NSSI
Network Slice Subnet Instance: a component of an NSI representing a specific network domain (RAN, transport, core), which can be shared across multiple network slice instances.
An NSSI is a per-domain piece of a slice. Where an NSI is the whole end-to-end slice instance, an NSSI is the chunk of it living in a single domain — a RAN slice subnet, a transport slice subnet, a core slice subnet — each managed by the management function responsible for that domain.
What makes the concept useful is sharing. An NSSI can be dedicated to one slice or shared across several, so a single core slice subnet might serve multiple NSIs that each have their own distinct RAN subnet. That decomposition is also how slice management is divided up: a domain manager handles its own NSSIs and exposes them upward, and the cross-domain orchestrator stitches NSSIs together into complete NSIs. So the layering goes slice template → NSI (end-to-end) → NSSIs (per-domain components), and most of the reuse and isolation decisions in a slicing deployment happen at the NSSI level.
Related terms
Want to truly understand NSSI? Learn it in context.
NSSI is taught inside our Network Slicing course with diagrams and worked examples. The first module is free with an account; labs, TelcoMentor and the rest of the curriculum are on Pro.
- Free to join
- First module of every course
- No card needed
- TELCOMA since 2009
Get one 5G/LTE engineering deep-dive a fortnight
One thing explained properly every other Tuesday — a real failure, and the lab or trace where you work it yourself. No spam, no marketing, just engineering. Unsubscribe in one click.