PEX 8716, PCI Express Gen 3 Switch, 16 Lanes, 4 Ports

© PLX Technology, www.plxtech.com

Page 4 of 5

10/7/2010, Version 1.0

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Backup

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Error Injection & SerDes Loopback

Using the PEX 8716’s Error Injection feature, users can

inject malformed packets and/or fatal errors into their

system and evaluate a system’s ability to detect and

recover from such errors. The PEX 8716 also supports

Internal Tx, External Tx, Recovered Clock, and Recovered

Data Loopback modes.

Applications

Suitable for host-centric as well as peer-to-peer traffic

patterns, the PEX 8716 can be configured for a wide

variety of form factors and applications.

Host Centric Fan-out

The PEX 8716, with its symmetric or asymmetric lane

configuration capability, allows user-specific tuning to a

variety of host-centric applications. Figure 6 shows a

server design where the PEX 8716 is being used to fan-out

to endpoints and PCI Express slots. Since the PEX 8716 is

compliant with PCIe Gen 1 and Gen 2 devices, the PEX

8716 can also be used to bridge Gen 1 and Gen 2

endpoints to Gen 3 chipsets and processors (and vice

versa).

Memory

CPU

CPU

CPU

CPU

x4s

x4

x1s

SATA

Endpoint

PCIe Gen1, Gen2, or Gen3 slots

x8

PEX 8716

PCI

PCH

Figure 6. Host Centric Fan-Out

Network Interface Cards

The PEX 8716 can also be utilized in communications

applications such as Network Interface Cards (NICs).

NICs, like the one shown in Figure 7, can utilize the PEX

8716 for its fan-out capabilities. In the example below, the

PEX 8716 is being used on a Dual-port 10-Gigabit

Ethernet (GE) NIC card. The PEX 8716 utilizes a x8 link

to connect to the host and two x4 downstream links to fan-

out to the 10GE ports. The peer-to-peer communication

feature of the PEX 8716 allows the endpoints to

communicate with each other without any intervention or

management by the host.

10 GE

10 GE

MAC/PHY

MAC/PHY

x8

x4

x4

Dual-Port NIC

PEX 8716

Figure 7. 10GE NIC Fan-Out

Host Bus Adapters

The PEX 8716 is well suited for Host Bus Adapter cards

(HBAs) as well. Figure 8 shows a Quad-Port Fibre

Channel HBA utilizing the PEX 8716 to allow

connectivity to two Fibre Channel (FC) controllers. The

PEX 8716 uses a x8 link on the upstream port and two x4

downstream links to fan-out to the FC controllers. Each FC

controller supports two FC ports.

x8

x4

x4

Quad-Port FC HBA

PEX 8716

FC

FC

FC Cont.

FC

FC

FC Cont.

Figure 8. Quad-Port Fibre-Channel HBA

Fail-Over in Storage Systems with Multicast

The PEX 8716’s Multicast feature can be used to

simultaneously send redundant packets to a backup system

(Figure 9). In the example below, using Multicast (yellow

lines), the CPU sends data to its endpoints as well as to a

backup system

(via an NT port)

in one t

as opposed to

having to se

multiple

transactio

each endpoint.

By offloading th

task of backing

up data onto the

secondary

system, pro

and syste

performance is

enhance

Figure 9. Failover Sy

ransaction

nd

ns to

e

cessor

m

d.

stems