LAN Span^™ - Local Area Network Bridge

Table of Contents

Because LAN users are not just local anymore, LAN managers must also be concerned about wide area networking issues. Now, the LAN manager must worry about whether traffic is from building to building, across the country or around the world. The best solution to the wide area complexities of modern local area networks is to rely on an experienced wide area networking vendor-Infotron-to provide remote LAN bridging solutions.

Infotron's LAN Span^™ can tie geographically separated LANs together into a unified network. LAN Span is compatible with any Version 2 Ethernet or 802.3 LAN and is completely independent of the layer 3 protocol. LAN Span is also compatible with a variety of wide area interfaces and provides the management capability to effectively control and monitor traffic on all parts of the network. Because Infotron provides only complete, integrated networks—and not just 'box' products—you get the benefit of total end-to-end solutions, service and support.

Table of Contents: Communications Cost Savings Interface Flexibility Network Management and Control Flexible Architecture Easy Operation Advanced Network Integration Technical Specifications Only From Infotron

Communications Cost Savings

LAN Span connects remotely located Ethernet or 802.3 LANs over high-speed synchronous wide area networks (WANs). LAN Span is protocol-transparent because it works at the data link layer independently of high-level protocols that operate over the LANs (such as DECnet, XNS or TCP/IP). So it allows all attached stations to communicate over the same WAN.

This independence is combined with one of the most powerful feature sets available for LAN bridges. Proprietary hardware allows filtering rates of 15,000 frames/second, while the software allows filter customizing to match your application needs. Because the filtering algorithms only forward traffic that is actually destined for the remote LAN rather than 'flooding' links, LAN Span can actually reduce required link speeds, and therefore communication costs.

Interface Flexibility

The choice of WAN link interfaces available for LAN Span includes V.35, RS-449, T1 and CCITT G.732, with speeds ranging from 9.6 kbps to 2.048 Mbps. This link interface flexibility allows LAN Span to operate in a diversity of point-to-point or star network applications, including leased lines, satellite links, microwave links and switched lines. Also, cabling to other Infotron networking products is available to make building total solutions easier.

LAN Span maximizes WAN bandwidth usage and minimizes delay by filtering out messages that should not be forwarded across the WAN. These include messages destined for a LAN device that is not located at the remote LAN, messages with CRC or framing errors, messages with inadequate forwarding rights and message collisions. Message filtering saves you money by letting you choose a WAN with a capacity that's not way beyond your specific needs.

Network Management and Control

Your single VT100 or VT220 terminal (or compatible) attaches to LAN Span to provide all the key management and control functions in a menu-driven, easy-to-use format. From your console, you can perform a wide range of tasks.

For example, you can key in operating parameters for the LAN or WAN interface or load them from an internal disk drive; view live, on-line statistical information; receive current or stored event reports; perform diagnostic testing; and access the console port at the remote LAN Span unit via a dial-up connection. Two levels of console security are provided for up to 20 console users.

LAN Span maintains extensive statistics regarding transmit and receive frame traffic, including frames sent, frames dropped and why, such as frame errors, network violations, port or system congestion and incorrect rights. The statistics are continuously updated on the console screen or are printed at specific report intervals.

Flexible Architecture

LAN Span boasts a unique, high-performance architecture that provides easier maintenance and expandability plus higher throughput than its primary competitors. It is built to handle the needs of corporate networks that are destined to grow.

The design is completely modular, and all internal modules are easily replaced if a failure occurs. Because LAN Span is designed with an open architecture with room to expand, you will be able to add all future enhancements as LAN Span develops from a small networking device to a full member of Infotron's StreamLineTM networking family with the capability to interconnect many LANs across multiple WANs.

The bus-based architecture connects the various controller, memory and processor boards and is rated at a throughput of 40 Mbps. This ensures minimal degradation under high traffic volumes of such key performance parameters as filtered frames/second and forwarded frames/second.

LAN Span lets you arrange your LANs in a star-like configuration.

You can connect your LANs over your network backbone.

Use this approach when LAN traffic alone cannot justify a 1.544/2.048 Mbps link.

Easy Operation

LAN Span is a "plug-and-play" box, so your job is easier. After you install a LAN Span unit into each of your two LANs (as you would any other LAN device), put in the intervening WAN link and power up; LAN Span takes over and you're running.

Right away, LAN Span starts listening to the activity on the local LAN. By monitoring this information, source and multicast address tables are created and down-line loaded to the remote LAN Span. After this initial learning period, messages are forwarded across the WAN.

The post-learn update feature allows local and remote tables to be updated with new addresses so new users can also perform inter-LAN communications. And the local address table aging feature helps to keep the tables lean and efficient. More secure networks can be set to store new addresses only and subsequently add these addresses to the tables at the discretion of the operator.

Newly learned addresses are assigned default forwarding rights. Forwarding rights let you specify whether a LAN device can forward information to another LAN device (physical rights), to a group of LAN devices (multicast rights) or to all other LAN devices (broadcast rights). You can assign separate rights to each stored address.

Advanced Network Integration

LAN Span fits within the framework of Infotron's Advanced Network Integration (ANI), the unifying concept behind the entire family of Infotron wide area networking products. ANI ensures that our products work together and grow with your network.

Infotron's goal is to provide integrated network solutions, and LAN Span is ideally suited for applications with Infotron's StreamLine products and Infostream NX4600/NX3200/NX3000 high-speed network exchanges. With these products, you can merge your voice and data requirements under a single network management scheme.

However, LAN Span does not require you to integrate with just Infotron products; any high-speed multiplexer or networking switch may be used. The LAN Span bridge may also be used by itself in point-to-point applications.

Technical Specifications:

Only From Infotron

Infotron provides total integrated data and voice networking solutions. With our wide range of quality products, we can build a communications network that meets your needs today but still performs in tomorrow's environment. Since your needs include many of today's technologies, our solutions address them all, whether they are 1.544/2.048 Mbps, ISDN, T3 (45 Mbps) or LAN.

Five key attributes are built into each of our products and make each one uniquely Infotron: connectivity, compliance with worldwide communications standards, integrated network management, a total networking approach to solving customer problems and a service and support organization second to none in the industry.

Built by people with more than two decades of networking experience, LAN Span is a part of an integrated network solution that has a focus on the future. If LANs are part of your future, give us a call.