Communications access

From the communications standpoint, SIOM is designed to make access to the market as easy as possible for the different agents participating in same.

Depending on the specific needs of each agent, SIOM allows them to select one communication medium or another, modifying the system response speed but always ensuring that the application behaves in the same way from the functional standpoint. Agents may have alternative channels for communicating with the system; these are protected against eventual failure of the default communication procedure. In any case, and in order to ensure system availability, all input points are duplicated on SIOM, thus guaranteeing the maintenance of communications in the event of simple faults in any access channels or equipment.

With this approach, SIOM allows agents to communicate using the following means:

Internet Connection

SIOM includes two Internet connection lines. All agents may access the market by means of a simple Internet communication through an Internet provider. In this case access speed depends mainly on the agent’s connection to the network through the provider and on the behaviour of the network itself. Given its low cost, this is the main procedure used by agents representing a small-average number of bid units to access the market. There are no special requirements (except the requirements relating to market access via the Internet).

Connection by ISDN Equipment

SIOM includes two independent banks of IDSN input equipment. All agents with the necessary equipment and an ISDN data line may access the market by simply calling the two head end numbers of both banks. Access speed is almost 64Kbps. This procedure can be used by agents representing a high-average number of bid units who require a fast connection but without incurring in the cost of a dedicated connection line. It may be useful as an emergency procedure for agents with digital lines or as a normal procedure for agents who require more speed in order to exchange information. In order to be able to connect by ISDN, agents must notify the Market Operator accordingly using the corresponding request form. Once the connection has been authorised, and after performing the relevant tests, communication can be established when the agent wishes.

Connection by Dedicated Line

SIOM offers agents the option of contracting up to two dedicated end-to-end communication lines (entering along independent paths) between their installations and the Market Operator. Once both ends have been configured, access to the market is direct.
Access speed depends on the type of line contracted. This procedure can be used by agents representing a large number of bid units wishing to contract a permanent connection with the market that provides them with important features. It is recommended that this connection be accompanied by some of the options described previously to provide coverage for any communications failures that may occur. In order to be able to connect to SIOM using a dedicated line, agents must notify the Market Operator using the corresponding request form. Once authorised, the connection lines will be installed and configured. The agents will be able to access the market using this channel as soon as the connection is up and running and after performing the relevant tests.

SIOM-SIOME systems configuration

The SIOM system architecture has been designed as a three layer structure, from the hardware point of view:

  • Access network, where all the communications equipments allow connections to market participants (via the different access types, ie. Internet, ISDN, leased lines), system operator, emergency system SIOME, etc.
  • Web network, where the web servers are located for both navigator access or web services access.
  • Data base network, where the storage equipment resides (data base and files).

Between each layer there exist security equipments (firewalls) to manage and control the connections between services located in different layers and therefore, protecting undesired accesses to services or information.

The image besides shows a general overview of the SIOM system:


All the equipments have been designed to minimize downtime and redundancy is required at each layer, providing uninterrupted operation in case one of the redundant equipment fails.

Similarly to the local redundancy of SIOM equipments, OMEL also has in place an emergency system called SIOME, geographically separated from the main system SIOM. The emergency system SIOME is similar in structure and functionality to the main system SIOM, providing the same services to the market participants in case a disaster occurs at the main site.

The emergency system SIOME has all the necessary data replicated from the main system SIOM, by means of real time data synchronization between sites and should a disaster occurs at the main site, the uninterrupted operation of the electricity market could be managed from SIOME following the standard emergency procedures in place.

Although not all the equipments in the emergency system SIOME have redundancy, the most important ones are also duplicated guaranteeing continuous operation in case of a single failure.

The image besides shows a general overview of the SIOM-SIOME systems configuration:


All this points set SIOM system a high availavility and fault tolerant system.