OptimizeCloudRouting() {
    """Optimize routing across cloud and on-premise resources"""
    
    // Analyze current traffic patterns
    trafficAnalysis := cgw.analyzeTrafficPatterns()
    
    // Calculate optimal routing policies
    optimizations := cgw.calculateOptimalRouting(trafficAnalysis)
    
    // Apply optimizations
    for _, optimization := range optimizations {
        cgw.applyRoutingOptimization(optimization)
    }
}

func (cgw *CloudBGPGateway) calculateOptimalRouting(
    analysis *TrafficAnalysis) []*RoutingOptimization {
    
    var optimizations []*RoutingOptimization
    
    for destination, traffic := range analysis.DestinationTraffic {
        // Consider all available paths
        availablePaths := cgw.getAvailablePaths(destination)
        
        // Calculate costs for each path
        pathCosts := make(map[*BGPPath]float64)
        for _, path := range availablePaths {
            cost := cgw.calculatePathCost(path, traffic)
            pathCosts[path] = cost
        }
        
        // Find optimal path
        optimalPath := cgw.findOptimalPath(pathCosts)
        
        // Check if current path is optimal
        currentPath := cgw.RouteTable.GetActivePath(destination)
        if currentPath != optimalPath {
            optimization := &RoutingOptimization{
                Destination:    destination,
                CurrentPath:    currentPath,
                OptimalPath:    optimalPath,
                ExpectedSavings: pathCosts[currentPath] - pathCosts[optimalPath],
            }
            optimizations = append(optimizations, optimization)
        }
    }
    
    return optimizations
}

func (cgw *CloudBGPGateway) calculatePathCost(path *BGPPath, 
                                             traffic *TrafficProfile) float64 {
    var totalCost float64
    
    // Bandwidth cost
    for _, segment := range path.Segments {
        if segment.Provider != "" {
            provider := cgw.CloudProviders[segment.Provider]
            bandwidthCost := provider.CostModel.CalculateBandwidthCost(
                traffic.AverageBandwidth
            )
            totalCost += bandwidthCost
        }
    }
    
    // Latency penalty
    latencyPenalty := path.Latency * traffic.LatencySensitivity
    totalCost += latencyPenalty
    
    // Reliability factor
    reliabilityDiscount := path.Reliability * 0.1
    totalCost -= reliabilityDiscount
    
    return totalCost
}

class BGPAutomationFramework:
    def __init__(self):
        self.device_manager = DeviceManager()
        self.template_engine = TemplateEngine()
        self.validation_engine = ValidationEngine()
        self.rollback_manager = RollbackManager()
        self.change_tracker = ChangeTracker()
        
    def deploy_bgp_configuration(self, deployment_plan):
        """Deploy BGP configuration with full automation"""
        # Validate deployment plan
        validation_result = self.validation_engine.validate_plan(deployment_plan)
        if not validation_result.is_valid:
            raise ValidationError(validation_result.errors)
        
        # Create rollback point
        rollback_id = self.rollback_manager.create_checkpoint(
            deployment_plan.target_devices
        )
        
        try:
            # Execute deployment
            results = self.execute_deployment(deployment_plan)
            
            # Verify deployment
            verification_result = self.verify_deployment(
                deployment_plan, 
                results
            )
            
            if verification_result.success:
                self.change_tracker.record_successful_deployment(
                    deployment_plan, 
                    results
                )
                return results
            else:
                # Rollback on verification failure
                self.rollback_manager.rollback(rollback_id)
                raise DeploymentError("Deployment verification failed")
                
        except Exception as e:
            # Rollback on any error
            self.rollback_manager.rollback(rollback_id)
            raise
    
    def execute_deployment(self, plan):
        """Execute BGP deployment plan"""
        results = {}
        
        # Deploy in dependency order
        for stage in plan.deployment_stages:
            stage_results = self.execute_stage(stage)
            results[stage.name] = stage_results
            
            # Wait for BGP convergence
            if stage.wait_for_convergence:
                self.wait_for_convergence(stage.target_devices)
        
        return results
    
    def execute_stage(self, stage):
        """Execute a single deployment stage"""
        stage_results = {}
        
        # Parallel execution for independent devices
        with ThreadPoolExecutor(max_workers=stage.parallelism) as executor:
            futures = {}
            
            for device in stage.target_devices:
                future = executor.submit(
                    self.configure_device, 
                    device, 
                    stage.configuration
                )
                futures[device] = future
            
            # Collect results
            for device, future in futures.items():
                try:
                    result = future.result(timeout=stage.timeout)
                    stage_results[device] = result
                except Exception as e:
                    stage_results[device] = ConfigurationError(str(e))
        
        return stage_results
    
    def configure_device(self, device, configuration):
        """Configure individual device"""
        # Connect to device
        connection = self.device_manager.connect(device)
        
        try:
            # Generate device-specific configuration
            device_config = self.template_engine.render_config(
                template=configuration.template,
                variables=configuration.variables,
                device_type=device.device_type
            )
            
            # Validate configuration syntax
            validation = self.validation_engine.validate_config(
                device_config, 
                device.device_type
            )
            if not validation.is_valid:
                raise ConfigurationError(validation.errors)
            
            # Apply configuration
            result = connection.apply_configuration(
                device_config,
                commit=configuration.auto_commit
            )
            
            return result
            
        finally:
            connection.disconnect()