Intel® IXF1104 4-Port Gigabit Ethernet Media Access Controller

5.2.3Pre-Pending Function

The IXF1104 MAC implements a pre-pending feature to allow 1518-byte Ethernet packets to be pre-padded with two additional bytes of data so that the packet becomes low-word aligned. The

2-byte pre-pend value is all zeros and is inserted before the destination address of the packet being pre-pended. This value is fixed and cannot be changed.

This function is enabled by writing the appropriate data to the “RX FIFO Padding and CRC Strip Enable ($0x5B3)" for each port.

A standard 1518-byte Ethernet packet occupies 379 long words (four bytes) with two additional bytes left over (1518/4 = 379.5). To eliminate the memory-management problems for a network processor or switch fabric, the two remaining bytes are dealt with by the addition of two bytes to the start of a packet. This results in a standard 1518-byte Ethernet packet received by the IXF1104 MAC being forwarded to the higher-layer device as a 380-long-word packet. The upper-layer device is responsible for stripping the additional two bytes.

This feature was added to the IXF1104 MAC to assist in the design of higher-layer memory management. The addition of the two extra bytes is not the default operation of the IXF1104 MAC and must be enabled by the user. The default operation of the IXF1104 MAC SPI3 receive interface forwards data exactly as it is received by the IXF1104 MAC line interface.

5.3Gigabit Media Independent Interface (GMII)

The IXF1104 MAC supports a subset of the GMII interface standard as defined in IEEE 802.3 2000 Edition for 1 Gbps operation only. This subset is limited to operation at 1000 Mbps full- duplex.

The GMII Interface operates as a source synchronous interface only and does not accept a TXC clock provided by a PHY device when operating at 10/100 Mbps speeds.

Note: The RGMII interface must be used for applications that require 10/100/1000 Mbps operation.

The IXF1104 MAC does NOT support 10/100 Mbps copper PHY devices that are implemented using the MII Interface.

Note: MII operation is not supported by the IXF1104 MAC.

The user can select GMII, RGMII, or Optical Module/SerDes functionality on a per-port basis. This mode of operation is controlled through a configuration register.

While IEEE 802.3 specifies 3.3 V operation of GMII devices, most PHYs use 2.5 V signaling. The IXF1104 MAC provides a 2.5 V drive and is 3.3 V-tolerant on inputs.

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Datasheet

Document Number: 278757

Revision Number: 009

Revision Date: 27-Oct-2005

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Intel IXF1104 manual Gigabit Media Independent Interface Gmii, Pre-Pending Function
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IXF1104 specifications

The Intel IXF1104 is a cutting-edge Network Interface Controller (NIC) designed to meet the needs of high-speed communication in modern networking environments. As the demand for bandwidth-intensive applications continues to grow, Intel's IXF1104 is engineered to deliver exceptional performance, reliability, and scalability, making it an ideal choice for data centers and enterprise networks.

One of the main features of the IXF1104 is its support for high-speed Ethernet connectivity, providing up to 100 Gbps throughput. This capability allows organizations to handle large amounts of data traffic efficiently, accommodating everything from cloud computing to big data analytics. The NIC utilizes advanced packet processing technology which ensures minimal latency, enhancing the overall user experience.

The IXF1104 is built on a robust architecture that integrates Intel's latest processing technologies. It incorporates a multi-core processing engine that allows for parallel processing of network packets, improving the handling of simultaneous network requests. This architecture also supports offloading features, freeing up CPU resources for other critical tasks, which optimizes system performance.

In terms of technologies, the IXF1104 supports a variety of standards including Ethernet and Fiber Channel, making it versatile across different networking environments. Its compatibility with industry-standard networking protocols ensures that it can easily integrate into existing frameworks, facilitating seamless upgrades and expansions.

Another significant characteristic of the IXF1104 is its energy efficiency. With Intel’s focus on sustainability, this NIC is designed to consume less power relative to its performance output, thereby reducing overall operational costs for organizations. It employs dynamic power management features that adjust power usage based on demand, which is especially beneficial in large-scale deployments.

Additionally, security features are woven into the IXF1104 design, protecting sensitive data from potential threats. Hardware-based security functions, including encryption capabilities and secure boot processes, ensure that the NIC can safeguard data integrity against unauthorized access.

Overall, the Intel IXF1104 stands out in the crowded NIC market by offering high-performance capabilities, energy efficiency, and robust security features. Its combination of advanced technologies and characteristics positions it as a strategic asset for modern networks, empowering organizations to achieve their connectivity and performance goals in an increasingly data-driven world.
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