to 16 times consecutively, after which the station reports a transmission error to the higher layer protocol. The probability of a collision occurring is directly proportional to the number of stations, frequency of transmissions, size of frames, and length of the LAN segment.

Under the 802.3 specifications, no station can monopolize the network by sending more data than is allowed. Occasionally, a misbehaving application or a faulty adapter may transmit more data than is allowed. This gives rise to a condition called jabber. Jabber refers to the transmission of a packet whose length is greater than 1518 octets. Where repeaters are used to extend the Ethernet LAN, jabber can also occur when the transceiver that is attached to the repeater has Signal Quality Error (SQE) set to on.

7.1.2 Frame Size

In the Ethernet LAN environment, all data transmission must occur using Ethernet or IEEE 802.3 frame formats. For details on Ethernet and IEEE 802.3 frame formats, please refer to LAN Concepts and Products, GG24-3178-03.

IEEE 802.3 and Ethernet specify a minimum frame size (header plus data) of 64 octets while the largest frame is 1518 octets. A packet whose frame size is less than 64 octets is called an undersized packet or a runt and oversized packet refers to a packet whose frame size exceeds 1518 octets.

7.1.3 Data Integrity

To ensure integrity of the data being transmitted, each data frame is appended with Frame Check Sequence (FCS) information. The FCS information is computed by the transmitting station using a cyclic redundancy algorithm executed against the contents of the data frame to be sent. The same algorithm is used by the receiving station to recompute the FCS on the data frame received.

A Cyclic Redundancy Checksum (CRC) Alignment Error will be reported by the receiving station when there is a mismatch between the receiver-computed FCS and the senders FCS.

7.1.4 Ethernet Addressing Mode

In Ethernet, there are three types of addressing modes:

Direct addressing

In the direct addressing mode, the sender station has to know the Ethernet address of the receiver station before communication can occur.

Broadcast

Broadcast addresses a frame to all stations in the network. It uses a special code in the destination address field. When a broadcast is transmitted, it is received and processed by every station in the network.

Multicast

Multicast addresses a frame to a subset of stations in the network. It uses a special group address to allow multiple stations to listen to a single address. When a frame is sent to a group address, all stations subscribing to that group will receive it.

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IBM 8260 manual Frame Size, Data Integrity, Ethernet Addressing Mode

8260 specifications

The IBM 8260 is a significant entry in the realm of enterprise servers, recognized for its performance, scalability, and robust features designed to cater to demanding business environments. It primarily serves as a high-capacity server for large organizations, capable of handling extensive workloads and complex applications without compromising speed or efficiency.

One of the standout features of the IBM 8260 is its powerful processing capabilities. It typically comes equipped with multiple processor units based on the IBM POWER architecture, which is renowned for its high-performance computing. This architecture allows the server to execute numerous simultaneous tasks, making it ideal for environments that require multitasking and high throughput.

Memory capacity is another key characteristic of the IBM 8260. Depending on the specific configuration, it can support substantial amounts of RAM, ensuring that applications can run effectively without the bottlenecks often associated with data-intensive tasks. This is crucial for enterprises that rely on real-time data analytics, large database management, and resource-heavy applications.

In terms of storage, the IBM 8260 offers flexible options. It supports a variety of storage solutions, including solid-state drives (SSDs) and traditional hard drives, catering to different performance and capacity needs. This scalability in storage helps organizations manage their data effectively while ensuring quick access and retrieval times.

Connectivity is also a prominent feature of the IBM 8260. The server includes advanced networking capabilities, supporting various protocols and technologies that facilitate fast data transfer and communication between devices. This enhances overall network performance, essential for businesses that depend on cloud computing and distributed computing environments.

Additionally, the IBM 8260 is designed with a focus on reliability and availability. It incorporates redundant components, such as power supplies and cooling systems, minimizing the risk of downtime. This is critically important for enterprises that require continuous availability of services.

The server’s management features are also noteworthy. IBM provides a suite of management tools that allow IT administrators to monitor performance, configure hardware settings, and troubleshoot issues seamlessly. This ease of management is bolstered by automation capabilities, enabling organizations to enhance operational efficiency.

In conclusion, the IBM 8260 stands out in the competitive server landscape due to its high processing power, extensive memory and storage options, advanced connectivity, reliability features, and robust management tools. Such attributes make it a viable choice for organizations seeking to enhance their IT infrastructure and streamline their operations effectively.