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Adapter Card Aggregation

The number and variety of PCI Express native-mode devices

is growing quickly. As these devices become mainstream, it

will be necessary to create multi-function and multi-port

adapter cards with PCI Express capability.

The PEX 8509 can be used to create an adapter or mezzanine

card that aggregates the PCI Express devices into a single port

that can be plugged into a backplane or a motherboard. Figure

3 shows the PEX 8509 in this application.

Figure 3. Aggregation Adapter Card

Control Plane Application

The PEX 8509 is ideal for migrating existing PCI control

planes in routers to high-speed PCI Express interface to meet

increased packet processing needs. Figure 4 shows a controller

card with a PEX 8509 connecting the Control Processor to as

many as seven line cards each via a x1 port. This usage model

provides connectivity to multiple line cards giving the

processor control over a large number of line cards in mid-

range routers.

Figure 4. Control Plane

Control Planes For Larger Systems

For larger systems that need more than 8 ports, two PEX 8509

devices can be linked together to provide up to 14 ports.

Figure 5 shows such an application. The two PEX 8509

devices together provide connectivity for up to 13 line cards

each via an x1 link. The Control Processor connected to a

PEX 8509 via an x1 port on the controller card in this example

can control up to 13 different line cards.

Figure 5. Control Plane for Large Systems

Redundant Control Plane Applications

For those systems that need redundant control planes, the

PEX 8509 can be used in conjunction with the PEX 8508

which supports Non-Transparent bridging. With the NT port,

the PEX 8508 can connect to a redundant control card

providing fail-over support. An added benefit of the PEX 8509

& PEX 8508 combination design is the increased fan-out

capability – it is now possible to connect a total of 9 line cards

to the controller card.

Figure 6. Redundant Control Plane

GE

GE

GE

1

1

4

1

1

GE

PEX 8509

MAC/PHY

MAC/PHY

MAC/PHY

MAC/PHY

GE

GE

GE

1

1

4

1

1

GE

PEX 8509

PEX 8509

MAC/PHY

MAC/PHY

MAC/PHY

MAC/PHY

Line Card 1

Line Card 7

Controller Card

Controller Card

Co-Processor-

Security/DSP

Local

Processor

NPU/ASIC

Framer

PHY

Control

Processor

Memory

PEX 8509

Switch

Up to 7 x1

cards

Line Card 1

Line Card 7

Controller Card

Controller Card

Co-Processor-

Security/DSP

Local

Processor

NPU/ASIC

Framer

PHY

Control

Processor

Memory

PEX 8509

PEX 8509

Switch

Switch

Up to 7 x1

cards

Control

Processor

Memory

PEX 8508

PEX 8509

Controller Card

Control

Processor

Memory

PEX 8508

Port #1

Redundant

Control Card

NTB

PEX 8509

Port #9

To Line Cards

To Line Cards

LC #9

LC #1

Switch

Switch

Switch

Switch

Fabric Card

GE Ports

to Fabric

Control

Processor

Memory

PEX 8508

PEX 8508

PEX 8509

PEX 8509

Controller Card

Control

Processor

Memory

PEX 8508

PEX 8508

Port #1

Redundant

Control Card

NTB

PEX 8509

PEX 8509

Port #9

To Line Cards

To Line Cards

LC #9

LC #1

Switch

Switch

Switch

Switch

Switch

Switch

Switch

Switch

Fabric Card

GE Ports

to Fabric

Controller Card

Controller Card

Control

Processor

Memory

PEX 8509

To Line Cards

PEX 8509

7 ports

6 ports

Controller Card

Controller Card

Control

Processor

Memory

PEX 8509

PEX 8509

To Line Cards

PEX 8509

PEX 8509

7 ports

6 ports