CMG-DCM
key-bucket
: the key-bucket code, which tells the DCM which key to use for
that particular stream.
The cryptographic hardware required to produce authenticated CD1.1 streams is
installed only in Authentication Modules (AMs). To transmit unauthenticated
CD1.1 data, you should use a key-bucket code of
-1
.
prefix
: A prefix used to determine where to place generated CD1.1
subframes. For example, a prefix of
/data/HPA1.
will produce files in the
/data/
directory beginning with
HPA1.
and followed by a unique timestamp.
Several streams may produce files using the same prefix; indeed, this is
recommended.
Blank lines, and any lines beginning with
#
, are ignored.
When you have finished editing the file, clicking Save changes will write the
changes to disk. The changes will not take effect, however, until the CD1.1
service is restarted. You can restart all running CD1.1 services by clicking
Restart CD1.1.
DSS
DSS (Data Subscription Service) is a packet format which enables data and
statistics to be requested from a seismic installation. A DSS server is designed
to handle many concurrent requests from clients with varying levels of
privilege, and may prioritize requests according to their origin and urgency.
Güralp Systems' data modules include a package,
libdss
, which is designed
to communicate with installations using DSS as either a server or a client. A
daemon utility,
dssserver
, is also available which receives requests on a
network port and replies to them. This server can be loaded onto Güralp DCM
and AM data modules as required.
The dssserver program
dssserver
initially listens on a network port for DSS_REG registration
packets from clients. Any incoming connnections other than DSS_REG are
refused with a DSS_REF packet. Receiving a valid DSS_REG packet, dssserver
sends a DSS_ACK packet and adds the client to an internal client list, identified
by its source IP address and port number.
Once a client is registered,
dssserver
will accept other DSS command
packets from it.
dssserver
fulfils requests by following this procedure:
•
Receiving a valid DSS_REQ packet,
dssserver
will send a
DSS_ACK packet immediately and add the request to an internal
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Issue A
