What is the difference between MPLS & SD-WAN? ...
The key difference between MPLS WAN and SD-WAN is that the latter will typically deliver traffic over the Internet. If your company has a lot of mission critical real time applications (e.g. telephone calls, video conferencing or remote desktop) then this may introduce delays and packet loss, which will cause significant problems with this type of traffic.
SD-WAN
- Uses WAN Virtulisation
- Often uses multiple ISPs and carrier circuits to create a virtual WAN which is then centrally managed by the SD-WAN software application.
- Easy to manage bandwidth allocation for different applications, however as normally traverses the Internet the packet loss will typically be higher than 1%, making it potentially unsuitable for voice or other real time applications where delivered as a standalone SD-WAN and not over the top of e.g. an MPLS network.
- Although QoS control may be offered on the SD-WAN control software, it is impossible to provide this across the underlying network when delivered over the Internet.
- SLAs are often provided but only for the core part of the provider’s network and not the underlying circuits.
MPLS
- Reliable packet delivery i.e. best for real-time applications – closed network therefore doesn’t traverse the Internet and ensures quality. Packet loss is less than 0.01% on the Spitfire core network, with end-to-end SLAs provided when using Spitfire Ethernet circuits.
- Network security through isolation
- Centrally managed site-to-site connectivity
- Quality of Service
MPLS from Spitfire is quick to set up. Once you have a data circuit installed from Spitfire we can then very easily add it in to the MPLS.
What about sites or users that sit outside of the MPLS network? Doesn’t that make MPLS far less flexible than SD-WAN? Not so, we can easily incorporate these sites and users by providing access in to the network using IPSec-VPN tunnels. When creating an SD-WAN, virtual network tunnels are created from sites and users to the central software application in a similar way.
If I go for an MPLS WAN solution, doesn’t that mean that I’m locked in to my ISP? I’ve heard that with SD-WAN I can use any ISP? Whilst it is true that any data circuit can be used with an SD-WAN, many solutions lock you in to an on-site proprietary device, software and control planes. Typically there is an ongoing monthly charging structure to ensure access to controlling software or alternatively large upfront charges for SD-WAN controllers and specialised on-site equipment.
MPLS networks on the other hand are able to use low cost standard routers, with all the configuration taking place on a centralised device. This allows router hardware to be re-used elsewhere if required.
Many current SD-WAN vendors are US based and state boldly that SD-WAN is far cheaper than MPLS WAN. However generally they are referring to US companies that have WANs comprised of MPLS circuits between geographically dispersed states. There are 11 US states that are bigger than the whole of the UK! A circuit from San Francisco to New York is the same distance as a circuit from London to Baghdad!!