Operation

ATM Cell Traffic Flow in the 9A656-04

The 9A656-04 SmartSwitch utilizes several innovative features that result in a completely redundant, fault-tolerant design. The three most important hardware facets of the 9A656-04 SmartSwitchÕs features are the Cell Transfer Matrix, Cabletron Systems ASICs, and the i960 HD RISC Processor.

Cell Transfer Matrix (CTM)

The Cell Transfer Matrix provides a Time Division Multiplexed (TDM) based mesh of full duplex, high-speed (1.6 Gbps) interconnections that carry standard ATM cell trafÞc. These interconnections are in fact a series of point-to-point links between an individual module and every other module in the chassis. Each 9A656-04 has 14 physical CTM interfaces; one connection to every other 9A656-04 along with a local loopback interface. A SmartSwitch 9500 chassis with 14 9A656- 04 modules installed would have 182 point-to-point links between all the interface modules. This enables the SmartSwitch 9500 to provide an aggregate switching capacity of 63 Gbps if 14 modules are connected to the CTM backplane.

NOTE

The interconnections exist only between modules that are directly attached to the CTM.

Cabletron Systems ASICs

The 9A656-04 SmartSwitch utilizes Þve separate Cabletron Systems designed ASICs to perform switching functions. Refer to Figure 3-1to see how these Þve ASICs work together to provide proper trafÞc ßow. The deÞnitions for these ASICs are as follows:

Queue ASIC

The 9A656-04 has four Queue ASICs installed on the motherboard. These ASICs support 16 priority queues each. The Queue ASICs support all classes of ATM service including Constant Bit Rate (CBR), Variable Bit Rate (VBR), Available Bit Rate (ABR) and UnspeciÞed Bit Rate (UBR). The Queue ASICs also manage all cell transfers to the Utopia ASICs, using a weighted round-robin algorithm.

TDM (Time Division Multiplexer) ASIC

The TDM ASIC is the central switching engine of the 9A656-04. The TDM ASIC maintains the connections table, gathers statistics, and provides Usage Parameter Control (UPC) policing. The TDM ASIC supports up to 128k virtual connections.

SARI (Segmentation and Reassembly Interface) ASIC

The SARI ASIC is the interface that controls the data ßow between the TDM Bus and the i960 Host Processor. The SARI ASIC has a 768-cell queue and provides the trafÞc management features of the 9A656-04.

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Cabletron Systems 9A656-04 ATM Module manual ATM Cell Traffic Flow in the 9A656-04, Cell Transfer Matrix CTM
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9A656-04 ATM Module specifications

The Cabletron Systems 9A656-04 ATM Module is a high-performance network device designed specifically for Asynchronous Transfer Mode (ATM) networking. This module is a part of Cabletron's extensive range of network equipment, which is known for its reliability and advanced technology, making it suitable for both enterprise and service provider environments.

One of the main features of the 9A656-04 module is its ability to support high-speed data transfer rates, accommodating the increasing bandwidth demands of modern networks. Operating at speeds of up to 155 Mbps, this module is ideal for applications that require rapid and efficient data exchange, such as multimedia streaming, video conferencing, and large file transfers.

The 9A656-04 employs a Cell-Switching architecture inherent to ATM technology. This architecture enables the module to efficiently handle multiple types of data traffic. The fixed-size cells used in ATM networking ensure low latency and predictable response times, which are essential for time-sensitive applications. By having dedicated bandwidth for voice, video, and data, the module provides a seamless networking experience.

Another key characteristic of the 9A656-04 is its scalability. Organizations can easily upgrade or expand their networks without experiencing significant downtime or requiring extensive reconfiguration. This modularity allows businesses to accommodate future growth and changing demands efficiently.

In terms of technologies, the Cabletron 9A656-04 module also supports a range of networking protocols, ensuring compatibility with existing infrastructure. This flexibility enables integration with various systems, making it a versatile solution in mixed networking environments.

The module is equipped with multiple interfaces, allowing for connection to various ATM devices and networks. This multiprotocol capability is a significant advantage as it enables organizations to utilize their existing networks while transitioning to ATM technology.

Furthermore, the 9A656-04 is built with advanced quality-of-service (QoS) features, ensuring that critical applications receive the necessary bandwidth and service level priority. This capability is vital in environments where different types of traffic intersect, allowing for optimal performance and user experience.

In conclusion, the Cabletron Systems 9A656-04 ATM Module is a robust and feature-rich solution for organizations looking to leverage the advantages of ATM technology. With its high-speed performance, scalable design, versatile protocol support, and reliable quality-of-service features, it addresses a range of networking needs, ensuring that businesses can operate efficiently in an increasingly digital world.
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