diff --git a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/Csnp.java b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/Csnp.java
index 80dc5b1..685be07 100644
--- a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/Csnp.java
+++ b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/Csnp.java
@@ -188,7 +188,9 @@
             TlvType tlvValue = TlvType.get(tlvHeader.tlvType());
             if (tlvValue != null) {
                 IsisTlv tlv = TlvFinder.findTlv(tlvHeader, channelBuffer.readBytes(tlvHeader.tlvLength()));
-                this.variableLengths.add(tlv);
+                if (tlv != null) {
+                    this.variableLengths.add(tlv);
+                }
             } else {
                 channelBuffer.readBytes(tlvHeader.tlvLength());
             }
diff --git a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/L1L2HelloPdu.java b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/L1L2HelloPdu.java
index 9737e1a..dd5eb7f 100644
--- a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/L1L2HelloPdu.java
+++ b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/L1L2HelloPdu.java
@@ -145,7 +145,9 @@
             TlvType tlvType = TlvType.get(tlvHeader.tlvType());
             if (tlvType != null) {
                 IsisTlv tlv = TlvFinder.findTlv(tlvHeader, channelBuffer.readBytes(tlvHeader.tlvLength()));
-                this.variableLengths.add(tlv);
+                if (tlv != null) {
+                    this.variableLengths.add(tlv);
+                }
             } else {
                 channelBuffer.readBytes(tlvHeader.tlvLength());
             }
diff --git a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/LsPdu.java b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/LsPdu.java
index f6bd85c..b7c40a3 100644
--- a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/LsPdu.java
+++ b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/LsPdu.java
@@ -354,7 +354,9 @@
             TlvType tlvValue = TlvType.get(tlvHeader.tlvType());
             if (tlvValue != null) {
                 IsisTlv tlv = TlvFinder.findTlv(tlvHeader, channelBuffer.readBytes(tlvHeader.tlvLength()));
-                this.variableLengths.add(tlv);
+                if (tlv != null) {
+                    this.variableLengths.add(tlv);
+                }
             } else {
                 channelBuffer.readBytes(tlvHeader.tlvLength());
             }
diff --git a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/P2PHelloPdu.java b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/P2PHelloPdu.java
index e236610..cb5bd05 100644
--- a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/P2PHelloPdu.java
+++ b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/pdu/P2PHelloPdu.java
@@ -124,7 +124,9 @@
             TlvType tlvType = TlvType.get(tlvHeader.tlvType());
             if (tlvType != null) {
                 IsisTlv tlv = TlvFinder.findTlv(tlvHeader, channelBuffer.readBytes(tlvHeader.tlvLength()));
-                this.variableLengths.add(tlv);
+                if (tlv != null) {
+                    this.variableLengths.add(tlv);
+                }
             } else {
                 channelBuffer.readBytes(tlvHeader.tlvLength());
             }
diff --git a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/IpExtendedReachabilityTlv.java b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/IpExtendedReachabilityTlv.java
index f1549e4..90b79cc 100644
--- a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/IpExtendedReachabilityTlv.java
+++ b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/IpExtendedReachabilityTlv.java
@@ -205,8 +205,11 @@
                 tlvHeader.setTlvLength(channelBuffer.readByte());
                 SubTlvType tlvValue = SubTlvType.get(tlvHeader.tlvType());
                 if (tlvValue != null) {
-                    this.addSubTlv(SubTlvFinder.findSubTlv(tlvHeader,
-                                                           channelBuffer.readBytes(tlvHeader.tlvLength())));
+                    TrafficEngineeringSubTlv subTlv =
+                            SubTlvFinder.findSubTlv(tlvHeader, channelBuffer.readBytes(tlvHeader.tlvLength()));
+                    if (subTlv != null) {
+                        this.addSubTlv(subTlv);
+                    }
                 } else {
                     channelBuffer.readBytes(tlvHeader.tlvLength());
                 }
diff --git a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/IsExtendedReachability.java b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/IsExtendedReachability.java
index b2eb6c9..d8e75b1 100644
--- a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/IsExtendedReachability.java
+++ b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/IsExtendedReachability.java
@@ -49,9 +49,10 @@
         this.neighbors.add(neighbor);
     }
 
+
     @Override
     public void readFrom(ChannelBuffer channelBuffer) {
-        while (channelBuffer.readableBytes() >= IsisUtil.EIGHT_BYTES + IsisUtil.THREE_BYTES) {
+        while (channelBuffer.readableBytes() >= (IsisUtil.EIGHT_BYTES + IsisUtil.THREE_BYTES)) {
             NeighborForExtendedIs extendedIs = new NeighborForExtendedIs();
             extendedIs.readFrom(channelBuffer);
             this.addNeighbor(extendedIs);
diff --git a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/LspEntriesTlv.java b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/LspEntriesTlv.java
index e43d4b4..02199d4 100644
--- a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/LspEntriesTlv.java
+++ b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/LspEntriesTlv.java
@@ -18,6 +18,7 @@
 import com.google.common.base.MoreObjects;
 import com.google.common.primitives.Bytes;
 import org.jboss.netty.buffer.ChannelBuffer;
+import org.onosproject.isis.io.util.IsisUtil;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -58,9 +59,9 @@
 
     @Override
     public void readFrom(ChannelBuffer channelBuffer) {
-        while (channelBuffer.readableBytes() >= 16) {
+        while (channelBuffer.readableBytes() >= (IsisUtil.EIGHT_BYTES * 2)) {
             LspEntry lspEntry = new LspEntry();
-            lspEntry.readFrom(channelBuffer.readBytes(16));
+            lspEntry.readFrom(channelBuffer.readBytes(IsisUtil.EIGHT_BYTES * 2));
             lspEntryList.add(lspEntry);
         }
     }
diff --git a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/NeighborForExtendedIs.java b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/NeighborForExtendedIs.java
index 88b8462..0bc57b4 100644
--- a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/NeighborForExtendedIs.java
+++ b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/tlv/NeighborForExtendedIs.java
@@ -101,8 +101,11 @@
                 int tlvLength = tlvHeader.tlvLength();
                 if (tlvValue != null) {
                     if (channelBuffer.readableBytes() >= tlvLength) {
-                        this.addSubTlv(SubTlvFinder.findSubTlv(tlvHeader,
-                                                               channelBuffer.readBytes(tlvHeader.tlvLength())));
+                        TrafficEngineeringSubTlv subTlv =
+                                SubTlvFinder.findSubTlv(tlvHeader, channelBuffer.readBytes(tlvHeader.tlvLength()));
+                        if (subTlv != null) {
+                            this.addSubTlv(subTlv);
+                        }
                     }
                 } else {
                     if (channelBuffer.readableBytes() >= tlvLength) {