diff --git a/example-data/nfv-nsd.xml b/example-data/nfv-nsd.xml
index 8241604b3de85cceebabf22952d6f8866c32f056..c52f36ddc6ee64f55dc979e19032a10eb87af8ba 100644
--- a/example-data/nfv-nsd.xml
+++ b/example-data/nfv-nsd.xml
@@ -1,3 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
 <nfv xmlns="urn:etsi:nfv:yang:etsi-nfv-descriptors">
   <vnfd>
     <id>ASA</id>
diff --git a/src/yang/etsi-nfv-nsd.yang b/src/yang/etsi-nfv-nsd.yang
index 304fc30e19f93ead8831dc49a57dd6d382b9f85a..0175854eb6ce811c9e37cb5a7869cc61f0d87af6 100644
--- a/src/yang/etsi-nfv-nsd.yang
+++ b/src/yang/etsi-nfv-nsd.yang
@@ -30,8 +30,10 @@ module etsi-nfv-nsd {
   container nsd {
     list nsd {
       key "id";
+
       max-elements 1;
       uses nfv:nsd;
+
       description
 	"The NSD information element is a deployment template whose
          instances are used by the NFVO for the lifecycle management
diff --git a/src/yang/etsi-nfv-vnf.yang b/src/yang/etsi-nfv-vnf.yang
index 2fcc971d6ac52e5b01af583ef12bba8337c7d87e..c1586980ddc9b52b3c02bd8e87984b9bb866b5f2 100755
--- a/src/yang/etsi-nfv-vnf.yang
+++ b/src/yang/etsi-nfv-vnf.yang
@@ -95,6 +95,23 @@ submodule etsi-nfv-vnf {
           "GS NFV-IFA011: Section 7.1.6.6,
            VirtualNetworkInterfaceRequirements information element";
       }
+
+      leaf nic-io-requirements {
+	type leafref {
+          path "/nfv:nfv/nfv:vnfd/nfv:virtual-compute-desc/" +
+	       "nfv:logical-node/nfv:id";
+	}
+	description
+	  "This references (couples) the CPD with any logical node
+           I/O requirements (for network devices) that may have been
+           created. Linking these attributes is necessary so that I/O
+           requirements that need to be articulated at the logical
+           node level can be associated with the network interface
+           requirements associated with the CPD.";
+        reference
+          "GS NFV-IFA011: Section 7.1.6.6,
+           VirtualNetworkInterfaceRequirements information element";
+      }
     }
   }
 
@@ -491,6 +508,7 @@ submodule etsi-nfv-vnf {
 
         list requirement-detail {
           key "key";
+          min-elements 1;
 
           leaf key {
             type string;