diff --git a/youtube_dl/extractor/common.py b/youtube_dl/extractor/common.py
index 64fb869aab..e2d9f52b01 100644
--- a/youtube_dl/extractor/common.py
+++ b/youtube_dl/extractor/common.py
@@ -1310,6 +1310,7 @@ class InfoExtractor(object):
                 'url': manifest_url,
                 'manifest_url': manifest_url,
                 'ext': 'flv' if bootstrap_info is not None else None,
+                'protocol': 'f4m',
                 'tbr': tbr,
                 'width': width,
                 'height': height,