System Overview - Juniper PTX5000 Hardware Manual

• Always-on infrastructure base—The PTX5000 is engineered with full hardware redundancy for
cooling, power, Routing Engines, Control Boards, and Switch Interface Boards (SIBs), allowing service
providers to meet stringent service-level agreements across the core.
• Nondisruptive software upgrades—The PTX5000 features a resilient operating system that supports
high availability (HA) features such as graceful Routing Engine switchover (GRES), nonstop active
routing (NSR), and unified in-service software upgrade (unified ISSU), providing software upgrades
and changes without disrupting network traffic.

System Overview

The PTX5000 occupies 36 rack units (36 U) and accommodates up to eight Flexible PIC Concentrators
(FPCs), each of which can be configured with two Physical Interface Cards (PICs) to support a variety of
network media types.
The system architecture of the PTX5000 cleanly separates control operations from packet forwarding
operations. This design eliminates processing and traffic bottlenecks, permitting the PTX5000 to achieve
high performance.
• Control operations are performed by the host subsystem, which runs the Junos operating system
(Junos OS) to handle routing protocols, traffic engineering, policy, policing, monitoring, and
configuration management.
• Forwarding operations are performed by the Packet Forwarding Engines, which consist of hardware,
including ASICs, designed by Juniper Networks. The ASICs are a definitive part of the hardware
design and enable the PTX5000 to achieve data forwarding rates that match current fiber-optic
capacity. For the forwarding capacity of each supported FPC type, see
PTX5000" on page 147.
"FPCs Supported on the
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