System Architecture Design

pSHIELDSystem Architecture DesignPUEthernet and Gigabit EthernetAnother alternative in LAN communication, concerning Power node in our case, is Ethernet or IEEE 802.3standard. It is a frame-based networking technique, defining a number of wiring standards for the PhysicalLayer and an addressing format and MAC procedures for the Data Link Layer. Some technicalspecifications, are shortly presented below (including the amendment of Gigabit Ethernet IEEE 802.3-2008):• Medium accessCSMA/CD• Data rate Gigabit links may operate Full Duplex (Fast Ethernet Switch) or HalfDuplex (Fast Ethernet Hub)• Hardware ComponentsHubs, Switches, Routers Media converters (change twisted pair copper wires to fiber optic cabling)6.2.5 InterfacesDuring the incremental presentation of pSHIELD reference system architecture, we defined a genericinterface NS (Network Services), responsible for Network Layer services provision. It is an integralelement of all node types in the architecture hierarchy (L-ESD → pS-ESD → pS-SPD-ESD) and managestheir Network Layer communication and functionalities. The innovative SPD functionalities implemented inpSHIELD introduced functional blocks and subsystems (e.g. Network Adapter) interoperate with Legacysystems through network interface NS.There is also interface pS-NS, conveying all the needed information to the pSHIELD Middleware adapter,in order for the SPD composability of the Network layer legacy and Network pSHIELD-specificfunctionalities to be enabled.A more detailed registration of all layer interfaces of pSHIELD, can be found in § 6.6.-6.7.6.2.6 Security6.2.6.1 Cryprographic AlgorithmsAccording to the ISO/IEC 27002 information security standard, the objective of network security is thepreservation of three principles:• Confidentiality: the communication data are only disclosed to authorized subjects• Integrity: the data in the communication retain their veracity and are not able to be modified byunauthorized subjects• Availability: authorized subjects are granted timely access and sufficient bandwidth to access thedataPUD2.3.2Issue 5 Page 99 of 122