diff --git a/xCAT-test/unit/dhcp_boot_policy.t b/xCAT-test/unit/dhcp_boot_policy.t
index 8b0f823ae..b5369b066 100644
--- a/xCAT-test/unit/dhcp_boot_policy.t
+++ b/xCAT-test/unit/dhcp_boot_policy.t
@@ -81,4 +81,64 @@ my $combined_classes = xCAT::DHCP::BootPolicy->kea_client_classes(
 );
 is( $combined_classes->[0]{name}, 'xcat-xnba-cn01-52544b100011-bios', 'node-specific xNBA classes have priority over generic boot classes' );
 
+my $network_classes = xCAT::DHCP::BootPolicy->kea_xnba_network_classes(
+    net         => '192.0.2.0',
+    prefix      => 24,
+    next_server => '192.0.2.10',
+    httpport    => '8080',
+    xnba_kpxe   => 1,
+    xnba_efi    => 1,
+);
+is( scalar @$network_classes, 2, 'xNBA network policy renders BIOS and UEFI fallback classes' );
+my %network_by_name = map { $_->{name} => $_ } @$network_classes;
+my $network_bios = $network_by_name{'xcat-xnba-net-192.0.2.0_24-bios'};
+ok( $network_bios, 'xNBA network BIOS class is named by subnet' );
+is(
+    $network_bios->{'boot-file-name'},
+    'http://192.0.2.10:8080/tftpboot/xcat/xnba/nets/192.0.2.0_24',
+    'xNBA network BIOS class returns the subnet script URL'
+);
+like( $network_bios->{test}, qr/option\[77\]\.text == 'xNBA'/, 'xNBA network class matches the xNBA user class' );
+like( $network_bios->{test}, qr/option\[93\]\.hex == 0x0000/, 'xNBA network BIOS class matches BIOS clients' );
+unlike( $network_bios->{test}, qr/pkt4\.mac/, 'xNBA network fallback does not require a known MAC' );
+ok( $network_bios->{additional_only}, 'xNBA network fallback is limited to its owning subnet' );
+is(
+    $network_by_name{'xcat-xnba-net-192.0.2.0_24-uefi'}{'boot-file-name'},
+    'http://192.0.2.10:8080/tftpboot/xcat/xnba/nets/192.0.2.0_24.uefi',
+    'xNBA network UEFI class returns the subnet UEFI script URL'
+);
+like(
+    $network_by_name{'xcat-xnba-net-192.0.2.0_24-uefi'}{test},
+    qr/0x0010/,
+    'xNBA network UEFI class matches HTTP boot clients'
+);
+
+is_deeply(
+    xCAT::DHCP::BootPolicy->kea_xnba_network_classes(
+        net         => '192.0.2.0',
+        prefix      => 24,
+        next_server => '192.0.2.10',
+        xnba_kpxe   => 1,
+    ),
+    [
+        {
+            name             => 'xcat-xnba-net-192.0.2.0_24-bios',
+            test             => xCAT::DHCP::BootPolicy::xnba_user_class_test()
+              . ' and option[93].hex == 0x0000',
+            'boot-file-name' => 'http://192.0.2.10/tftpboot/xcat/xnba/nets/192.0.2.0_24',
+            additional_only  => 1,
+        },
+    ],
+    'xNBA network policy omits unavailable loaders and the default HTTP port'
+);
+is_deeply(
+    xCAT::DHCP::BootPolicy->kea_xnba_network_classes(
+        net       => '192.0.2.0',
+        prefix    => 24,
+        xnba_kpxe => 1,
+    ),
+    [],
+    'xNBA network policy requires a next server'
+);
+
 done_testing();
diff --git a/xCAT-test/unit/dhcp_kea_renderer.t b/xCAT-test/unit/dhcp_kea_renderer.t
index 89ae04cfb..af20211d5 100644
--- a/xCAT-test/unit/dhcp_kea_renderer.t
+++ b/xCAT-test/unit/dhcp_kea_renderer.t
@@ -194,6 +194,37 @@ ok( !exists $modern_subnet->{'require-client-classes'}, 'Kea 3.x output omits de
 is( $modern_class->{'only-in-additional-list'}, JSON::true, 'Kea 3.x renders modern class additional-evaluation flag' );
 ok( !exists $modern_class->{'only-if-required'}, 'Kea 3.x output omits deprecated class additional-evaluation flag' );
 
+my $numeric_additional_json = $backend->render_dhcp4_config(
+    {
+        subnets => [
+            {
+                id                        => 4,
+                subnet                    => '192.0.2.0/24',
+                pools                     => [],
+                additional_client_classes => ['xcat-xnba-net-192.0.2.0_24-bios'],
+            },
+        ],
+        'client-classes' => [
+            {
+                name            => 'xcat-xnba-net-192.0.2.0_24-bios',
+                test            => "option[77].text == 'xNBA'",
+                additional_only => 1,
+            },
+        ],
+    }
+);
+my $numeric_additional_config = decode_json($numeric_additional_json);
+is_deeply(
+    $numeric_additional_config->{Dhcp4}{subnet4}[0]{'require-client-classes'},
+    ['xcat-xnba-net-192.0.2.0_24-bios'],
+    'legacy Kea limits the xNBA fallback class to its owning subnet'
+);
+is(
+    $numeric_additional_config->{Dhcp4}{'client-classes'}[0]{'only-if-required'},
+    JSON::true,
+    'numeric additional-only intent is rendered as a JSON boolean'
+);
+
 my $empty_boot_json = $backend->render_dhcp4_config(
     {
         subnets => [