diff --git a/src/definitions/SOL002SOL003VNFLifecycleManagement_def.yaml b/src/definitions/SOL002SOL003VNFLifecycleManagement_def.yaml
index bf91bbf11921e85808137397c8555836ba75a7c8..a59902a54ac94bb3b2559c8218a0267fc5e565e5 100644
--- a/src/definitions/SOL002SOL003VNFLifecycleManagement_def.yaml
+++ b/src/definitions/SOL002SOL003VNFLifecycleManagement_def.yaml
@@ -231,12 +231,11 @@ definitions:
       This type represents information about a network address that has been
       assigned. 
     type: object
-    required: 
-      - macAddress
     properties: 
       macAddress:
         description: >
-          Assigned MAC address.
+          MAC address, if assigned.
+          At least one of "macAddress" or "ipAddresses" shall be present.
         $ref: "SOL002SOL003_def.yaml#/definitions/MacAddress"
       ipAddresses:
         description: >
@@ -261,6 +260,7 @@ definitions:
               description: >
                 Fixed addresses assigned (from the subnet defined by
                 "subnetId" if provided).
+                Exactly one of "addresses" or "addressRange" shall be present.
               type: array
               items: 
                 $ref: "SOL002SOL003_def.yaml#/definitions/IpAddress"