System Architecture Design

pSHIELDSystem Architecture DesignPUThe Reconfigurability Engine is in charge to identify the optimal configuration of the pSHIELD NetworkLayer according to a given goal (e.g., the SPD metrics provided by the pSHIELD Middleware), theperceived radio environment (provided by the Representation Engine) and the acquired experience(provided by the Learning Engine). As an example, given a specific radio context, the ReconfigurabilityEngine can be able to derive a new, optimal Network Layer configuration to establish a communicationwith an already active Embedded System Device by using its preferred transmission standard, carrierfrequency and transmission power. This task is also known as Opportunistic Communication and allowsidentifying and exploiting an “opportunity” to establish a communication with the other players in a givencontext according to the surrounding environment conditions and the SPD goals.6.2.3.3 Node Performance Network ServicesNetwork services intended to increase SPD system level, through the effective administration andconfiguration of the nodes included, are listed below (the services concern mainly Power nodes and theisparticipation in LANs):• Remote configuration• SNMP of BIOS and FPGA A group of administrative computers manage the network devices• Remote self-test and performance monitoring• Privacy, authorization and authentication services6.2.4 Communication protocolsA reference to the communication technologies used by pSHIELD nodes is made at this point:802.15.4IEEE 802.15.4, the basis for ZigBee, is a standard which specifies the physical and MAC layers forWireless Personal Area Networks (WPANs), designed to be rather frugal in its functional power demands.In pSHIELD the standard could serve the communication needs of small to medium range sensors andadditionally of Legacy devices that potentially will complement a pSHIELD system environment. Micronode, for example, operates at 2.4 GHz based on 802.15.4 radio, with chip ChipCon TI CC2420. The RFtransceiver offers compliant medium access control and physical interfaces for data rates up to 250 kbps.The 802.15.4 radio includes a DSSS (digital direct sequence spread spectrum) baseband modemproviding a spreading gain (e.g. 9 dB in IRIS motes). The 2.4 GHz is divided into a number of channels,with a fixed width and spacing (e.g. the XM2110’s Atmel radio can be tuned 16 channels from 11 (2.405GHz) to 26 (2.480 GHz) each separated by 5 MHz.IEEE 802.11Alternatively most of the commercial sensors, legacy or belonging to pSHIELD hardware equipment, canhave IEEE 802.11 as their radio interface. Being the basis of Wi-Fi (and colloquially known with thisname), is probably the most popular family of standards for WLANs. Therefore in the framework ofpSHIELD, seems as a candidate technology for the communication of Power node. It is IP based, issuedin a set of amendments, the most known of which are summarized below:PUD2.3.2Issue 5 Page 97 of 122