Using the SEHI100TX Hub View

Multicast Packets

The number of multicast packets received by this device, module, or port since the window was last opened or reset. Multicast packets are simultaneously addressed to more than one address, but fewer than all addresses.

Collisions

The number of collisions recorded by this device, module, or port since the window was last opened or reset. The SEHI100TX counts both receive collisions

Ñthose detected while a port is receiving data Ñ and transmit collisions Ñ those detected while a port is transmitting data (i.e., the port has transmitted one of the colliding packets); however, these counts are combined and a single total value is displayed. Collisions of this type (called ÒlegalÓ collisions, as opposed to the OOW collisions described below) are a natural by-product of a busy network; if you are experiencing high numbers of collisions, it may be time to redirect network trafÞc by using bridges or routers. Extremely high collision rates can also indicate a data loop (redundant connections) or a hardware problem (some station transmitting without listening Þrst).

Total Errors

The number of errors of all types recorded by this device, module, or port since the window was last opened or reset.

Alignment Errors

The number of misaligned packets recorded since the window was last opened or reset. Misaligned packets are those which contain any unit of bits which is less than a byte Ñ in other words, any group of bits fewer than 8. Misaligned packets can result from a packet formation problem, or from some cabling problem that is corrupting or losing data; they can also result from packets passing through more than two cascaded multi-port transceivers (a network design which does not meet accepted Ethernet spec).

CRC Errors

CRC, or Cyclic Redundancy Check, errors occur when packets are somehow damaged in transit. When each packet is transmitted, the transmitting device computes a frame check sequence (FCS) value based on the contents of the packet, and appends that value to the packet. The receiving station performs the same computation; if the FCS values differ, the packet is assumed to have been corrupted and is counted as a CRC error. CRC errors can result from a hardware problem causing an inaccurate computation of the FCS value, or from some other transmission problem that has garbled the original data. The CRC error counter shows the total number of CRC errors recorded since the window was last opened or reset.

OOW Collisions

The number of out-of-window collisions recorded since the window was last opened or reset. OOW collisions occur when a station receives a collision signal while still transmitting, but more than 51.2 sec (the maximum Ethernet propagation delay) after the transmission began. There are two conditions which can cause this type of error: either the networkÕs physical length exceeds IEEE

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Monitoring Hub Performance

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Cabletron Systems SEHI100TX-22 manual Multicast Packets, Total Errors, Alignment Errors, CRC Errors, OOW Collisions

SEHI100TX-22 specifications

Cabletron Systems SEHI100TX-22 is a high-performance network interface card that has been designed for reliable data transfer in various networking environments. Ideal for both enterprise and small business applications, the SEHI100TX-22 delivers exceptional performance at a competitive price point.

One of the standout features of the SEHI100TX-22 is its support for 100Base-TX Ethernet standards, which enables high-speed data transmission at rates of up to 100 Mbps. This high throughput capacity makes it an excellent choice for organizations that require swift and efficient data handling, particularly in environments with heavy network traffic.

The card is equipped with two RJ-45 connectors, allowing it to support dual-port configurations. This dual-port setup enhances networking capabilities by enabling fault tolerance and load balancing, ensuring that the network remains operational even in the event of a failure. Moreover, it supports full-duplex operation, allowing for simultaneous bi-directional data transmission, further improving overall network efficiency and performance.

Another significant advantage of the SEHI100TX-22 is its compatibility with a wide range of operating systems and platforms, including Windows, Linux, and various UNIX variants. This versatility ensures that it can be seamlessly integrated into existing network infrastructures without the need for extensive configuration or modification.

In terms of installation and maintenance, the SEHI100TX-22 is user-friendly, thanks to its Plug and Play capability. This feature allows for easy installation; users can simply insert the card into an available PCI slot, and the operating system will automatically recognize and configure the device, minimizing downtime and simplifying the setup process.

Additionally, the SEHI100TX-22 incorporates advanced technologies like Auto-Negotiation, which automatically detects the speed and duplex capabilities of the connected device, thus optimizing the network performance. The card also features various onboard diagnostic LEDs, providing real-time feedback on connection status and data activity, which aids in troubleshooting and performance monitoring.

In summary, the Cabletron Systems SEHI100TX-22 offers a robust set of features that cater to the demands of modern network environments. With its high-speed capabilities, dual-port support, compatibility across multiple operating systems, and user-friendly installation process, it remains a solid choice for organizations looking to enhance their networking performance and reliability.