HP DL360 10 Gigabit Ethernet technology for industry-standard servers - Page 8

iSCSI protocol, such as a tape drive. The iSCSI stack at both ends of the path is used to encapsulate SCSI block commands into Ethernet Packets for transmission over IP networks as illustrated in Figure 3. Figure 3. iSCSI is SCSI over TCP/IP File System Disk Driver SCSI SCSI MP** iSCSI initiator File System Disk Driver SCSI iSCSI MP** TCP/IP Ethernet Direct attached block storage using SCSI/SAS* * Serial Attached SCSI ** Multipathing iSCSI target iSCSI SCSI TCP/IP Ethernet EEtthheerrnneett Remote block storage using iSCSI Initiators include software initiators and Host Bus Adapters (HBAs). Software initiators require CPU resources to manage the protocol stack. A more efficient approach is to offload the protocol management to an iSCSI HBA. The operating system sees an iSCSI HBA as a SCSI HBA. IP-based networks can drop data. To compensate for any dropped data, iSCSI maintains a buffer for the entire network bandwidth. This can increase the latency of the end-to-end round-trip transport and can require large buffers. Fibre Channel over Ethernet Fibre Channel over Ethernet (FCoE) is an emerging 10GbE fabric already embraced by some network hardware vendors. FCoE encapsulates Fibre Channel frames within the Ethernet fabric. FCoE uses the same Open Systems Interconnection (OSI) layer as IP networks. The following are some of the advantages that come with FCoE implementation: FCoE utilizes FC drivers, switches, and other infrastructure Existing FC security and management applications are unchanged FCoE provides a 10Gigabit Ethernet fabric with potentially no data loss, compared to IP based networks Existing SAN management tools can be used to access storage FCoE can utilize enhanced Ethernet features like traffic priority and flow control 8