diff --git a/src/net.cpp b/src/net.cpp
index bc9d753c75a8b2..252d079c3a3876 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -145,11 +145,10 @@ static std::vector<CAddress> convertSeed6(const std::vector<SeedSpec6> &vSeedsIn
     const int64_t nOneWeek = 7*24*60*60;
     std::vector<CAddress> vSeedsOut;
     vSeedsOut.reserve(vSeedsIn.size());
-    for (std::vector<SeedSpec6>::const_iterator i(vSeedsIn.begin()); i != vSeedsIn.end(); ++i)
-    {
+    for (const auto& seed_in : vSeedsIn) {
         struct in6_addr ip;
-        memcpy(&ip, i->addr, sizeof(ip));
-        CAddress addr(CService(ip, i->port), NODE_NETWORK);
+        memcpy(&ip, seed_in.addr, sizeof(ip));
+        CAddress addr(CService(ip, seed_in.port), NODE_NETWORK);
         addr.nTime = GetTime() - GetRand(nOneWeek) - nOneWeek;
         vSeedsOut.push_back(addr);
     }
@@ -309,18 +308,22 @@ bool IsReachable(const CNetAddr& addr)
 CNode* CConnman::FindNode(const CNetAddr& ip)
 {
     LOCK(cs_vNodes);
-    for (CNode* pnode : vNodes)
-        if ((CNetAddr)pnode->addr == ip)
-            return (pnode);
+    for (CNode* pnode : vNodes) {
+        if ((CNetAddr)pnode->addr == ip) {
+            return pnode;
+        }
+    }
     return nullptr;
 }
 
 CNode* CConnman::FindNode(const CSubNet& subNet)
 {
     LOCK(cs_vNodes);
-    for (CNode* pnode : vNodes)
-    if (subNet.Match((CNetAddr)pnode->addr))
-        return (pnode);
+    for (CNode* pnode : vNodes) {
+        if (subNet.Match((CNetAddr)pnode->addr)) {
+            return pnode;
+        }
+    }
     return nullptr;
 }
 
@@ -329,7 +332,7 @@ CNode* CConnman::FindNode(const std::string& addrName)
     LOCK(cs_vNodes);
     for (CNode* pnode : vNodes) {
         if (pnode->GetAddrName() == addrName) {
-            return (pnode);
+            return pnode;
         }
     }
     return nullptr;
@@ -338,9 +341,11 @@ CNode* CConnman::FindNode(const std::string& addrName)
 CNode* CConnman::FindNode(const CService& addr)
 {
     LOCK(cs_vNodes);
-    for (CNode* pnode : vNodes)
-        if((CService)pnode->addr == addr)
-            return (pnode);
+    for (CNode* pnode : vNodes) {
+        if ((CService)pnode->addr == addr) {
+            return pnode;
+        }
+    }
     return nullptr;
 }
 
@@ -491,10 +496,9 @@ void CConnman::ClearBanned()
 bool CConnman::IsBanned(CNetAddr ip)
 {
     LOCK(cs_setBanned);
-    for (banmap_t::iterator it = setBanned.begin(); it != setBanned.end(); it++)
-    {
-        CSubNet subNet = (*it).first;
-        CBanEntry banEntry = (*it).second;
+    for (const auto& it : setBanned) {
+        CSubNet subNet = it.first;
+        CBanEntry banEntry = it.second;
 
         if (subNet.Match(ip) && GetTime() < banEntry.nBanUntil) {
             return true;
@@ -997,7 +1001,7 @@ bool CConnman::AttemptToEvictConnection()
     {
         LOCK(cs_vNodes);
 
-        for (CNode *node : vNodes) {
+        for (const CNode* node : vNodes) {
             if (node->fWhitelisted)
                 continue;
             if (!node->fInbound)
@@ -1095,9 +1099,9 @@ bool CConnman::AttemptToEvictConnection()
     // Disconnect from the network group with the most connections
     NodeId evicted = vEvictionCandidates.front().id;
     LOCK(cs_vNodes);
-    for(std::vector<CNode*>::const_iterator it(vNodes.begin()); it != vNodes.end(); ++it) {
-        if ((*it)->GetId() == evicted) {
-            (*it)->fDisconnect = true;
+    for (CNode* pnode : vNodes) {
+        if (pnode->GetId() == evicted) {
+            pnode->fDisconnect = true;
             return true;
         }
     }
@@ -1122,7 +1126,7 @@ void CConnman::AcceptConnection(const ListenSocket& hListenSocket) {
     bool whitelisted = hListenSocket.whitelisted || IsWhitelistedRange(addr);
     {
         LOCK(cs_vNodes);
-        for (CNode* pnode : vNodes) {
+        for (const CNode* pnode : vNodes) {
             if (pnode->fInbound) {
                 nInbound++;
                 if (!pnode->verifiedProRegTxHash.IsNull()) {
@@ -2021,8 +2025,7 @@ std::vector<AddedNodeInfo> CConnman::GetAddedNodeInfo()
     {
         LOCK(cs_vAddedNodes);
         ret.reserve(vAddedNodes.size());
-        for (const std::string& strAddNode : vAddedNodes)
-            lAddresses.push_back(strAddNode);
+        std::copy(vAddedNodes.cbegin(), vAddedNodes.cend(), std::back_inserter(lAddresses));
     }
 
 
@@ -2796,9 +2799,8 @@ std::vector<CAddress> CConnman::GetAddresses()
 bool CConnman::AddNode(const std::string& strNode)
 {
     LOCK(cs_vAddedNodes);
-    for(std::vector<std::string>::const_iterator it = vAddedNodes.begin(); it != vAddedNodes.end(); ++it) {
-        if (strNode == *it)
-            return false;
+    for (const std::string& it : vAddedNodes) {
+        if (strNode == it) return false;
     }
 
     vAddedNodes.push_back(strNode);
@@ -2924,9 +2926,11 @@ size_t CConnman::GetNodeCount(NumConnections flags)
         return vNodes.size();
 
     int nNum = 0;
-    for(std::vector<CNode*>::const_iterator it = vNodes.begin(); it != vNodes.end(); ++it)
-        if (flags & ((*it)->fInbound ? CONNECTIONS_IN : CONNECTIONS_OUT))
+    for (const auto& pnode : vNodes) {
+        if (flags & (pnode->fInbound ? CONNECTIONS_IN : CONNECTIONS_OUT)) {
             nNum++;
+        }
+    }
 
     return nNum;
 }
@@ -2941,8 +2945,7 @@ void CConnman::GetNodeStats(std::vector<CNodeStats>& vstats)
     vstats.clear();
     LOCK(cs_vNodes);
     vstats.reserve(vNodes.size());
-    for(std::vector<CNode*>::iterator it = vNodes.begin(); it != vNodes.end(); ++it) {
-        CNode* pnode = *it;
+    for (CNode* pnode : vNodes) {
         vstats.emplace_back();
         pnode->copyStats(vstats.back());
     }