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+Caching in HTTP
+===============
+
+ETAG
+----
+
+Res 200:
+
+    ETag: "fa6e-3e3073913b100"
+
+Req:
+
+    If-None-Match: "fa6e-3e3073913b100"
+
+Res 304:
+
+    ETag: "fa6e-3e3073913b100"
+
+
+LAST MODIFIED
+-------------
+
+Res 200:
+
+    Last-Modified: Mon, 28 Jan 2013 22:29:45 GMT
+
+Req:
+
+    If-Modified-Since: Mon, 28 Jan 2013 22:29:45 GMT
+
+Res 304:
+
+    Last-Modified:Mon, 28 Jan 2013 22:29:45 GMT
+
+
+EXPIRES
+-------
+
+Res 200:
+
+    Expires: Tue, 19 Mar 2013 11:17:57 GMT
+
+Do not try again before Tue, 19 Mar 2013 11:17:57 GMT
+
+CACHE-CONTROL
+-------------
+
+Res 200:
+
+    Cache-Control: max-age=300
+
+Do not try again until 5 minutes from now
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