diff --git a/gradle/configure.gradle b/gradle/configure.gradle
index 5db3e21..cac4a30 100644
--- a/gradle/configure.gradle
+++ b/gradle/configure.gradle
@@ -7,7 +7,7 @@ ext {
 
 	NAME = 'Jxpacket'
 	GROUP = 'com.ardikars.jxpacket'
-	VERSION = '1.2.3.RC2'
+	VERSION = '1.2.3.RC4'
 	DESCRIPTION = 'Jxpacket is a network packet crafting library for java.'
 
 	MAVEN_LOCAL_REPOSITORY = "${System.env.HOME}/.m2/repository"
diff --git a/jxpacket-core/src/main/java/com/ardikars/jxpacket/core/ip/Ip4.java b/jxpacket-core/src/main/java/com/ardikars/jxpacket/core/ip/Ip4.java
index 2bc8972..c958b18 100644
--- a/jxpacket-core/src/main/java/com/ardikars/jxpacket/core/ip/Ip4.java
+++ b/jxpacket-core/src/main/java/com/ardikars/jxpacket/core/ip/Ip4.java
@@ -154,7 +154,7 @@ public byte[] getOptions() {
 		public boolean isValidChecksum() {
 			int accumulation = 0;
 			for (int i = 0; i < headerLength * 2; ++i) {
-				accumulation += 0xffff & buffer.getShort(0);
+				accumulation += 0xffff & buffer.getShort(i + 2);
 			}
 			accumulation = (accumulation >> 16 & 0xffff)
 					+ (accumulation & 0xffff);
diff --git a/jxpacket-core/src/main/java/com/ardikars/jxpacket/core/tcp/Tcp.java b/jxpacket-core/src/main/java/com/ardikars/jxpacket/core/tcp/Tcp.java
index 3f0bd8c..b77d1e4 100644
--- a/jxpacket-core/src/main/java/com/ardikars/jxpacket/core/tcp/Tcp.java
+++ b/jxpacket-core/src/main/java/com/ardikars/jxpacket/core/tcp/Tcp.java
@@ -272,23 +272,23 @@ public Packet build() {
 
         @Override
         public Packet build(Memory buffer) {
-            this.sourcePort = buffer.getShort(0);
-            this.destinationPort = buffer.getShort(2);
-            this.sequence = buffer.getInt(4);
-            this.acknowledge = buffer.getInt(8);
-            short flags = buffer.getShort(12);
+            this.sourcePort = buffer.readShort();
+            this.destinationPort = buffer.readShort();
+            this.sequence = buffer.readInt();
+            this.acknowledge = buffer.readInt();
+            short flags = buffer.readShort();
             this.dataOffset = (byte) (flags >> 12 & 0xf);
             this.flags = new TcpFlags.Builder().build((short) (flags & 0x1ff));
-            this.windowSize = buffer.getShort(14);
-            this.checksum = buffer.getShort(16);
-            this.urgentPointer = buffer.getShort(18);
+            this.windowSize = buffer.readShort();
+            this.checksum = buffer.readShort();
+            this.urgentPointer = buffer.readShort();
             if (this.dataOffset > 5) {
                 int optionLength = (this.dataOffset << 2) - Header.TCP_HEADER_LENGTH;
                 if (buffer.capacity() < Header.TCP_HEADER_LENGTH + optionLength) {
                     optionLength = buffer.capacity() - Header.TCP_HEADER_LENGTH;
                 }
                 this.options = new byte[optionLength];
-                buffer.getBytes(20, options);
+                buffer.readBytes(options);
                 int length = 20 + optionLength;
                 this.payloadBuffer = buffer.copy(length, buffer.capacity() - length);
             }
diff --git a/jxpacket-core/src/main/java/com/ardikars/jxpacket/core/udp/Udp.java b/jxpacket-core/src/main/java/com/ardikars/jxpacket/core/udp/Udp.java
index 420f7f1..3fdc75a 100644
--- a/jxpacket-core/src/main/java/com/ardikars/jxpacket/core/udp/Udp.java
+++ b/jxpacket-core/src/main/java/com/ardikars/jxpacket/core/udp/Udp.java
@@ -165,10 +165,10 @@ public Packet build() {
 
         @Override
         public Packet build(Memory buffer) {
-            this.sourcePort = buffer.getShort(0);
-            this.destinationPort = buffer.getShort(2);
-            this.length = buffer.getShort(4);
-            this.checksum = buffer.getShort(6);
+            this.sourcePort = buffer.readShort();
+            this.destinationPort = buffer.readShort();
+            this.length = buffer.readShort();
+            this.checksum = buffer.readShort();
             this.buffer = buffer;
             this.payloadBuffer = buffer.slice();
             return new Udp(this);