FDDI Applications

In most instances, the IEEE 802.3/Ethernet frame format is translated automatically into the appropriately corresponding FDDI frame format. Ethernet

802.2frames are translated to FDDI 802.2 frames; Ethernet II frames are translated to FDDI SNAP frames; non-AppleTalk Ethernet SNAP frames are translated to FDDI SNAP frames; and AppleTalk Ethernet SNAP frames are translated to FDDI SNAP frames (AppleTalk format).

However, because Ethernet Raw frames do not have a Type or Length Þeld, and canÕt be automatically translated onto an FDDI network, you must select the appropriate translation method to an FDDI frame format (for transmitting to FDDI stations or for bridging back to an Ethernet network).

If the frame is exiting the FDDI ring through another FDDI/Ethernet bridge, the FDDI frame must be converted back into an IEEE 802.3/Ethernet frame. As there are four potential Ethernet frame types to which the two FDDI frame types can be translated, you must determine which translation options you want in effect Ñ depending on which network protocols and applications are being run on the destination network.

In addition, there are frame size differences between FDDI (which allows a maximum frame size of 4500 bytes) and Ethernet frames (1518 byte maximum, excluding preamble), so FDDI frames may need to be fragmented before being bridged onto an Ethernet network.

The Frame Translation window lets you set the parameters for frame translation and fragmentation when Ethernet trafÞc needs to traverse an FDDI ring. The frame types that you select for translation will depend on which higher-layer communications protocols and software you are running on the network segments connected to your Ethernet-to-FDDI bridge. Each frame type and its usage is described below.

Ethernet Frames

The HSIM-F6 supports translation of the following four Ethernet frame types:

Ethernet II

Ethernet II is the Novell NetWare designation for the basic Ethernet frame type (also commonly referred to as Ethernet or Ethernet DIX). This frame format has an Ethernet II MAC header with a two byte Ethernet Type Þeld. The Type Þeld contains a protocol ID which indicates the upper layer protocol (e.g., XNS, DECnet, TCP/IP, etc.) used in the Data Þeld of the packet. Most current transmission protocols, including TCP/IP, use the Ethernet II frame format, as do networks running AppleÕs AppleTalk 1 protocol and DigitalÕs DECnet protocol.

Note that the Type Þeld of an Ethernet II frame will always have a decimal value greater than 1500, so that it can be differentiated from the Length Þeld of Ethernet 802.2 frames (described below).

Configuring FDDI Frame Translation Settings

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Cabletron Systems 2000 manual Ethernet Frames

2000 specifications

Cabletron Systems was a prominent company in the networking and communications industry during the late 20th century, and by the year 2000, it had established itself as a leader in providing high-performance networking solutions. The company was known for its innovative approach to network architecture and its commitment to delivering reliable products that enabled seamless connectivity in various environments.

One of the primary features of Cabletron Systems in 2000 was its advanced networking technologies, including Local Area Network (LAN) and Wide Area Network (WAN) solutions. The company specialized in developing multi-layer switches that could efficiently manage traffic and deliver high-speed data transfer. Their products were particularly popular in enterprise settings, where network performance and reliability were paramount.

Cabletron's solutions included a range of products, from Ethernet switches to routers, which were designed with scalability and flexibility in mind. This allowed businesses to adapt their networks to accommodate growth, without the need for a complete overhaul of their infrastructure. The company’s Integrated Networking Architecture (INA) was a significant innovation during this period, enabling efficient communication and management of diverse network resources.

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Security was also a key feature of Cabletron’s offerings in 2000. With growing concerns about data breaches and unauthorized access, the company incorporated advanced security measures into its products. These features included robust authentication protocols, encryption options, and secure management interfaces, which helped safeguard sensitive data during transmission.

Customer support and service were paramount to Cabletron Systems' business model. The company provided extensive resources, including training and technical support, to ensure that customers could maximize the potential of their networking solutions. This dedication to customer satisfaction contributed significantly to Cabletron’s reputation in the marketplace.

In summary, Cabletron Systems in 2000 emerged as a frontrunner in the networking industry, characterized by its innovative technologies, commitment to interoperability, emphasis on security, and strong customer support. Their products and solutions were designed to empower businesses, helping them achieve greater efficiency, scalability, and reliability in their network operations.