Junos OS
| Company type | Software |
|---|---|
| Industry | Computer software, Network operating system |
| Founded | July 7, 1998 |
| Founder | Juniper Networks |
| Products | Network operating system for routing, switching, and security hardware |
| Parent | Juniper Networks |
Junos OS—also referred to as Juniper Junos, Junos, or JUNOS—is a network operating system originally built on FreeBSD and later adapted to Linux, developed by Juniper Networks. It serves as the underlying software for Juniper's range of routing, switching, and security hardware, forming the backbone of their primary product lineup.
Versions
The initial launch of Junos OS occurred on 7 July 1998. By 2008, updates introducing new features were being released on a quarterly basis.
Architecture
Junos OS predominantly runs on FreeBSD installed directly on bare metal hardware, with subsequent editions incorporating a Linux kernel. As a Unix-based system, it grants users access to a Unix shell environment where standard Unix commands can be executed. The operating system is compatible with most Juniper hardware platforms. After Juniper acquired NetScreen, security functionalities from ScreenOS were merged into Junos.
Variations in Junos OS architecture include:
- Junos OS based on FreeBSD 6 running on bare metal.
- Junos OS utilizing FreeBSD 10 or newer on bare metal, beginning with Release 15.1 on specific devices; starting from Release 16.1, it supports operation as a virtual machine guest on a Linux host.
- Junos OS Evolved, which operates natively atop the Linux kernel, providing direct access to Linux tools and achieving reduced boot durations.
Junos SDK
Within the Junos ecosystem exists a Software Development Kit (SDK), accessible through the Juniper Developer Network (JDN). This SDK empowers external developers to build applications compatible with Junos-driven equipment such as routers, switches, and service gateways. It supplies APIs and development tools covering routing functions, firewall filtering, user interfaces, and traffic management services. Additionally, the SDK supports creation of products like OpenFlow for Junos alongside other traffic-related features.
Command-line interface
The Junos OS command-line interface (CLI) is a text-based utility designed for device configuration, diagnostics, and network monitoring on Juniper platforms. It offers two primary command modes:
- Operational Mode – Used for checking hardware conditions and viewing live network traffic data.
- Configuration Mode – Enables modification of device settings by editing the configuration hierarchy for routers, switches, or security appliances.
FIPS 140-2 security compliance
A specialized version of Junos OS known as Junos-FIPS 140-2 Security Compliance allows configuration of Juniper devices within environments adhering to Federal Information Processing Standards (FIPS), thereby strengthening security measures for government agencies and regulated industries.
Juniper Extension Toolkit (JET)
The Juniper Extension Toolkit (JET) is integrated across all Juniper routers, switches, and security devices running Junos OS. JET facilitates automation of operational workflows, configuration changes, and management processes through open APIs compatible with common programming languages. It enables interaction with the programmable database in Junos OS and supports integration with Trio and Express ASICs via third-party controller adapters such as SAI, OpenFlow, and P4.
Junos Fusion
Designed to streamline network complexity and reduce operational expenses, Junos Fusion presents a logical device framework. It provides two distinct architectures tailored respectively for provider edge networks and enterprise settings, simplifying overall network administration.
Node slicing
Node slicing enables dividing a single physical MX Series router into several virtual routers, each possessing its own control, data, and management planes. This capability allows multiple independent services to operate simultaneously on a single hardware unit, maximizing the efficiency of resource utilization.
Routing protocols and applications
Junos OS accommodates a wide range of routing protocols and functionalities, such as class of service (CoS), Ethernet VPN (EVPN), firewall filters, policers, flow monitoring, and Layer 2 capabilities. It incorporates advanced high availability features beyond traditional Unix systems, including Graceful Restart. Starting with version 9.3 on SRX and J-series devices, Junos introduced "flow mode," which supports stateful firewalling, NAT, and IPsec. The operating system adheres to industry standards for routing and MPLS, promoting enhanced network compatibility and security.
Secure boot
Secure boot strengthens system protection by safeguarding the Basic Input/Output System (BIOS) against unauthorized modifications during the startup sequence, following the Unified Extensible Firmware Interface (UEFI) framework. It begins with secure flash technology to block unauthorized firmware alterations. Approved Junos OS versions are digitally signed by Juniper Networks or authorized partners, guaranteeing the firmware’s authenticity and reliability during the boot process.