# UNDF: UNDF-2026-000001016
--- a/iroh-relay/src/main.rs
+++ b/iroh-relay/src/main.rs
@@ -6,6 +6,7 @@
 use std::{
+    collections::HashSet,
     net::{Ipv6Addr, SocketAddr},
     num::NonZeroU32,
     path::{Path, PathBuf},
@@ -150,9 +151,9 @@
 enum AccessConfig {
     /// Allows everyone
     #[default]
     Everyone,
     /// Allows only these endpoints.
-    Allowlist(Vec<EndpointId>),
+    Allowlist(HashSet<EndpointId>),
     /// Allows everyone, except these endpoints.
-    Denylist(Vec<EndpointId>),
+    Denylist(HashSet<EndpointId>),
     /// Performs a HTTP POST request to determine access for each endpoint that connects to the relay.
     ///
     /// The request will have a header `X-Iroh-Endpoint-Id` set to the hex-encoded endpoint id attempting