Juniper Networks EX9251 Ethernet Switch
Compact, evolved core for business agility and cloud.

Architecture and Key Components:

The EX9250 line delivers a number of common architectural elements across its campus distribution and core Ethernet switches. The REs employed by these switches run Junos OS, which processes all L2 and L3 protocols and manages the chassis. The EX9251 switch and the EX9253 line cards include Packet Forwarding Engines (PFEs) that process network traffic.

The EX9251 is designed for small enterprise campus deployments. The switch's shallow depth makes it ideal for wiring closets and distribution facilities. To maintain uninterrupted operation, redundant variable-speed fans cool the system, as well as the RE and PFE. Redundant hot-swappable power supplies convert building power to the internal voltage required by the system.

The EX9253 is designed for medium-sized enterprises, with efficient multicast replication handling and deep buffering to ensure performance at scale. To maintain uninterrupted operation, trays with redundant, variable-speed fans cool the line cards, RE, and PFE. The EX9253 power supplies convert building power to the internal voltage required by the system. All EX9253 components are hot-swappable, and all central functions are available in redundant configurations, providing high operational availability and ensuring continuous system operation during maintenance or repairs.

Junos Fusion Enterprise

Junos Fusion Enterprise technology enables a large number of devices deployed throughout a building to be managed as a single, logical device, reducing network complexity, simplifying network management, and lowering operational costs. Using Junos Fusion Enterprise, network administrators can connect up to 128 EX4300, EX3400, or EX2300 Ethernet access switches to one or two EX9250 Ethernet switches serving as aggregation platforms, creating a high port-density device that appears to the larger network as a single switch. In a Junos Fusion Enterprise deployment, the EX9250 aggregation switches serve as the single point of management that runs Junos OS and is responsible for configuring, monitoring, and maintaining all devices in the topology (see Figure 1).

Figure 1: EX9250 switches as aggregation devices In a Junos Fusion Enterprise architecture.

Software Functionality

The EX9251 and the EX9253 switches support an extensive set of L2 and L3 services. EX9250 switches are built on Juniper One custom silicon, which supports a wide range of L2 and L3 Ethernet functionality, including 802.1Q VLAN, link aggregation, Virtual Router Redundancy Protocol (VRRP), L2-to-L3 mapping, and port monitoring. Additionally, the line cards support filtering, sampling, load balancing, rate limiting, class of service (CoS), and other key features needed for the deployment of dependable, high-performance Ethernet infrastructure.

EX9250 Routing Engine

The Routing Engine used by the EX9250 line of switches is based on the same field-proven hardware architecture used by Juniper Networks routers, bringing the same carrier-class performance and reliability to the EX9250 that Juniper routers bring to the world's largest service provider networks. The RE's central CPU performs all system control functions and maintains hardware forwarding table and routing protocol states for the switches.

• The EX9251 supports control and management plane functionality with a single integrated RE that features an 8-core, 1.6 GHz Intel processor with 32 gigabytes of DRAM, and an internal fixed SSD providing 100 GB of storage for Junos OS images and logs. Dedicated hardware on the RE supports chassis management functions such as environmental monitoring.
• The EX9253 supports control and management plane functionality with an integrated RE that features an 8-core, 1.6 GHz Intel processor with 64 gigabytes of DRAM and dual front-pluggable SSDs, each providing 100 GB of storage for Junos OS images and logs. Dedicated hardware on the RE supports chassis management functions such as environmental monitoring. Communication between the RE modules and individual line cards takes place over a dedicated internal GbE out-of-band control interface.

Both the EX9251 and EX9253 feature AUX, console, and Ethernet ports on the front panel to support out-of-band system management and monitoring, while an external USB port accommodates a removable media interface for manually installing Junos OS images.

Power

All EX9250 switches support both AC and DC power supplies; however, AC and DC supplies cannot be mixed in the same chassis.

• The EX9251 supports up to two AC or DC power supplies. The AC supplies accept 100 to 240 V AC input and deliver 650 watts of power to the chassis, while the DC power supplies accept -40 to -72 V DC input and deliver 650 watts of power. The EX9251 can be provisioned with either one or two AC power supplies with high line (200-240 V AC) power inputs; one or two AC power supplies with low line (100-120 V AC) power inputs; or one or two DC power supplies.
• The EX9253 supports up to six AC or DC power supplies. The AC supplies accept 100 to 240 V AC input and deliver 6600 W at 110 V and 9600 W at 220 V, while the DC power supplies accept -40 to -72 V DC input and deliver 6600 W of power to the chassis. The EX9253 can be provisioned with three to six AC power supplies with high line (200-240 V AC) power inputs; three to six AC power supplies with low line (100-120 VAC) power inputs; or three to six DC power supplies.

