Web GUI Monitoring & Control
4.7.3.6.4
Bit Rate
The bit rate field indicates the estimated bit rate of the stream being processed. When the
demodulator is configured for ACM/VCM, then the rate displayed is currently incorrect; the
correct bit rate may be obtained by scaling the displayed rate by the ratio between the symbol
rate and the maximum symbol rate (45 M baud). In this case, the scaling factor to be applied is
13.5/45.0, or 30%.
4.7.3.6.5
Errored Second Rate (ESR)
The Errored Second Rate is a measure of the number of one second intervals that have been
affected by an uncorrected transmission error in the preceding time window (see***).
4.7.3.6.6
Severely Errored Second Rate (SESR)
The Severely Errored Second Rate is a measure of the number of one second intervals that have
been affected by many transmission errors (>30% of received blocks) in the preceding time
window (see ***).
4.7.3.6.7
Background Block Error Rate (BBER)
The Background Block Error Rate is a measure of the rate of un-correctable base-band blocks,
averaged over the preceding time window (see ***). Severely Errored Seconds are discounted
from this computation.
4.8
SBD75e: BISS Decryption
Basic Interoperable Scrambling System (BISS) is a satellite signal scrambling system developed by
the European Broadcasting Union and a consortium of hardware manufacturers.
When using BISS the transmission is protected by a 12 digit "session word" that is agreed by the
transmitting and receiving parties prior to transmission. The key is entered into both the encoder
and decoder, this key then forms part of the encryption of the digital TV signal and only receivers
with the correct key will decrypt the signal.
The rapid increase in the use of Digital Satellite News Gathering (DSNG) technology resulted in
the availability of digital codec equipment from a number of vendors. At the same time, the
absence of standard methods for the securing and scrambling of DSNG broadcasts spawned
the development of several different proprietary security mechanisms. The widespread
acceptance of DVB standards made it possible to propose and provide a security mechanism
that offered interoperability between the equipment of different DSNG vendors. This enabled
broadcasters to combine equipment from several vendors, while making systems more future-
proof.
BISS is based on the DVB-CSA specification, and the use of fixed clear keys called Session Words
(SWs). BISS specification Mode 1 is used for DSNG. BISS specification Mode E (BISS with Encrypted
keys – referred to as BISS-E) introduces an additional mechanism to accept the insertion of
Encrypted Session Words (ESWs) while, at the same time, conserving interoperability. This
mechanism is backward compatible with BISS specification Mode 1.
The BISS option will appear on the tabs if the feature key is installed and may be viewed by
selecting the BISS tab. A window similar to the shown in Figure 4.20 is displayed. The BISS window
can be split into 3. The top is for selecting the BISS mode, the middle is a status view and the
bottom is an application for generating Encrypted Session words.
4-22
SBD75e Series Demodulator Installation and Operation Manual