Juniper PTX5000, Руководство по оборудованию

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• Processing of routing protocol packets—The Routing Engine handles all packets that concern routing
protocols, freeing the Packet Forwarding Engine to handle only packets that represent Internet
traffic.
• Software modularity—Because each software process is devoted to a different function and uses a
separate process space, the failure of one process has little or no effect on the others.
• In-depth Internet functionality—Each routing protocol is implemented with a complete set of Internet
features and provides full flexibility for advertising, filtering, and modifying routes. Routing policies
are set according to route parameters (for example, prefix, prefix lengths, and BGP attributes).
• Scalability—Junos OS routing tables have been designed to hold all the routes in current networks
with ample capacity for expansion. Additionally, Junos OS can efficiently support large numbers of
interfaces and virtual circuits.
• Management interface—Different levels of system management tools are provided, including the
Junos OS command-line interface (CLI), the Junos XML management protocol, the craft interface,
and SNMP.
• Storage and change management—Configuration files, system images, and microcode can be held and
maintained in primary and secondary storage systems, permitting local or remote upgrades.
• Monitoring efficiency and flexibility—The PTX5000 supports functions such as alarm handling and
packet counting on every port, without degrading packet-forwarding performance.
RE-DUO-C2600-16G Routing Engine Components
Each Routing Engine (shown in Figure 59 on page 119 ) consists of the following components:
• CPU—Runs Junos OS to maintain the routing tables and routing protocols.
• DRAM—Provides storage for the routing and forwarding tables and for other Routing Engine
processes.
• EEPROM—Stores the serial number of the Routing Engine.
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