Table 2. EX9253 Power Consumption

Table 3. EX9250 Maximum Power Consumption

Features & Benefits:

Simplified Network Architectures

The EX9250 line of switches is ideal for simplifying campus, data center, and combined campus and data center network
environments by collapsing network layers.

When deployed in a multichassis link aggregation (MC-LAG) configuration in the campus, the EX9250 switches-working in conjunction with Juniper access layer switches like the EX4300, EX3400, and EX2300-eliminate the need for Spanning Tree Protocol (STP) and collapse the core and aggregation layers, dramatically simplifying the network architecture and network operations.

Similarly, in the data center, the EX9250 switches can be used to collapse core and aggregation layers. When used with Juniper access switches in an MC-LAG configuration, the EX9251 and EX9253 reduce the number of managed devices by more than 50% and eliminate the need for STP.

In combined campus and data center environments, the EX9250 line consolidates network layers to simplify the network architecture and operations. In all scenarios, the EX9250 line of switches delivers a simple, secure, virtualized network environment that increases enterprise business agility.

High Availability

When serving as core switches, the EX9250 line delivers a number of high availability features that ensure uninterrupted, carrier-class performance in addition to redundant, hotswappable power supplies and field-replaceable fans. Each EX9253 chassis includes an extra slot to accommodate a redundant RE to serve as a backup in hot-standby mode, ready to take over in the event of a master RE failure. If the master fails, the integrated L2 and L3 GRES feature of Junos OS, working in conjunction with the NSR and NSB features, ensures a seamless transfer of control to the backup, maintaining uninterrupted access to applications, services, and IP communications.

Carrier-Class Operating System

The EX9250 line of switches runs the same Junos OS used by all other Juniper Networks EX Series Ethernet Switches, as well as the Juniper Networks routers that power the world's largest and most complex networks.

By using a common operating system, Juniper delivers a consistent implementation and operation of control plane features across all products. To maintain that consistency, Junos OS adheres to a highly disciplined development process that uses a single source code, follows a single release train, and employs a highly available modular architecture that prevents isolated failures from bringing down an entire system.

Figure 2: EX9250 collapses layers in campus, data center, and combined campus and data center environments.

These attributes are fundamental to the core value of the software, enabling all Junos OS-powered products to be updated simultaneously with the same software release. All features are fully regression tested, making each new release a true superset of the previous version; customers can deploy the software with complete confidence that all existing capabilities will be maintained and operate in the same way.

Simplified Management and Operations

A range of system management options are available for the EX9250 line.

The standard Junos OS CLI provides the same granular management capabilities and scripting parameters found in all Junos OS-powered devices. In addition, integrated Junos XML management protocol tools provide early detection and automatic resolution of potential problems related to the operating system.

Juniper Networks Junos Space software provides system-level management across all EX Series switches, as well as other Juniper products deployed throughout the network-all from a single console.

Juniper Sky Enterprise simplifies the deployment process by building in a "phone home" capability for branch secure router and switches to eliminate pre-staging and allow all management from a central IT operations center. The simple yet flexible solution uses standard SRX Series firewalls and EX Series switches, allowing customization at the operations center where required.

MACsec

The EX9253-12C8Q-M line card supports IEEE 802.1ae MACsec with AES-256 bit encryption, ensuring link-layer data confidentiality, data integrity, and data origin authentication. A single EX9253-SFL license is required for the EX9253 chassis to enable MACsec in software.

Defined by IEEE 802.1ae, MACsec provides secure, encrypted communication at the link layer that is capable of identifying and preventing threats from DoS and other intrusion attacks, as well as man-in-the-middle, masquerading, passive wiretapping, and playback attacks launched from behind the firewall. When deployed on switch ports, MACsec encrypts all traffic on the wire but not inside the switch itself. This allows the switch to apply policies such as QoS, deep packet inspection, and sFlow to each packet without compromising the security of packets on the wire.

Hop-by-hop encryption enables MACsec to secure communications while maintaining network intelligence. In addition, Ethernet-based WAN networks can use MACsec to secure links over long-haul connections. MACsec is transparent to L3 and higher layer protocols and is not limited to IP traffic; it works with any type of wired or wireless traffic traversing Ethernet links.

Scale Licenses

EX9251-ML and EX9253-ML Mega Scale license SKUs enable an EX9250 line chassis to support 512,000 FIB and ARP entries. Only one ML license is required per chassis.

Table 1. EX9250 Features at a Glance

Specifications:

Table 4. EX9250 System Capacity

Table 5. Chassis Specifications

Table 6. EX9253 Line Card Capacities

Documentation:

Download the Juniper Networks EX9250 Ethernet Switch Datasheet(PDF).