Network Function Virtualization (NFV) seeks to replace traditional fixed-function network devices with virtualized network functions (VNFs) that run on shared infrastructure across distributed points-of-presence (PoPs), enabling greater flexibility and scalability. NFV allows for dynamic capacity sharing, automatic scaling, and the ability to repurpose resources in response to varying demands, such as during peak traffic periods. Additionally, it promotes interoperability through standardized interfaces, reducing vendor lock-in and facilitating the development of self-service portals for operators.

1. WHAT IS NETWORK FUNCTION
VIRTUALISATION (NFV)?

2. Network Function Virtualisation (NFV)

3. Virtualised Network Function (VNF)

4. Traditional Model
router
router
router
router
firewall
firewall
firewall
server
server
server
server
server
server
access
gateway
router router
router
router router
firewall firewall
DHCP
DNS

5. Centralised Services
router
router
router
router
firewall
firewall
firewall
server
server
server
server
server
server
access
gateway
router router
router
router router
firewall firewall
DHCP
DNS

6. Geographically distributed Point-of-Presences
(PoPs)
router
router
router
router
firewall
firewall
firewall
server
server
server
server
server
server
access
gateway
router router
router
router router
firewall firewall
DHCP
DNS

7. Geographically distributed dedicated hardware
devices
router
router
router
router
firewall
firewall
firewall
server
server
server
server
server
server
access
gateway
router router
router
router router
firewall firewall
DHCP
DNS

8. Static model
router
router
router
router
firewall
firewall
firewall
server
server
server
server
server
server
access
gateway
router router
router
router router
firewall firewall
DHCP
DNS
● Each device and server has its own fixed function
and capacity.
● Adding more functions or capacity requires more
devices, which is very slow.

9. If something
breaks or
overloads...
router
router
router
router
firewall
firewall
firewall
server
server
server
server
server
server
access
gateway
router router
router
router router
firewall firewall
DHCP
DNS
● Adding replacements or capacity is hard and slow.
● Devices and servers can only fill their fixed function
or role.
● Changes can only be reactive and done manually.

10. Traditional ways to cope with problems
●
●
●
●
●

11. The brave new world of
Network Function Virtualisation
NFV

12. Instead of this …
router
router
router
router
firewall
firewall
firewall
server
server
server
server
server
server
access
gateway
router router
router
router router
firewall firewall
DHCP
DNS

13. NFV offers something like this…

14. Virtualised Network
Functions / devices
● Virtualised network functions run on virtual
hosts on top of the virtualisation
infrastructure in data centers or PoPs
● Virtual infrastructure can extend across PoPs

15. Functions/services/capacity
shared across regions or customer groups

16. Extra capacity
available freely
●
●
●

17. Capacity is general-
purpose capacity
●
●
●
Broadband Customer and Mobile Network PoPs prepare for
prime time in streaming by repurposing capacity to streaming
caches and regional routing and access capacity.
Enterprise customer
fights DDoS with
additional firewall
capacity
Operator prepares for peak
in SMS/MMS messages
Content Service
Provider adds
more capacity
and caching for
prime time
Prime time traffic
requires more firewall
capacity

18. But wait, there’s even more…

19. This is called Network Function Virtualisation
Infrastructure (NFVI)…

20. Each of the small boxes can be
a Virtualised Network Function (VNF) …

21. Each of the VNFs can consist of multiple
components (VNFC) …
Load
balancer
Load
balancer
Packet
Filter
Packet
Filter
Packet
Filter
Packet
Filter
Stateful
Firewall
Stateful
Firewall
Stateful
Firewall
Stateful
Firewall
Policy
and Rule
Database
Policy
and Rule
Database
VNFC VNFC
VNFCVNFC
● Each Virtualised Network
Function Component (VNFC)
may consist of several virtual
hosts, which automatically
scale up and down when
needed.
● VNFs and VNFCs can both
provide e.g. REST or netconf
interfaces for management,
monitoring and integration
purposes.

22. Idea is that VNFCs and VNFs can be re-used…
● … as building blocks of
new VNFs and services.
● They are supposed to
have web services like
REST APIs => web
developers are supposed
to be able to build
operator customer
self-service portals
● Standardised interfaces
should mean better
vendor interoperability
=> avoiding vendor
lock-ins

23. ETSI NFV Architecture and
Interfaces

24. Os-Ma
Ve-Vnfm
Nf-Vi
Or-Vnfm
Vi-Vnfm
Or-Vi
According to ETSI GS NFV-SWA 001 V1.1.1 (2014-12):
Network Functions Virtualisation (NFV); Virtual Network Functions Architecture

25. Os-Ma
Ve-Vnfm
Nf-Vi
Or-Vnfm
Vi-Vnfm
Or-Vi

26. Os-Ma
Ve-Vnfm
Nf-Vi
Or-Vnfm
Vi-Vnfm
Or-Vi

27. Os-Ma
Ve-Vnfm
Nf-Vi
Or-Vnfm
Vi-Vnfm
Or-Vi

28. Os-Ma
Ve-Vnfm
Nf-Vi
Or-Vnfm
Vi-Vnfm
Or-Vi

29. Os-Ma
Ve-Vnfm
Nf-Vi
Or-Vnfm
Vi-Vnfm
Or-Vi

30. VNF architecture
Vn-Nf
SWA-5
Vn-Nf
SWA-5
SWA-4
SWA-3
Ve-Vnfm-vnf
SWA-1
SWA-2
According to ETSI GS NFV-SWA 001 V1.1.1 (2014-12):
Network Functions Virtualisation (NFV); Virtual Network
Functions Architecture

31. VNF definition by ETSI
ETSI GS NFV-SWA 001 V1.1.1 (2014-12):
Network Functions Virtualisation (NFV); Virtual Network
Functions Architecture

32. Summary
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33. For more information about Radiator VNF and
Radiator Software