diff --git a/examples/abitest/module_0/rust/src/lib.rs b/examples/abitest/module_0/rust/src/lib.rs
index 6bf989b2c61..d8c1863d7de 100644
--- a/examples/abitest/module_0/rust/src/lib.rs
+++ b/examples/abitest/module_0/rust/src/lib.rs
@@ -122,7 +122,7 @@ impl FrontendNode {
             }),
             misconfigured_roughtime: oak::roughtime::Roughtime::new(
                 &RoughtimeClientConfiguration {
-                    min_overlapping_intervals: 99,
+                    min_overlapping_intervals: Some(99),
                     ..Default::default()
                 },
             ),
diff --git a/oak/proto/BUILD b/oak/proto/BUILD
index c8595859396..6a719e62ab8 100644
--- a/oak/proto/BUILD
+++ b/oak/proto/BUILD
@@ -27,6 +27,7 @@ package(
 proto_library(
     name = "application_proto",
     srcs = ["application.proto"],
+    deps = ["@com_google_protobuf//:wrappers_proto"],
 )
 
 cc_proto_library(
diff --git a/oak/proto/application.proto b/oak/proto/application.proto
index d8dedd1c50c..b940d56aae1 100644
--- a/oak/proto/application.proto
+++ b/oak/proto/application.proto
@@ -18,6 +18,8 @@ syntax = "proto3";
 
 package oak.application;
 
+import "google/protobuf/wrappers.proto";
+
 // An ApplicationConfiguration represents a unit of deployment in Oak.
 //
 // A running Oak Application instance is built from a collection of
@@ -118,11 +120,11 @@ message RoughtimeClientConfiguration {
   // will be used if this is empty.
   repeated RoughtimeServer servers = 1;
   // Connection parameters; default values will be used if any parameter is
-  // zero.
-  uint32 min_overlapping_intervals = 2;
-  uint32 timeout_seconds = 3;
-  uint32 server_retries = 4;
-  uint32 max_radius_microseconds = 5;
+  // unset.
+  google.protobuf.UInt32Value min_overlapping_intervals = 2;
+  google.protobuf.UInt32Value timeout_seconds = 3;
+  google.protobuf.UInt32Value server_retries = 4;
+  google.protobuf.UInt32Value max_radius_microseconds = 5;
 }
 
 // Information to identify a particular Roughtime server.
diff --git a/oak/proto/roughtime_service.proto b/oak/proto/roughtime_service.proto
index ffcce1dc0d6..c4cef8eec5e 100644
--- a/oak/proto/roughtime_service.proto
+++ b/oak/proto/roughtime_service.proto
@@ -18,9 +18,9 @@ syntax = "proto3";
 
 package oak.roughtime;
 
