Juniper EX4200 Series, Руководство по оборудованию, Страница: 26 / 344

Additionally, a 24-port model provides 100Base-FX/1000Base-X SFP ports. This model
is typically used as a small distribution switch.
All EX4200 switches have dedicated 64-Gbps Virtual Chassis ports (VCPs) that enable
you to connect the switches to each other. You can also use optional uplink module ports
to connect members of a Virtual Chassis across multiple wiring closets.
To provide carrier-class reliability, EX4200 switches include:
•
Dual redundant power supplies that are field-replaceable and hot-swappable. An
optional additional connection to an external power source is also available.
• A field-replaceable fan tray with three fans. The switch remains operational if a single
fan fails.
•
Redundant Routing Engines in a Virtual Chassis configuration. This redundancy enables
graceful Routing Engine switchover (GRES) and nonstop active routing (NSR).
• Junos OS with its modular design that enables failed system processes to gracefully
restart.
EX4200 switches have these features:
•
Run under Junos OS for EX Series switches
•
Have options of 24-port and 48-port models
• Have options of full (all ports) PoE/PoE+ capability or partial (8 ports) PoE capability
• Have optional uplink modules that provide connection to distribution switches
Uplink Modules
Optional uplink modules are available for all EX4200 switches. Uplink modules provide
two ports for installing 10-gigabit small form-factor pluggable (XFP) transceivers, four
ports for installing 1-gigabit small form-factor pluggable (SFP) transceivers, two ports
for installing 10-gigabit small form-factor pluggable (SFP+) transceivers. You can use
XFP, SFP, or SFP+ ports to connect an access switch to a distribution switch or to
interconnect member switches of a Virtual Chassis across multiple wiring closets.
EX4200 switches also support an SFP+ Media Access Control Security (MACsec) uplink
module starting in Junos OS Release 13.2X50-D10. The SFP+ MACsec module provides
four MACsec-capable ports and can be configured to support up to four 1-gigabit SFP
transceivers or up to two 10-gigabit small form-factor pluggable (SFP+) transceivers.
Power over Ethernet Ports
PoE ports provide electrical current to devices through the network cables so that separate
power cords for devices such as IP phones, wireless access points, and security cameras
are unnecessary.
PoE was first defined in the IEEE 802.3af standard. Starting with Junos OS Release 11.1,
EX4200 switches support enhanced PoE, a Juniper Networks extension to the IEEE
302.3af PoE standard that increases the amount of power per PoE port. A later standard,
Copyright © 2015, Juniper Networks, Inc. 4
EX4200 Switch Hardware Guide