Authored by Dayle Wilson, Principal Technical Consultant
Networking is a rapidly changing area of IT. Much of the progress in network infrastructure has gone from ethernet, cable, and fibre optic networks to virtualisation. Network virtualisation is the idea of shifting customer segregation from a VLAN and hardware network devices into software. This is why the term software defined networking is often used to describe network virtualisation.
One of the benefits of virtualisation is the ability to easily move servers elsewhere in the case of incidents such as underlying hardware failure. Because everything is stored in a database, functionality has shifted from a hard-coded configuration on a switch to a piece of software connected to a server. This speeds up the failover process from an administrative perspective, while also driving the trend of single tenancy.
Over the last 15 years, hardware has gone from single tenant devices to multi-tenant devices. Multiple customers had secure access to the same device with separate routing tables. Now, the trend has moved back to single tenant devices located in a virtual appliance. Due to the complexity in managing multi-tenant devices, the shift to a virtualised single tenant design has led to streamlining and simplification.
Of course, virtual networks still live on underlying physical hardware. Therefore, the decision to implement a virtual network will depend on scale and the desired amount of throughput. The underlying hardware will ultimately limit how many virtual customers can live on that piece of software. This limit is generally either 1 gigabit or 10 gigabits, and once that limit is reached it may be necessary to purchase physical equipment and use dedicated cabling for each customer. Throughput of this magnitude still does not work well with network virtualisation.
While virtual networks are very similar to physical networks, there are some clear advantages inherent with virtualisation. Resources can be over-contended, for example—if a customer says they require 1 gigabits/second when they only need 2-300 megabits/second, a physical network would require the purchase of more equipment, translating to a higher cost. In a virtual network, three customers that required 300 megabits/second could all reside on the same underlying 1 gigabit hardware. This would end up resulting in a significant cost reduction.
As the industry switches to a software-defined networking stack, the potential for software bugs is introduced. It usually takes two or three revisions before software becomes mature. Before then, increasing bandwidth demands will eventually hit an unknown threshold. Once the threshold is reached, software bugs will suddenly become apparent. Just as cloud providers and virtualised server resources have gained maturity over the years, the same will eventually happen with networking.
AAA Protocol (Access, Authorisation, and Authentication Protocol) affect networking practices based on who can access network devices and what they are able to accomplish. By controlling access, authorisation, and authentication methods to networking technology, security will become more robust.
If you want to find out more about the latest network trends, contact Macquarie Telecom on +61 2 8221 7777 (or freecall 1800 004 943) or by submitting an online enquiry.