Introduction to Applications and the Junos SDK
The Junos Software Development Kit (SDK) allows partners of the Junos SDK program to build custom applications that run on the Juniper Networks Junos operating system (OS).
Third-party developers, here called providers, can use the Junos SDK to create innovative applications and manipulate existing features of the Junos OS. The term application, as used in this guide, refers to an application built by a provider using the Junos SDK. Documentation about the Junos SDK is aimed at one of two audiences: the providers that build the applications and the network administrators who install and configure the applications on their network devices. This guide is for network administrators.
Applications run on either a Routing Engine or a services module and so can be thought of as being either Routing Engine applications or service applications, respectively.
- Routing Engine applications run on the control plane. Typically, these applications perform network management and protocol signaling. They also initiate servers. Positioned on the control plane, Routing Engine applications can coordinate other subsystems and services. A Routing Engine is always present in any device, so these applications are always deployable without the addition of any extra hardware or software.
- Service applications run on the services plane. The services plane is specialized to enable high-performance, customized, and stateful packet processing on the transit or monitored traffic selected for servicing. Service applications may also perform operations similar to Routing Engine applications, but such activities typically supplement packet processing.
On some of the smaller Juniper Networks devices, physical modules do not necessarily plug in to a chassis. Rather a single box contains the necessary hardware. Nonetheless, applications are still supported in the control and services planes and we continue to use the Routing Engine and services modules terminology.
For more information about the Junos SDK, please contact your account team or visit the Junos SDK website at https://www.juniper.net/us/en/products-services/nos/junos/junos-sdk/.
