Use the Statistics tab to monitor the reception
of individual data streams. The MAC address, the
packet ID code (PID), and the transmission speed
in kb/s are displayed for each stream. Unicast, broadcast,
or multicast are indicated for each stream as well as whether or not the
PID is active.

Data Streams
To receive data from an Internet/data channel,
the tuner tunes to specific streams of packeted digital information. Each stream
is identified by a code called a packet ID code, or PID. The digital
receiver uses PID filters and MAC Address filters to select desired streams.
There are three types of Internet Protocol packet streams received by the digital
receiver card:
- A unicast stream is a single stream meant
to be received by the single user (receiver) who requested it. The difference
between unicast and broadcast is the difference between receiving a personal
letter and listening to public radio: one is uniquely addressed; the other
isn't. The reason why you can view a web page on the Internet while the person
next to you is viewing an entirely different web page is because your web
page is addressed to you, while his or her web page is addressed to him/her:
each person is receives a different, uniquely addressed, unicast stream. A
media access control address (MAC address) is a numerical code used
to address the information in a unicast stream.
- A multicast stream is one stream to be
received by multiple users simultaneously. An example might be a concert being
multicast over the Internet to fans worldwide. In multicast, rather than transmitting
separately addressed unicast streams for each user, the multicast sent from
the Internet to your network travels most of the distance as a single stream.
At the latest possible instant the stream splits to reach the multiple users.
- A broadcast stream is a transmission
meant to be received indiscriminately by all users. When a conventional radio
stations "broadcasts" a signal, the signal blankets every antenna
in the area of the radio station: it does not take a specific addressed path.
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