diff -Nru simplestreams-0.1.0-491-g2920b06/debian/changelog simplestreams-0.1.0-492-g4403b3d/debian/changelog
--- simplestreams-0.1.0-491-g2920b06/debian/changelog	2020-04-06 21:47:23.000000000 +0000
+++ simplestreams-0.1.0-492-g4403b3d/debian/changelog	2020-04-08 19:19:50.000000000 +0000
@@ -1,6 +1,6 @@
-simplestreams (0.1.0-491-g2920b06-0ubuntu1~ubuntu19.04.1) disco; urgency=low
+simplestreams (0.1.0-492-g4403b3d-0ubuntu1~ubuntu19.04.1) disco; urgency=low
 
   * Auto build.
 
- -- Launchpad Package Builder <noreply@launchpad.net>  Mon, 06 Apr 2020 21:47:23 +0000
+ -- Launchpad Package Builder <noreply@launchpad.net>  Wed, 08 Apr 2020 19:19:50 +0000
 
diff -Nru simplestreams-0.1.0-491-g2920b06/debian/git-build-recipe.manifest simplestreams-0.1.0-492-g4403b3d/debian/git-build-recipe.manifest
--- simplestreams-0.1.0-491-g2920b06/debian/git-build-recipe.manifest	2020-04-06 21:47:23.000000000 +0000
+++ simplestreams-0.1.0-492-g4403b3d/debian/git-build-recipe.manifest	2020-04-08 19:19:50.000000000 +0000
@@ -1,2 +1,2 @@
-# git-build-recipe format 0.4 deb-version 0.1.0-491-g2920b06-0ubuntu1
-lp:simplestreams git-commit:2920b068f32becc833d197aa5fb7b65cb0b5b178
+# git-build-recipe format 0.4 deb-version 0.1.0-492-g4403b3d-0ubuntu1
+lp:simplestreams git-commit:4403b3df81ad3e00908579c33ef4dacc3942ae41
diff -Nru simplestreams-0.1.0-491-g2920b06/doc/README simplestreams-0.1.0-492-g4403b3d/doc/README
--- simplestreams-0.1.0-491-g2920b06/doc/README	2020-04-06 21:47:23.000000000 +0000
+++ simplestreams-0.1.0-492-g4403b3d/doc/README	2020-04-08 19:19:50.000000000 +0000
@@ -114,6 +114,15 @@
     'path' entries for a given item must be immutable.  That is, for a
     given 'path' under a mirror, the content must never change.
 
+    An 'item' dictionary may contain a 'mirrors' element.
+
+    'mirrors' entries it used for supply a list of mirrors prefix where
+    retrieve the item. When 'mirrors' is present client must create
+    the URL of the resource to fetch with the 'path' entry:
+
+    item_url = item_mirrors[0] . item_path
+
+
 == Index ==
 This is a index of products files that are available.
 It has a top level 'index' dictionary.  Each entry in that dictionary is a
diff -Nru simplestreams-0.1.0-491-g2920b06/simplestreams/generate_simplestreams.py simplestreams-0.1.0-492-g4403b3d/simplestreams/generate_simplestreams.py
--- simplestreams-0.1.0-491-g2920b06/simplestreams/generate_simplestreams.py	2020-04-06 21:47:23.000000000 +0000
+++ simplestreams-0.1.0-492-g4403b3d/simplestreams/generate_simplestreams.py	2020-04-08 19:19:50.000000000 +0000
@@ -91,7 +91,10 @@
     for content_id in trees:
         if condense:
             util.products_condense(trees[content_id],
-                                   sticky=['path', 'sha256', 'md5', 'size'])
+                                   sticky=[
+                                       'path', 'sha256', 'md5',
+                                       'size', 'mirrors'
+                                   ])
         content = trees[content_id]
         to_write.append((index['index'][content_id]['path'], content,))
     out_filenames = []
diff -Nru simplestreams-0.1.0-491-g2920b06/tests/unittests/test_generate_simplestreams.py simplestreams-0.1.0-492-g4403b3d/tests/unittests/test_generate_simplestreams.py
--- simplestreams-0.1.0-491-g2920b06/tests/unittests/test_generate_simplestreams.py	2020-04-06 21:47:23.000000000 +0000
+++ simplestreams-0.1.0-492-g4403b3d/tests/unittests/test_generate_simplestreams.py	2020-04-08 19:19:50.000000000 +0000
@@ -264,3 +264,19 @@
                 'item-1': {'arch': 'amd64'},
                 'item-2': {'arch': 'amd64'}, }}}}}}
         self.assertEqual(bar, expected)
+
+    def test_mirrors(self):
+        trees = {
+            'bar': {'products': {'prodbar': {'versions': {'1': {'items': {
+                'item-1': {'arch': 'amd64', 'mirrors': ['url1', 'url2']},
+                'item-2': {'arch': 'amd64'}}}}}}}}
+        with temp_dir() as out_dir, patch('sys.stderr', StringIO()):
+            write_streams(out_dir, trees, self.updated, FakeNamer,
+                          condense=False)
+            with open(os.path.join(out_dir, 'bar.json')) as bar_file:
+                bar = json.load(bar_file)
+        expected = {
+            'products': {'prodbar': {'versions': {'1': {'items': {
+                'item-1': {'arch': 'amd64', 'mirrors': ['url1', 'url2']},
+                'item-2': {'arch': 'amd64'}, }}}}}}
+        self.assertEqual(bar, expected)
diff -Nru simplestreams-0.1.0-491-g2920b06/tools/make-test-data simplestreams-0.1.0-492-g4403b3d/tools/make-test-data
--- simplestreams-0.1.0-491-g2920b06/tools/make-test-data	2020-04-06 21:47:23.000000000 +0000
+++ simplestreams-0.1.0-492-g4403b3d/tools/make-test-data	2020-04-08 19:19:50.000000000 +0000
@@ -53,7 +53,13 @@
 
 FAKE_DATA = {
     'root.tar.gz': {'size': 10240},
-    'root.tar.xz': {'size': 10241},
+    'root.tar.xz': {
+        'size': 10241,
+        'mirrors': [
+            'https://us.images.linuxcontainers.org/',
+            'https://uk.images.linuxcontainers.org/'
+        ]
+    },
     'root.manifest': {'size': 10242},
     'lxd.tar.xz': {'size': 10245},
     'tar.gz': {'size': 11264},
@@ -311,6 +317,8 @@
                 rootitem = item.copy()
                 rootitem['ftype'] = extension.lstrip('-.')
                 rootitem['path'] = rootpath
+                if 'mirrors' in FAKE_DATA[ftype]:
+                    rootitem['mirrors'] = FAKE_DATA[ftype]['mirrors']
                 create_fake_file(prefix, rootitem)
 
             # and sha256 hash the combined file