diff --git a/src/agent/core/heartbeat.nim b/src/agent/core/heartbeat.nim
index 80173ef..d3a7c8c 100644
--- a/src/agent/core/heartbeat.nim
+++ b/src/agent/core/heartbeat.nim
@@ -11,7 +11,7 @@ proc createHeartbeat*(config: AgentConfig): Heartbeat =
             flags: cast[uint16](FLAG_ENCRYPTED),
             size: 0'u32,
             agentId: uuidToUint32(config.agentId),
-            seqNr: 0'u64,  
+            seqNr: 0'u32,  
             iv: generateIV(),
             gmac: default(AuthenticationTag)
         ), 
diff --git a/src/agent/nim.cfg b/src/agent/nim.cfg
index 46bb0c0..478904b 100644
--- a/src/agent/nim.cfg
+++ b/src/agent/nim.cfg
@@ -5,5 +5,5 @@
 -d:Octet3="0"
 -d:Octet4="1"
 -d:ListenerPort=9999
--d:SleepDelay=3
+-d:SleepDelay=10
 -d:ServerPublicKey="mi9o0kPu1ZSbuYfnG5FmDUMAvEXEvp11OW9CQLCyL1U="
diff --git a/src/common/sequence.nim b/src/common/sequence.nim
index 33b5aa6..4d1bb3a 100644
--- a/src/common/sequence.nim
+++ b/src/common/sequence.nim
@@ -1,21 +1,21 @@
 import tables 
 import ./[types, utils]
 
-var sequenceTable {.global.}: Table[uint32, uint64]
+var sequenceTable {.global.}: Table[uint32, uint32]
 
-proc nextSequence*(agentId: uint32): uint64 = 
-    sequenceTable[agentId] = sequenceTable.getOrDefault(agentId, 0'u64) + 1
+proc nextSequence*(agentId: uint32): uint32 = 
+    sequenceTable[agentId] = sequenceTable.getOrDefault(agentId, 0'u32) + 1
     return sequenceTable[agentId]
 
-proc validateSequence(agentId: uint32, seqNr: uint64, packetType: uint8): bool = 
-    let lastSeqNr = sequenceTable.getOrDefault(agentId, 0'u64)
+proc validateSequence(agentId: uint32, seqNr: uint32, packetType: uint8): bool = 
+    let lastSeqNr = sequenceTable.getOrDefault(agentId, 0'u32)
 
     # Heartbeat messages are not used for sequence tracking
     if cast[PacketType](packetType) == MSG_HEARTBEAT: 
         return true
 
     # In order to keep agents running after server restart, accept all connection with seqNr = 1, to update the table
-    if seqNr == 1'u64:
+    if seqNr == 1'u32:
         sequenceTable[agentId] = seqNr
         return true
 
diff --git a/src/common/serialize.nim b/src/common/serialize.nim
index 01b0043..1766a58 100644
--- a/src/common/serialize.nim
+++ b/src/common/serialize.nim
@@ -181,7 +181,7 @@ proc deserializeHeader*(unpacker: Unpacker): Header=
         flags: unpacker.getUint16(),
         size: unpacker.getUint32(),
         agentId: unpacker.getUint32(),
-        seqNr: unpacker.getUint64(),
+        seqNr: unpacker.getUint32(),
         iv: unpacker.getIv(),
         gmac: unpacker.getAuthenticationTag()
     )
diff --git a/src/common/types.nim b/src/common/types.nim
index 80fb19c..5bcb6b6 100644
--- a/src/common/types.nim
+++ b/src/common/types.nim
@@ -7,7 +7,7 @@ import streams
 const   
     MAGIC* = 0x514E3043'u32     # Magic value: C0NQ
     VERSION* = 1'u8             # Version 1
-    HEADER_SIZE* = 52'u8        # 48 bytes fixed packet header size
+    HEADER_SIZE* = 48'u8        # 48 bytes fixed packet header size
 
 type 
     PacketType* = enum 
@@ -69,33 +69,33 @@ type
         flags*: uint16              # [2 bytes ] message flags
         size*: uint32               # [4 bytes ] size of the payload body
         agentId*: uint32            # [4 bytes ] agent id, used as AAD for encryptio
-        seqNr*: uint64              # [8 bytes ] sequence number, used as AAD for encryption
+        seqNr*: uint32              # [4 bytes ] sequence number, used as AAD for encryption
         iv*: Iv                     # [12 bytes] random IV for AES256 GCM encryption
         gmac*: AuthenticationTag    # [16 bytes] authentication tag for AES256 GCM encryption
 
     TaskArg* = object 
-        argType*: uint8         # [1 byte  ] argument type
-        data*: seq[byte]        # variable length data (for variable data types (STRING, BINARY), the first 4 bytes indicate data length)
+        argType*: uint8             # [1 byte  ] argument type
+        data*: seq[byte]            # variable length data (for variable data types (STRING, BINARY), the first 4 bytes indicate data length)
 
     Task* = object 
         header*: Header
-        taskId*: uint32         # [4 bytes ] task id
-        listenerId*: uint32     # [4 bytes ] listener id
-        timestamp*: uint32      # [4 bytes ] unix timestamp
-        command*: uint16        # [2 bytes ] command id 
-        argCount*: uint8        # [1 byte  ] number of arguments
-        args*: seq[TaskArg]     # variable length arguments
+        taskId*: uint32             # [4 bytes ] task id
+        listenerId*: uint32         # [4 bytes ] listener id
+        timestamp*: uint32          # [4 bytes ] unix timestamp
+        command*: uint16            # [2 bytes ] command id 
+        argCount*: uint8            # [1 byte  ] number of arguments
+        args*: seq[TaskArg]         # variable length arguments
 
     TaskResult* = object 
         header*: Header 
-        taskId*: uint32         # [4 bytes ] task id
-        listenerId*: uint32     # [4 bytes ] listener id
-        timestamp*: uint32      # [4 bytes ] unix timestamp
-        command*: uint16        # [2 bytes ] command id 
-        status*: uint8          # [1 byte  ] success flag 
-        resultType*: uint8      # [1 byte  ] result data type (string, binary)
-        length*: uint32         # [4 bytes ] result length
-        data*: seq[byte]        # variable length result
+        taskId*: uint32             # [4 bytes ] task id
+        listenerId*: uint32         # [4 bytes ] listener id
+        timestamp*: uint32          # [4 bytes ] unix timestamp
+        command*: uint16            # [2 bytes ] command id 
+        status*: uint8              # [1 byte  ] success flag 
+        resultType*: uint8          # [1 byte  ] result data type (string, binary)
+        length*: uint32             # [4 bytes ] result length
+        data*: seq[byte]            # variable length result
 
 # Checkin binary structure
 type