Issue No. 22
PEX 8508 Key Features
♦
8-lane PCI Express switch
♦
Up to five configurable ports
(x1, x2, x4)
♦
Low latency: under 150ns
♦
Integrated SerDes
♦
Quality-of-Service with up to 2
Virtual Channels/port
♦
Selectable Non-Transparent
Bridge Port
♦
Peer-to-peer switching and host
centric data transfer
♦
19mmx19mm, 296 pin PBGA
Application:
Fan-out in Network Security Appliances
PLX Product:
Key Benefit:
PEX 8508 – 8-lane PCI Express Switch
Five configurable PCIe Ports
Network Security Appliances Incorporating
PCIe Switches for Expanded Services
Networks with dedicated enterprise level security appliances such as
Web Application Firewalls as shown in figure 1 are becoming more
prevalent. They sit in-line between WAN access routers and firewalls
and internal LAN networks and provide security far beyond those of
basic Firewall/VPN solutions. These new systems allow dynamic
threat detection and protection from application layer hacker intrusions
and mutating virus, worms and other malicious traffic. But in order to
minimize added latency, provide wire-speed throughput, support SSL
encrypted traffic, provide compression and caching, WAN link
optimization and other
benefits, these integrated
systems need multiple
dedicated processing
boards. PCIe switches are
used to interconnect these
boards and the controller.
Figure 1
PEX 8508 Other Features
♦
Standards Compliant-Exceeds
PCIe base specification r1.1
♦
Non-blocking Switch Fabric
with full line rates
♦
End-to-end CRC and Poison bit
support
♦
Standard r1.1 compliant Hot-
Plug Controllers with Hot Plug
on all ports
♦
Basic and Advanced error
reporting
♦
Dual clocking domain support
with simultaneous SSC and
constant frequency clocking
♦
Hardware fixed and Round
Robin packet queue arbitration
♦
Vaux, Wake#, & Beacon
♦
Configuration through I2C,
host or optional EEPROM
♦
JTAG boundary scan-AC/DC
♦
All Link & device power
management states including
D3 (cold)
♦
Lane and polarity reversal
♦
Typical Power: 2.5 Watts
The PEX 8508 Supports Economical Fan-out
The PEX 8508 is an inexpensive 5-port/8-lane PCI Express switch
with a host of capabilities applicable to security appliances. These
switches provide numerous configuration options including a one x4
port and four x1 ports. These switches support aggregation traffic from
upstream to/from downstream ports as well as peer-to-peer data
transfers with no host intervention. Ingress to egress throughput
latency is under 150 ns which is critical for these data path oriented
products. System error management and control is supported through
Advanced Error Reporting and data integrity is enhanced through
optional ECRC. Non-transparency support allows host and
processing board microprocessor domain isolation.
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November 2005, ExApp22_8508_Security_Apps.doc