Telecommunications networks have historically been distributed by nature. In the United States, for instance, there are roughly 20,000 central office buildings, each of them hosting one or more telephone switches. Technologically and from a usage perspective, it made sense for telecommunications equipment to be distributed.
Data centers operate on the opposite principle, however; it makes a lot more sense to centralize computing into a small number of highly concentrated locations, especially with the rise of virtualized computing and the growing issue of energy use and cooling.
As network operators move to a carrier cloud model, there’s the question of whether they should stay distributed or centralize like the data center.
There are many reasons why decentralization still makes sense for carriers. These include network offload, latency and jitter considerations, reliability, availability, and security.
Whereas voice used to be the primary traffic on the network, it now is video and data. So it is important to keep the data being transmitted closer to the recipient, which lends itself to a distributed model. Latency and jitter with streaming video also are reduced if the video being served needs to travel shorter distances.
Reliability and availability are also improved with a distributed environment, making networks more resilient to disruption and less likely to be affected by natural disasters.
By distributing the network, operators also are better able to protect the network against intrusion because a breach at one location does not have to compromise the whole network.
Thankfully, distributed network functions virtualization (NFV) now makes it possible for the data network to be as distributed as telecommunications historically has been.
“Network Functions Virtualization (NFV) has marked the beginning of a new era in telecommunications networking,” noted a recent Alcatel-Lucent (News - Alert) white paper, Why Distribution Matters in NFV. “The virtualization of network functions on top of an industry-standard server infrastructure, typically a private carrier cloud, provides a radically new technology for building networks.”
These virtual network functions are often decomposed into multiple components that run on different virtual machines, each of which can be placed in the same or different locations.
Source (News - Alert): Alcatel-Lucent whitepaper: Why Distribution Matters in NFV
“Virtualization thus brings heretofore unseen placement flexibility as network functions — and even components of network functions — are no longer tied to specific physical locations,” added the Alcatel-Lucent white paper. “This gives us the flexibility to distribute network functions throughout a geographic area, either in regional data centers, metro areas, neighborhoods, or even on customer premises and mobile devices.”
Edited by Peter Bernstein