AT-2973SX, AT-2973T, AT-2973T/4, and AT-VNC10S Adapters Installation and User’s Guide
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Smart Load Balancing Teaming
IEEE Std 802.3ad teaming
TCP Offload Engine (TOE) The TCP/IP protocol suite is used to provide transport services for a wide
range of applications for the Internet, LAN, and for file transfer. The TCP
protocol is specifically designed to insure that data packets are delivered
error free and in the correct sequence from an application running a one
computer to the receiving application. The TCP protocol suite historically
has run on the host CPU, but with higher data rates, this consumes a very
high percentage of its resources while leaving little resources for the
applications. With the use of the Broadcom NetXtreme II adapter and the
TCP Offload Engine feature, the TCP/IP processing can be moved to
hardware, freeing the CPU for application processing and other higher
priority tasks.
The Broadcom NetXtreme II adapter's TOE functionality allows
simultaneous operation of up to 1024 fully offloaded TCP connections for
1-Gbps network adapters. The TOE support on the adapter significantly
reduces the host CPU utilization while preserving the implementation of
the operating system stack.
Internet Small Computer Systems Interface (iSCSI) The IETF has standardized the Internet Small Computer Systems
Interface (iSCSI). SCSI is a popular protocol that enables systems to
communicate with storage devices, using block-level transfer (that is,
address data stored on a storage device that is not a whole file). In
addition, iSCSI maps the SCSI request and response application protocols
and its standardized command set over TCP/IP networks.
As iSCSI utilizes TCP as its sole transport protocol, it greatly benefits from
hardware acceleration of the TCP processing (that is, use of a TOE).
However, iSCSI as a Layer 5 protocol has additional mechanisms beyond
the TCP layer. iSCSI processing can also be offloaded, thereby reducing
CPU utilization even further.
The Broadcom NetXtreme II adapter targets best-system performance,
maintains system flexibility to changes, and supports current and future
OS convergence and integration. Therefore, the adapter's iSCSI offload
architecture is unique as evident by the split between hardware and host
processing.
Power Management When the system is down and waiting for a wake-up signal, the adapter
speed connection may be at 10 Mbps or 100 Mbps. However, it can return
to 1000 Mbps when the system is up and running if it is connected to a
1000 Mbps capable switch. For this reason, connect systems that use the
Wake on LAN (WOL) feature to a switch capable of both 1000 and 10/100
Mbps speeds.