Enterprise Cloud and Transformation
svenka , Visitor
Enterprise Cloud and Transformation
Welcome QFX5120-48Y!
Jul 3, 2018

I’m excited to introduce our newest addition, the QFX5120-48Y, to Juniper’s QFX5100 Series data center switches. The QFX5100 switches are 10G/40G high density, low latency access/aggregation switches based on Trident chipsets.


qfx 1.png  qfx2 .png


So, what’s new with QFX5120-48Y?

For starters, it is a native 25GbE switch, with 48 25GbE ports and 8 QSFP28 ports for uplinks in a 550ns low latency, 1U form factor. With tri-speed (1/10/25GbE) capabilities on all 48 ports and 40/100GbE on uplinks ports, you have the flexibility of deploying it as a 10/40GbE or 25/100GbE access switch or a combination of 1/10/25GbE for downlink server and storage connectivity with 40GbE or 100GbE uplink to the Spine switches. The 8x100G uplinks provide an oversubscription of 1.5:1 across the 48x25GbE ports connected to the downstream server/storage, which is sufficient for most data center deployments. However, if 1:1 oversubscription is required at the access/leaf layer, it can be achieved by connecting 40x25GbE downlink ports to servers while retaining all the 8x100GbE ports as uplinks. Additionally, the native 25GbE ports are placed together from left to right with the QSFP28 ports grouped to the far right for easier, unambiguous cabling.


QFX5120-48Y highlights include:


  • Advanced Junos OS features such as EVPN, BGP add-path, MPLS, L3 VPN, and IPv6 6PE
  • Feature rich automation capabilities with support for Python and zero touch provisioning (ZTP) 
  • Telemetry streaming tool for performance monitoring, troubleshooting, capacity planning

What are the use cases?

The following table depicts some of the many QFX5120-48Y deployment possibilities.


Port Combinations



48x10GbE + 8x40GbE


10G Access or Leaf

48x25GbE + 8x100GbE


25G Access or Leaf


The QFX5120-48Y is deployed as a leaf either in a distributed gateway architecture where the VXLAN encapsulation and de-capsulation happens at the leaf device or in a centralized gateway architecture where the same is done on the spine device: A flexible placement option!


Here is a depiction of different data center architectures with the QFX5120-48Y switch as a building block. In Figure 1 below, the QFX5120-48Y is deployed as a leaf acting as a distributed gateway. In this topology, the VXLAN tunnel encapsulation and de-capsulation happens on the QFX5120-48Y leaf switches while the spine switch is used as IP transit. Like the QFX5200-32C and QFX5210-64C, QFX5110-32Q switches are also used as a spine for building a 40GbE fabric.




Figure 2 illustrates another use case that the QFX5120-48Y switch addresses - a native 25G leaf device in a centralized gateway architecture with QFX10K switches acting as spine devices. The VXLAN tunnel encapsulation and de-capsulation routing happens on the QFX10K spine switches. Here, the QFX5120, QFX5110, and QFX5200-48Y switches can are configured as leaf nodes in this deployment for a multi-speed scale out leaf/spine fabric.




What about software licenses?

The software features supported on the QFX5120-48Yswitch are categorized into three tiers (Base, Premium, Advanced):

  1. The Base software includes basic Layer 2 switching, basic Layer 3 routing, multicast, automation, programmability, zero touch provisioning (ZTP), and basic monitoring. A Base software features license comes with the purchase of the hardware and does not require any explicit license unlocking keys.
  2. The Premium software feature license includes all the Base features along with BGP, IS-IS, and EVPN Virtual Extensible LAN (VXLAN). This tier requires the QFX5K-C1-PFL
  3. The Advanced software features license includes all the features from Premium tier along with MPLS feature set. These features require the QFX5K-C1-AFL


All this sounds good, but when is it available?

The QFX5120-48Y will be available in 3Q 2018. Please reach out to your Juniper sales rep for ordering and availability.


Datasheet: https://www.juniper.net/assets/us/en/local/pdf/datasheets/1000639-en.pdf

Product Page: https://www.juniper.net/us/en/products-services/switching/qfx-series/qfx5100/

Data Center Solutions: https://www.juniper.net/us/en/solutions/data-center/

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