-message RoughtimeRequest {}
+message GetRoughtimeRequest {}
 
-message RoughtimeResponse {
+message Roughtime {
   // Time is UTC and is given as microseconds since the UNIX epoch (00:00:00 UTC
   // on 1 January 1970). Leap seconds are linearly smeared over a 24-hour
   // period. That is, the smear extends from UTC noon to noon over 86,401 or
@@ -31,5 +31,5 @@ message RoughtimeResponse {
 // Interface exposed by the Roughtime client pseudo-Node to other nodes over a
 // pair of Oak Channels.
 service RoughtimeService {
-  rpc GetRoughtime(RoughtimeRequest) returns (RoughtimeResponse);
+  rpc GetRoughtime(GetRoughtimeRequest) returns (Roughtime);
 }
diff --git a/oak/server/rust/oak_runtime/src/node/roughtime.rs b/oak/server/rust/oak_runtime/src/node/roughtime.rs
index 38dbb4b9259..f2752f190bf 100644
--- a/oak/server/rust/oak_runtime/src/node/roughtime.rs
+++ b/oak/server/rust/oak_runtime/src/node/roughtime.rs
@@ -32,7 +32,7 @@ use oak_abi::{
         oak::{
             application::RoughtimeClientConfiguration,
             encap::GrpcResponse,
-            roughtime::{RoughtimeRequest, RoughtimeResponse},
+            roughtime::{GetRoughtimeRequest, Roughtime},
         },
     },
     OakStatus,
@@ -49,26 +49,18 @@ pub struct RoughtimeClientNode {
 impl RoughtimeClientNode {
     /// Creates a new [`RoughtimeClientNode`] instance, but does not start it.
     pub fn new(node_name: &str, config: &RoughtimeClientConfiguration) -> Self {
-        let timeout_seconds = if config.timeout_seconds == 0 {
-            DEFAULT_TIMEOUT_SECONDS
-        } else {
-            config.timeout_seconds as u64
-        };
-        let server_retries = if config.server_retries == 0 {
-            DEFAULT_SERVER_RETRIES
-        } else {
-            config.server_retries as usize
-        };
-        let min_overlapping_intervals = if config.min_overlapping_intervals == 0 {
-            DEFAULT_MIN_OVERLAPPING_INTERVALS
-        } else {
-            config.min_overlapping_intervals as usize
-        };
-        let max_radius_microseconds = if config.max_radius_microseconds == 0 {
-            DEFAULT_MAX_RADIUS_MICROSECONDS
-        } else {
-            config.max_radius_microseconds
-        };
+        let timeout_seconds = config
+            .timeout_seconds
+            .map_or(DEFAULT_TIMEOUT_SECONDS, |value| value as u64);
+        let server_retries = config
+            .server_retries
+            .map_or(DEFAULT_SERVER_RETRIES, |value| value as usize);
+        let min_overlapping_intervals = config
+            .min_overlapping_intervals
+            .map_or(DEFAULT_MIN_OVERLAPPING_INTERVALS, |value| value as usize);
+        let max_radius_microseconds = config
+            .max_radius_microseconds
+            .unwrap_or(DEFAULT_MAX_RADIUS_MICROSECONDS);
         let servers = if config.servers.is_empty() {
             get_default_servers()
         } else {
@@ -102,11 +94,12 @@ impl RoughtimeClientNode {
     fn process_invocation(&self, runtime: &RuntimeProxy, invocation: &Invocation) {
         match invocation.receive_request(runtime) {
             Ok(request) => {
+                // TODO(#1113): Generate this code automatically.
                 if request.method_name != "/oak.roughtime.RoughtimeService/GetRoughtime" {
                     let message = format!("Unknown method_name: {}", request.method_name);
                     invocation.send_error(Code::NotFound, &message, runtime);
                 }
-                if RoughtimeRequest::decode(request.req_msg.as_slice()).is_err() {
+                if GetRoughtimeRequest::decode(request.req_msg.as_slice()).is_err() {
                     invocation.send_error(
                         Code::InvalidArgument,
                         "Could not parse request.",
@@ -122,7 +115,7 @@ impl RoughtimeClientNode {
 
         match self.client.get_roughtime() {
             Ok(time) => {
-                let response = RoughtimeResponse {
+                let response = Roughtime {
                     roughtime_usec: time,
                 };
                 let mut message = Vec::new();
diff --git a/sdk/rust/oak/src/roughtime/mod.rs b/sdk/rust/oak/src/roughtime/mod.rs
index c1ab272cbae..274b61386e3 100644
--- a/sdk/rust/oak/src/roughtime/mod.rs
+++ b/sdk/rust/oak/src/roughtime/mod.rs
@@ -18,7 +18,7 @@
 
 use crate::{
     grpc,
-    proto::oak::roughtime::{RoughtimeRequest, RoughtimeServiceClient},
+    proto::oak::roughtime::{GetRoughtimeRequest, RoughtimeServiceClient},
 };
 use oak_abi::proto::oak::application::{
     node_configuration::ConfigType, NodeConfiguration, RoughtimeClientConfiguration,
@@ -44,7 +44,7 @@ impl Roughtime {
     /// Get the current Roughtime value as a Duration since UNIX epoch.
     /// Note that leap seconds are linearly smeared over 24h.
     pub fn get_roughtime(&self) -> grpc::Result<std::time::Duration> {
-        let rsp = self.client.get_roughtime(RoughtimeRequest {})?;
+        let rsp = self.client.get_roughtime(GetRoughtimeRequest {})?;
         Ok(std::time::Duration::from_micros(rsp.roughtime_usec))
     }
 }