diff --git a/proto/pathcomp.proto b/proto/pathcomp.proto
index 2570456bba28fd4baa02628aedabed1cc63db10a..9eb650fb9981b4b84f31b63796eec0c7a8e780b6 100644
--- a/proto/pathcomp.proto
+++ b/proto/pathcomp.proto
@@ -21,8 +21,19 @@ service PathCompService {
   rpc Compute(PathCompRequest) returns (PathCompReply) {}
 }
 
+message Algorithm_ShortestPath {}
+
+message Algorithm_KShortestPath {
+  uint32 k_inspection = 1;
+  uint32 k_return     = 2;
+}
+
 message PathCompRequest {
   repeated context.Service services = 1;
+  oneof algorithm {
+    Algorithm_ShortestPath  shortest_path   = 10;
+    Algorithm_KShortestPath k_shortest_path = 11;
+  }
 }
 
 message PathCompReply {
diff --git a/src/pathcomp/service/PathCompServiceServicerImpl.py b/src/pathcomp/service/PathCompServiceServicerImpl.py
index 1bb4470b1c2863a04e7be2816f250e5e42fcb500..e1c7251508ea767a38d3102cca8f4edd50cf9170 100644
--- a/src/pathcomp/service/PathCompServiceServicerImpl.py
+++ b/src/pathcomp/service/PathCompServiceServicerImpl.py
@@ -38,6 +38,8 @@ class PathCompServiceServicerImpl(PathCompServiceServicer):
 
         context_client = ContextClient()
 
+        # TODO: consider filtering resources
+
         grpc_contexts = context_client.ListContexts(Empty())
         grpc_devices = context_client.ListDevices(Empty())
         grpc_links = context_client.ListLinks(Empty())
diff --git a/src/pathcomp/tests/Objects.py b/src/pathcomp/tests/Objects.py
index a3cf10b789d0fa7cb6fd3fdf3e2802dcb6024ec8..f4785d7ae670efcc5525d6b00c4baf3acf3f22b1 100644
--- a/src/pathcomp/tests/Objects.py
+++ b/src/pathcomp/tests/Objects.py
@@ -93,8 +93,8 @@ LINK_C2_C3_ID, LINK_C2_C3 = compose_link(DEVICE_C2_ENDPOINTS[1], DEVICE_C3_ENDPO
 
 # ----- Service --------------------------------------------------------------------------------------------------------
 SERVICE_A1_B1 = compose_service(DEVICE_A1_ENDPOINTS[2], DEVICE_B1_ENDPOINTS[2], constraints=[
-    json_constraint('bandwidth', 10.0),
-    json_constraint('latency_ms', 5.0)
+    json_constraint('bandwidth[gbps]', 10.0),
+    json_constraint('latency[ms]',      5.0),
 ])
 
 # ----- Containers -----------------------------------------------------------------------------------------------------