diff --git a/schema/lib/elements/he_ipv6.xsd b/schema/lib/elements/he_ipv6.xsd
index a443d3c..4f1118e 100644
--- a/schema/lib/elements/he_ipv6.xsd
+++ b/schema/lib/elements/he_ipv6.xsd
@@ -10,6 +10,7 @@
   <xs:complexType name="e_he_ipv6_cred">
     <xs:all>
       <xs:element name="user" type="xs:token" minOccurs="1"/>
+      <xs:element name="password" type="xs:token" minOccurs="1"/>
       <xs:element name="updateKey" type="xs:token" minOccurs="1"/>
     </xs:all>
     <xs:attribute name="id" type="xs:ID" use="required"/>
@@ -17,55 +18,13 @@
 
   <xs:complexType name="e_he_ipv6_tunnel">
     <xs:all>
-      <xs:element name="server" type="t_net_addr_ip4"/>
-      <xs:element name="client" minOccurs="1" maxOccurs="1">
-        <xs:complexType>
-          <xs:simpleContent>
-            <xs:extension base="t_net_addr_ip6">
-              <!-- VERY most likely "64" but we can't define a default with required. -->
-              <xs:attribute name="prefix" type="t_he_ipv6_prefix" use="required"/>
-            </xs:extension>
-          </xs:simpleContent>
-        </xs:complexType>
-      </xs:element>
-      <xs:element name="allocations">
-        <xs:complexType>
-          <xs:sequence minOccurs="1">
-            <!-- HE only allocates a single /64 and, upon request, a single /48 per tunnel. -->
-            <xs:element name="alloc" minOccurs="1" maxOccurs="2">
-              <xs:complexType>
-                <xs:simpleContent>
-                  <xs:extension base="t_net_addr_ip6">
-                    <!-- VERY most likely "64" but we can't define a default with required. -->
-                    <xs:attribute name="prefix" type="t_he_ipv6_prefix" use="required"/>
-                    <xs:attribute name="id" type="xs:token" use="required"/>
-                  </xs:extension>
-                </xs:simpleContent>
-              </xs:complexType>
-            </xs:element>
-          </xs:sequence>
-        </xs:complexType>
-        <xs:unique name="uniq_alloc_addr">
-          <xs:selector xpath=".//*"/>
-          <xs:field xpath="."/>
-        </xs:unique>
-        <xs:unique name="uniq_alloc_prefix">
-          <xs:selector xpath=".//*"/>
-          <xs:field xpath="@prefix"/>
-        </xs:unique>
-        <xs:unique name="uniq_alloc_id">
-          <xs:selector xpath=".//*"/>
-          <xs:field xpath="@id"/>
-        </xs:unique>
-      </xs:element>
       <xs:element name="assignments" minOccurs="1" maxOccurs="1">
         <xs:complexType>
           <xs:sequence minOccurs="1" maxOccurs="unbounded">
             <xs:element name="assign" minOccurs="1" maxOccurs="unbounded">
               <xs:complexType>
-                <xs:attribute name="prefix" type="t_he_ipv6_prefix" use="optional" default="64"/>
-                <!-- TODO: alloc must be a defined alloc "id" attribute value. -->
-                <xs:attribute name="alloc" type="xs:token" use="required"/>
+                <xs:attribute name="prefix" type="t_he_ipv6_prefix_local" use="optional" default="64"/>
+                <xs:attribute name="alloc" type="t_he_ipv6_prefix" use="optional" default="64"/>
                 <xs:attribute name="iface" type="t_linux_iface_name" use="required"/>
               </xs:complexType>
             </xs:element>
@@ -73,6 +32,12 @@
           <xs:attribute name="radvd" type="xs:boolean" use="optional" default="false"/>
           <xs:attribute name="radvdDns" type="xs:boolean" use="optional" default="false"/>
         </xs:complexType>
+        <xs:unique name="uniq_he_assign">
+          <xs:selector xpath=".//*"/>
+          <!-- <xs:field xpath="@prefix"/> -->
+          <xs:field xpath="@alloc"/>
+          <xs:field xpath="@iface"/>
+        </xs:unique>
       </xs:element>
     </xs:all>
     <xs:attribute name="id" type="xs:positiveInteger" use="required"/>
diff --git a/schema/lib/types/he_ipv6.xsd b/schema/lib/types/he_ipv6.xsd
index e8e5c4c..a663f61 100644
--- a/schema/lib/types/he_ipv6.xsd
+++ b/schema/lib/types/he_ipv6.xsd
@@ -10,4 +10,11 @@
     </xs:restriction>
   </xs:simpleType>
 
+  <xs:simpleType name="t_he_ipv6_prefix_local">
+    <xs:restriction base="xs:positiveInteger">
+      <xs:minInclusive value="64"/>
+      <xs:maxInclusive value="128"/>
+    </xs:restriction>
+  </xs:simpleType>
+
 </xs:schema>
diff --git a/schema/projects/he_ipv6.xsd b/schema/projects/he_ipv6.xsd
index 535b22f..0febd48 100644
--- a/schema/projects/he_ipv6.xsd
+++ b/schema/projects/he_ipv6.xsd
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8" ?>
 <xs:schema targetNamespace="https://tunnelbroker.net/"
            xmlns="https://tunnelbroker.net/"
-           xmlns:heIPv6="https://tunelbroker.net/"
+           xmlns:heIPv6="https://tunnelbroker.net/"
            xmlns:xs="http://www.w3.org/2001/XMLSchema"
            elementFormDefault="qualified"
            attributeFormDefault="unqualified">