Neutron (OpenStack)

Neutron (OpenStack)
Name	Neutron
Developer	OpenStack Foundation
Released	2012
Programming language	Python
Operating system	Cross-platform
License	Apache License 2.0

Neutron (OpenStack) Neutron provides scalable, API-driven software-defined networking services for cloud platforms and integrates with compute, storage, and orchestration layers. It exposes pluggable backend implementations and supports rich topology, policy, and connectivity constructs used by projects, vendors, and operators across the Linux Foundation, Red Hat, Canonical Ltd., and IBM. Neutron is threaded into OpenStack distributions and distributions from commercial vendors like SUSE and Mirantis.

Overview

Neutron is the network connectivity-as-a-service component within the OpenStack ecosystem and interacts with projects such as Nova (OpenStack Compute), Cinder (OpenStack Block Storage), Glance (OpenStack Image), Keystone (OpenStack Identity), and Horizon (OpenStack Dashboard). It offers APIs to provision virtual network constructs, manage addressing and routing, and orchestrate multi-tenant isolation used by providers including Rackspace, HP, Cisco Systems, and Huawei. Neutron supports multiple backend drivers and integrates with hardware and software from vendors like Juniper Networks, Arista Networks, Brocade, and Intel Corporation.

Architecture and Components

Neutron’s architecture separates control plane and data plane, with a central server, plugin system, agents, and modular drivers. Core components include the Neutron server, plugin interfaces, ML2 mechanism drivers, L3 agents, DHCP agents, and metadata agents that interoperate with RabbitMQ, Apache ZooKeeper, and etcd in high-availability deployments. The ML2 plugin enables multiple mechanism drivers such as Open vSwitch, Linux Bridge, OVN (Open Virtual Network), and vendor SDN integrations like Contrail and NSX-T Data Center. Neutron agents run on compute nodes alongside hypervisors such as KVM, Xen Project, and VMware ESXi to implement forwarding rules and encapsulation protocols like VXLAN, GRE, and VLAN.

Networking Models and Services

Neutron supports flat, VLAN, VXLAN, and GRE overlay models and provides L2 switching, L3 routing, NAT, DHCP, and floating IP services. Advanced services include load balancing (LBaaS), firewall-as-a-service (FWaaS), VPN-as-a-service (VPNaaS), and Quality of Service (QoS) policies used by operators including Telefonica, Verizon Communications, and NTT Communications. Service chaining is enabled via integration with OpenDaylight, ONOS, and other SDN controllers, while policy and intent are often expressed through Heat (OpenStack Orchestration) templates or third-party orchestrators such as Kubernetes for hybrid scenarios.

Deployment and Integration

Deployment models range from single-node proof-of-concept setups to carrier-grade, multi-region clouds using tools like TripleO, Juju (software), Ansible, Terraform, and Kolla. Neutron integrates with hypervisor platforms including Microsoft Hyper-V and storage controllers from NetApp and Dell EMC for consistent tenant networking. Cloud operators implement CI/CD pipelines using Zuul (software) and test suites from the OpenStack Foundation; commercial distributions manage lifecycle through products from Canonical, Red Hat, SUSE, and Mirantis.

Security and Networking Features

Neutron enforces multi-tenant isolation with security groups, ACLs, and RBAC policies tied to Keystone (OpenStack Identity). It works with firewall and intrusion detection platforms from Palo Alto Networks, Fortinet, and Snort to provide perimeter and micro-segmentation controls. Neutron’s integration with OVN (Open Virtual Network) and OpenFlow controllers enables programmable flow rules and security policy enforcement consistent with compliance frameworks used by enterprises such as Bank of America and Goldman Sachs.

Performance and Scalability

Scaling Neutron requires careful tuning of agents, messaging backends like RabbitMQ, database backends such as MySQL and MariaDB, and the use of techniques like distributed virtual routing (DVR) and provider networks. High-performance data planes use DPDK-enabled vSwitches, SR-IOV passthrough with NICs from Broadcom and Mellanox Technologies, and hardware offloads available in platforms from Cisco Systems and Arista Networks. Large clouds adopt techniques proven by operators like AWS-adjacent research and academic deployments at institutions such as MIT and Stanford University for benchmarking.

Development History and Community

Neutron originated as the evolution of earlier OpenStack networking efforts and was formalized in the OpenStack Havana and Icehouse cycles with contributions from Rackspace, Red Hat, Cisco, and HP. The project is governed through the OpenStack Foundation's technical committee and developed collaboratively on platforms including Gerrit and GitHub with CI driven by Jenkins. Contributors include foundations, vendors, and research groups from Carnegie Mellon University, Lawrence Berkeley National Laboratory, and companies like Mirantis and Canonical Ltd.. Major design discussions occur at OpenStack Summit events and in working groups coordinated with Linux Foundation initiatives and standards bodies such as the IETF.

Category:OpenStack