Cisco Systems RJ-45-to-AUX manual 100Mbps, STS−3c/STM−1 155Mbps, 184

FDDI	100Mbps
STS−3c/STM−1	155Mbps
TAXI 4B/5B	100Mbps

LightStream 1010

The LS1010, shown in Figure 9.2, is the most recent addition to the LightStream series of ATM switches used for multiservice applications. The switch has a five−slot, modular chassis with two fault−tolerant, load−sharing power supplies. The switch contains a central slot that is dedicated to a single, field−replaceable switch processor module. The switch processor module supports 5Gbps of shared memory that is fully non−blocking. Non−blocking means the switch fabric can process and switch just as much or more data than all the ports on the switch combined can possibly bring in. This is possible because the switch uses a feature card and a high−performance reduced instruction set computer (RISC) processor that provides the speed and routing intelligence for the architecture.

Figure 9.2: The LS1010 switch.

The RISC processor provides traffic management mechanisms that allow for bursty data traffic and QoS for such data as voice, video, multimedia, and other applications that require guaranteed bandwidth. The LS1010 can buffer up to 65,536 cells in its on−board shared buffers; this buffering minimizes the possibility of cell loss. Policies and scheduling with user−definable thresholds permit flexible support of multiple service classes.

The LS1010 family’s architecture is flexible. The switch architecture is scalable and can support WAN interfaces with speeds ranging from a T1 to an OC−12. The LS1010 supports many traffic classes, such as those listed in Table 9.2.

Table 9.2: Traffic classes supported on the LightStream 1010.

Traffic Class	Designation
Constant bit rate (CBR)	Used for telephony, legacy, and site−to−site
	videoconferencing applications.
Real−time variable	Used for time−delay or jitter−sensitive applications
	such as those used for videoconferencing at the
	desktop level.
Variable bit rate (VBR)	Comes in two forms: real time (VBR−RT) and non
	real time (VBR−NRT). These forms are used in
	high−delay, high−jitter−tolerant, and high−bandwidth
	applications, including many video broadcasts.
Available bit rate (ABR) + minimum cell rate (MCR)	Used in the WAN. This class provides best−effort
	delivery with congestion feedback notification.
	Optionally, you can define a minimum bandwidth
	requirement.
Unspecified bit rate (UBR)	Used by many legacy data applications. This class
	provides best−effort delivery.

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