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Campus and Branch

Welcome to the NOW Way to Wi-Fi

Take your networking performance to new heights with a modern, cloud-native, AI-Native architecture. Only Juniper can help you unleash the full potential of Wi-Fi 7 with our AI-Native platform for innovation.
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AI Data Center Networking

Juniper’s AI data center solution is a quick way to deploy high performing AI training and inference networks that are the most flexible to design and easiest to manage with limited IT resources.
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Enterprise AI-Native Networking

Enterprise AI‑Native Routing

Juniper's Ai-Native routing solution delivers robust 400GbE and 800GbE capabilities for unmatched performance, reliability, and sustainability at scale.
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Ops4AI Lab

Visit our lab in Sunnyvale, CA and see our AI data center solution for yourself. You can try out your own model’s functionality and performance, too.
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Enterprise AI-Native Networking

Enterprise AI‑Native Routing

Juniper's Ai-Native routing solution delivers robust 400GbE and 800GbE capabilities for unmatched performance, reliability, and sustainability at scale.
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Higher Education

Shaping Student Experiences: The NOW Way to Build Higher Education Networks

Juniper Networks CIO Sharon Mandell and a virtual summit of C-level IT leaders from prestigious institutions discuss ongoing efforts to support digital transformation on campus.
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Security in healthcare

In this IDC Spotlight report, discover how AI networking can automate and strengthen a healthcare ecosystem to defeat criminals and prevent loss. 
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Retail

The Future of In-Store Technologies

Retail experts Kevin McCartan, Senior IT Service Delivery Engineer at Musgrave; Jack Stratten of Insider Trends; and Christian Gilby, Senior Director of Product Marketing at Juniper Networks, discuss customer experiences.
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ACX7020 router

Juniper ACX7020 Cloud Metro Access Router

Legacy networks simply cannot meet the demands of today’s rapidly evolving metro landscape. Unlock a new generation of highly scalable architectures and automated operations with the Juniper ACX7020. 
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EX4000 Ethernet Switch

Next-gen AI-Native EX4000 line of switches

Lack of AI innovation from your current networking vendor slowing you down? Embrace Juniper’s cloud-native, AI-Native access switches that support every level and layer, across nearly every deployment.
Discover how
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The Q&AI Podcast

Delivering practical solutions and enriching discussions, this podcast series is a vital resource for those seeking an in-depth exploration of AI's transformative potential.
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Juniper AI Care Services Revolutionize Your Service Experience

Our industry-first AI-Native services couple AIOps with our deep expertise across the full network life cycle. You can move from reactive response to proactive insight and action.
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Juniper AI Data Center Deployment Services Optimize Your AI Model Runs

We use our expertise and validated designs to help design, deploy, validate and tune networks, including GPUs and storage, to get the most from your AI infrastructure operation.
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Home Documentation Junos OS Release Notes: Junos OS Release 21.2R2 for the ACX Series, cSRX, EX Series, JRR Series, Juniper Secure Connect, Junos Fusion, MX Series, NFX Series, PTX Series, QFX Series, SRX Series, vMX, vRR, and vSRX Junos OS Release Notes for ACX Series What's New What's New in 21.2R1

Release Notes: Junos OS Release 21.2R2 for the ACX Series, cSRX, EX Series, JRR Series, Juniper Secure Connect, Junos Fusion, MX Series, NFX Series, PTX Series, QFX Series, SRX Series, vMX, vRR, and vSRX

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Release Notes: Junos OS Release 21.2R2 for the ACX Series, cSRX, EX Series, JRR Series, Juniper Secure Connect, Junos Fusion, MX Series, NFX Series, PTX Series, QFX Series, SRX Series, vMX, vRR, and vSRX
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{ "lLangCode": "en", "lName": "English", "lCountryCode": "us", "transcode": "en_US" }
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Dynamic Host Configuration Protocol

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  • Support for persistent storage of DHCPv4 and DHCPv6 bindings over EVPN IRB (ACX5448, ACX5448-D, and ACX5448-M)—Starting in Junos OS Release 21.2R1, ACX5448, ACX5448-D, and ACX5448-M routers that are configured to function as a DHCP relay agent can also be configured to preserve the DHCPv4 and DHCPv6 subscriber bindings across reboots. Existing bindings are written to a local file in /var/preserve. After reboot, the binding table is populated with the contents of the file, and the router identifies each subscriber that was on the deleted interface, and resumes normal packet processing for subscribers when the interface is restored. To preserve the subscriber binding information, enable the perisistent-storage statement at the [edit system services dhcp-local-server] hierarchy level.

    [See Preserving Subscriber Binding Information and DHCPv6 Relay Agent Overview.]

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