Adding OpenConfig YANG models.

Change-Id: I0a2fdd5826e80933cf4b9ae939ff3051acec02aa
diff --git a/models/openconfig/src/main/yang/mpls/openconfig-mpls-ldp.yang b/models/openconfig/src/main/yang/mpls/openconfig-mpls-ldp.yang
new file mode 100644
index 0000000..b055d05
--- /dev/null
+++ b/models/openconfig/src/main/yang/mpls/openconfig-mpls-ldp.yang
@@ -0,0 +1,102 @@
+module openconfig-mpls-ldp {
+
+  yang-version "1";
+
+  // namespace
+  namespace "http://openconfig.net/yang/ldp";
+
+  prefix "ldp";
+
+  // import some basic types
+  import openconfig-extensions { prefix oc-ext; }
+
+  // meta
+  organization "OpenConfig working group";
+
+  contact
+    "OpenConfig working group
+    netopenconfig@googlegroups.com";
+
+  description
+    "Configuration of Label Distribution Protocol global and LSP-
+    specific parameters for IGP-congruent LSPs";
+
+  oc-ext:openconfig-version "2.4.0";
+
+  revision "2017-06-21" {
+    description
+      "Add TC bits typedef.";
+    reference "2.4.0";
+  }
+
+  revision "2017-03-22" {
+    description
+      "Add RSVP calculated-absolute-subscription-bw";
+    reference "2.3.0";
+  }
+
+  revision "2017-01-26" {
+    description
+      "Add RSVP Tspec, clarify units for RSVP, remove unused LDP";
+    reference "2.2.0";
+  }
+
+  revision "2016-12-15" {
+    description
+      "Add additional MPLS parameters";
+    reference "2.1.0";
+  }
+
+  revision "2016-09-01" {
+    description
+      "Revisions based on implementation feedback";
+    reference "2.0.0";
+  }
+
+  revision "2016-08-08" {
+    description
+      "Public release of MPLS models";
+    reference "1.0.1";
+  }
+
+  // grouping statements
+
+   grouping ldp-global {
+    description
+      "global LDP signaling configuration";
+
+    container ldp {
+      description
+        "LDP global signaling configuration";
+    }
+  }
+
+
+  grouping igp-tunnel-ldp {
+    description
+      "common defintiions for LDP-signaled LSP tunnel
+      types";
+  }
+
+  grouping igp-lsp-ldp-setup {
+    description
+      "grouping for LDP setup attributes";
+
+    container ldp {
+      description
+        "LDP signaling setup for IGP-congruent LSPs";
+
+      uses igp-tunnel-ldp;
+
+    }
+  }
+
+  // data definition statements
+
+  // augment statements
+
+  // rpc statements
+
+  // notification statements
+
+}