CMG-EAM

Enhanced Acquisition Module

A stand-alone EAM

The CMG-EAM is a versatile and powerful module designed for receiving, recording and transmitting data captured using Güralp Systems Limited’s range of seismic measuring equipment.

About the EAM

The CMG-EAM is the successor to the CMG-DCM, with a more flexible and powerful hardware platform and Güralp System’s next generation Platinum firmware. The CMG-EAM is recommended for all new installations. Platinum firmware can be installed on existing CMG-DCMs and this is recommended for all redeployments - see this page for more details.

The CMG-EAM is 100% plug-compatible with the CMG-DCM and retains all of its functionality, enabling rapid integration into existing installations.

Backed by the stability of the Linux operating system, but still consuming less than 1 W of power, the CMG-EAM is an ideal choice for seismic installations ranging from single-instrument boxes to the largest arrays.

The CMG-EAM is designed to integrate seamlessly with computer networks and the Internet. An on-board web server allows you to log in to the EAM by secure HTTPS and alter its configuration. You can also use it to configure any attached Güralp digitizer modules or digital sensors from anywhere on the Internet.

In addition, the CMG-EAM can work with many popular data formats and protocols including CD1.0/1.1, full SEED, SeedLink and of course Güralp’s own Scream! software.

The EAM supports a wide range of data transfer methods.

CMG-EAM units can be integrated with any new CMG-DM24 digitizer, and can also be retrofitted onto existing units to enhance their communication abilities. Comprehensive configuration options allow the unit to be installed with ease into a pre-existing array. Multiple CMG-EAM units can communicate with each other using the highly efficient GDI-link protocol, allowing you to construct robust arrays with redundant links - complete with link monitoring, automatic fail-over and recovery.

The CMG-EAM’s unique flexibilty derives from its custom-designed hardware platform, the underlying Linux operating system and Güralp Systems’ Platinum firmware. This firmware is also available as a field-upgrade for existing CMG-DCMs - see this page for more details.

Features

Remote configuration and monitoring over the web (secure https protocol)
User-level access and security
Configure and control attached digitisers and digital sensors over the network
Support for PPP over RS232
Low power consumption (<1 W)
Full TCP/IP support
Linux Operating System
Flash memory storage
Easy-access onboard hard disk (surface units)
Optional built-in UPS

Web page interface

Direct configuration and data monitoring.

Stored data can be downloaded direct from the web server.

Comprehensive networking options.

A flexible and innovative feature of the CMG-EAM is its on-board web server, which can be configured and accessed securely from your network or from anywhere on the Internet.

Using the web server, users can administer the entire seismic system, including monitoring data, checking tamper lines and reconfiguring EAM services.

The web page also provides full access to the configuration settings of the Güralp digitizers and digital instruments attached to it. Using this facility, a logged-in user can alter the settings of a remote installation from anywhere on the network.

Form factors

Depending on your site requirements, the EAM may be supplied in several formats. Although these look different, they all share the same internal features.

Stand-alone

The standard EAM module is housed in a high-impact copolymer polypropylene case with mil-spec connectors. It may be installed in a ground station or other location remote from the digitiser and seismometer.

It can accept data from up to three devices connected to it through RS232 ports.

A stand-alone EAM comes equipped with a rugged 40Gb USB/IEEE1394 ("FireWire") hard disk for on-site storage. The hard disk is hot-swappable and can be removed with gloves; its unique journalled file system is robust yet readable with standard PC, Linux and SunOS drivers (USB Mass Storage/FAT-32).

Rack-mounted

The CMG-NAM

The functionality of an EAM can also be supplied on a conventional computing platform in a form factor suitable for mounting in a standard 19” rack. In this configuration, it is known as a CMG-NAM (Network Acquisition Module) and is available with a wide variety of extra physical networking adapters and storage options, including managed RAID arrays.

Integrated

An integrated borehole EAM

An integrated EAM may be combined with a digitiser and seismometer to produce a single borehole instrument capable of measuring seismic data, storing, and passing it on over a network.

These EAMs use a single 26-pin connector to communicate, rather than having separate ports.

Connectivity options

EAMs in any of these forms may be supplied in the configuration most suitable to your requirements, depending on how you wish to connect it to your network.

Using the 10BaseT Ethernet network option, you can connect the EAM to any TCP/IP network, and communicate with it using a web-based interface. You can also log in to the EAM’s Linux operating system directly using SSH, or read data from any application that supports the GCF format (such as Scream!, Antelope, or Earthworm).
Alternatively, an internal or external modem may be supplied, through which you can use a dial-up or other communications link to connect to your home network.
As a third option, an 802.11b Wi-Fi module may be installed.

Whichever options you choose, you can also use any free RS232 port to connect the EAM to a single computer for local monitoring and configuration, or through it to a wider network using PPP. A dedicated RS232 console port under the lid also allows all external RS232 ports to be used for connecting to devices and networks.

CMG-AM Authentication Module

The CMG-AM is based on the same low power technology as the CMG-EAM, but with additional strong cryptographic capabilities. Using an on-board crypto-token, the CMG-AM is capable of signing outgoing data at source.

The CMG-AM is particularly powerful in borehole installations, as it can be combined with the digitizer in a single downhole package. Data exiting the borehole is already cryptographically signed, making it practically impossible to interfere with the data between production and transmission.