Functionality and Features: Broadcom NetXtreme II™ Network Adapter User Guide
Functional Description
The Broadcom NetXtreme IITM adapter is a new class of Gigabit Ethernet (GbE) converged network interface controller (C-NIC) that can simultaneously perform accelerated data networking, storage networking, and high-performance clustering on a standard Ethernet network. The C-NIC offers acceleration for all popular protocols used in the data center, such as:
- TCP Offload Engine (TOE) for accelerating TCP over 1 GbE, 2.5 GbE, and in the future, 10 GbE
- Internet Small Computer Systems Interface (iSCSI) offload for accelerating network storage access featuring centralized boot functionality (iSCSI boot)
- Remote Direct Memory Access (RDMA) offload for accelerating network clustering
NOTES:
- Separate licences are required for all offloading technologies.
- Offloading technologies are supported when the Broadcom NetXtreme II adapter is installed in a system with Windows Server 2003 with SNP.
- iSCSI and RDMA offload are currently not supported.
Enterprise networks that use multiple protocols and multiple network fabrics benefit from the C-NICs ability to combine data communications, storage, and clustering over a single Ethernet fabric by boosting server CPU processing performance and memory utilization while alleviating I/O bottlenecks.
The Broadcom NetXtreme II adapter includes a 10/100/1000-Mbps Ethernet MAC with both half-duplex and full-duplex capability and a 10/100/1000 copper PHY. The transceiver is fully compatible with the IEEE 802.3 standard for auto-negotiation of speed.
Using the Broadcom teaming software, you can split your network into virtual LANs (VLANs) as well as group multiple network adapters together into teams to provide network load balancing and fault tolerance functionality. See Configuring Teaming and Broadcom Gigabit Ethernet Teaming Services for detailed information about teaming. See Virtual LANs, for a description of VLANs. See Configuring Teaming for instructions on configuring teaming and creating VLANs on Windows operating systems.
Features
The following is a list of the Broadcom NetXtreme II adapter features:
- TCP Offload Engine (TOE)
- Internet Small Computer Systems Interface (iSCSI) offload
- Remote Direct Memory Access (RDMA) offload
- Single-chip solution
- Other performance features
- Manageability
- Broadcom Advanced Control Suite 2 diagnostic and configuration software suite
- Supports PXE 2.0 specification (Linux Red Hat PXE Server, Windows 2000 Server, Windows Server 2003, Intel APITEST, DOS UNDI, Rembo Technology Auto-Deploy Server)
- Wake on LAN support
- Universal Management Port (UMP) support
- Statistics for SNMP MIB II, Ethernet-like MIB, and Ethernet MIB (IEEE Std 802.3z, Clause 30)
- SMBus controller
- ACPI 1.1a compliant (multiple power modes)
- IPMI support
- Advanced network features
- Layer-2 Priority Encoding (IEEE 802.1p)
- High-speed on-chip RISC processor
- Up to 4 classes of service (CoS)
- Up to 4 send rings and receive rings
- Integrated 96 KB frame buffer memory
- GMII/MII Management Interface
- Four unique MAC unicast addresses
- Support for multicast addresses via 128 bits hashing hardware function
- Serial flash NVRAM memory
- JTAG support
- PCI Power Management Interface (v1.1)
- 64-bit BAR support
- EM64T processor support
- AMD-64 processor support
- 1.2 V core voltage, 0.13 µm process
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. Without the TCP Offload Engine, the TCP/IP protocol suite runs on the host CPU, consuming a very high percentage of its resources and leaving little resources for the applications. With the use of the Broadcom NetXtreme II adapter, the TCP/IP processing can be moved to hardware, freeing the CPU for more important tasks such as application processing.
The Broadcom NetXtreme II adapter's TOE functionality allows simultaneous operation of up to 1024 fully offloaded TCP connections. 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 Small Computer Systems Interface (SCSI) or iSCSI. SCSI is a popular protocol that enable systems to communicate with storage devices, using block-level transfer (i.e., address data stored on a storage device that is not a whole file). iSCSI maps the SCSI request/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 (i.e., 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.
NOTES: The iSCSI offload feature is not available for all Broadcom network adapters.
Remote Direct Memory Access (RDMA)
Remote DMA (RDMA) is a technology used to allow an application or a kernel program to communicate directly with a remote peer by moving data to/from local memory to the remote memory of another system. Direct transfer of data by the RDMA network interface card (RNIC), with no need for host CPU involvement in the data transfer (also known as kernel bypass), significantly reduces CPU utilization of data communication and drastically reduces latencies for moving data from one machine to the other. Reduced latency to the range of 1020 ms enables a broad range of high-end latency-sensitive applications to best perform over Ethernet. Applications like database, High-Performance Computing (HPC), and storage can now use an RNIC for very high performance.
NOTES: The RDMA offload feature is not available for all Broadcom network adapters.
Power Management
Adapter speed connection when the system is down waiting for a wake-up signal may be at 10 Mbps or 100 Mbps, but can return to 1000 Mbit/s when the system is up and running if connected to a 1000 Mbps capable switch. Systems intending to use Wake on LAN (WOL) should be connected to a switch capable of both 1000 and 10/100 Mbps speeds.
NOTES:
- For specific systems, see your system documentation for WOL support.
- WOL is supported in Broadcom NetXtreme II devices with silicon revisions of B2 or later. For more information, see Limitations.
Adaptive Interrupt Frequency
The adapter driver intelligently adjusts host interrupt frequency based on traffic conditions to increase overall application throughput. When traffic is light, the adapter driver interrupts the host for each received packet, minimizing latency. When traffic is heavy, the adapter issues one host interrupt for multiple, back-to-back incoming packets, preserving host CPU cycles.
ASIC with Embedded RISC Processor
The core control for Broadcom NetXtreme II adapters resides in a tightly integrated, high-performance ASIC. The ASIC includes a RISC processor. This functionality provides the flexibility to add new features to the card and adapts it to future network requirements through software downloads. This functionality also enables the adapter drivers to exploit the built-in host offload functions on the adapter as host operating systems are enhanced to take advantage of these functions.
Broadcom Advanced Control Suite 2
Broadcom Advanced Control Suite 2 (BACS2), a component of the Broadcom teaming software, is an integrated utility that provides useful information about each network adapter that is installed in your system. The BACS2 utility also enables you to perform detailed tests, diagnostics, and analyses on each adapter, as well as to modify property values and view traffic statistics for each adapter. BACS2 is used on Windows operating systems to configure teaming and to add VLANs.
Supported Operating Environments
The Broadcom Netxtreme II adapter has software support for the following operating systems:
Network Link and Activity Indication
For copper-wire Ethernet connections, the state of the network link and activity is indicated by the LEDs on the RJ-45 connector, as described in Table 1. For fiber optic Ethernet connections, the state of the network link and activity is indicated by a single LED located adjacent to the port connector, as described in Table 2. Broadcom Advanced Control Suite 2 also provides information about the status of the network link and activity (see Vital Sign).
Table 2. Network Link and Activity Indicated by the Port LED LED Appearance Network State Off No link (cable disconnected) Continuously illuminated Link Blinking Network activity