continuing merge from jesup, several minor fixes
diff --git a/doc/intro.txt b/doc/intro.txt
index aa8435c..37f9bd1 100644
--- a/doc/intro.txt
+++ b/doc/intro.txt
@@ -372,5 +372,24 @@
}
@endverbatim
+@section ISMAcryp ISMA Encryption Support
+
+The Internet Streaming Media Alliance (ISMA) specifies a way
+to pre-encrypt a media file prior to streaming. This method
+is an alternative to SRTP encryption, which is potentially
+useful when a particular media file will be streamed
+multiple times. The specification is available online
+at http://www.isma.tv/specreq.nsf/SpecRequest.
+
+libSRTP provides the encryption and decryption functions needed for ISMAcryp
+in the library @t libaesicm.a, which is included in the default
+Makefile target. This library is used by the MPEG4IP project; see
+http://mpeg4ip.sourceforge.net/.
+
+Note that ISMAcryp does not provide authentication for
+RTP nor RTCP, nor confidentiality for RTCP.
+ISMAcryp RECOMMENDS the use of SRTP message authentication for ISMAcryp
+streams while using ISMAcryp encryption to protect the media itself.
+
*/