5 things businesses need to consider before choosing SD-WAN

Lance Spencer, Director Data Networking and Next Generation Services

In my last blog I outlined how the SD-WAN approach using readily available low cost internet based connectivity does sound rather compelling.

This is especially the case when it is being marketed by companies such as Cisco and Juniper (no-one ever gets fired for choosing these suppliers). But there are a few considerations that need to be thought through when considering SD-WAN.

Here are 5 things businesses should consider:

1. The cost of SD-WAN vs MPLS

The first and most obvious is that taking the SD-WAN approach means all the data is going through the public internet, and not inside a Private Network. This is addressed by the SD-WAN CPE encrypting all the data, so this is well covered, and there is absolutely no doubt on the security as long as the same SD-WAN CPE is used in all sites.

This does mean however that all depots, data centres and distributions sites would need to use the same SD-WAN equipment, which may or may not be suitable.

This also has to be coupled with the consideration that the UK is unusual (if not almost unique) in that the cost of a 100Mb connection to support Private Network (MPLS) for many providers is the same as a 100Mb connection for Internet Access.

So whilst in other countries the cost of SD-WAN equipment can be offset against high MPLS costs to create a business case, in the UK this may not be the case because MPLS is so cheap.

2. Quality of Service (QoS) is lacking from SD-WAN

Quality of Service is the management of delay, delay variation (jitter), bandwidth, and packet loss parameters on a network. It’s essential for applications like VoiP telephony calls or video conferencing, and even new services like Virtual Reality (VR) deployments, as without it these capabilities might be such as poor experience as to not be worth running.

There is no concept of true Quality of Service (QoS) within the SD-WAN based service, so the connection to the site can be flooded with downstream traffic, which will compromise any real-time traffic. And of course, if the end user experience is poor, the network isn’t doing its job well.

3. Fault ownership and resolution

There is the issue of demarcation point between the Telco/Service Provider and the SD-WAN CPE can be a grey area.

In a traditional Managed Private Network, the demarcation is the managed router; so LAN side is the customer and WAN side is the managed service provider. In the SD-WAN scenario, the service provider is often Wires Only, which can lead to fault resolution issues for complex faults.

4. DDoS attacks

With SD-WAN, every site is in effect a Firewall, and has a Public IP address. This means that each site and all sites are vulnerable to DDoS attack.

In the Private Network (MPLS) world, only the centralised firewall would be impacting by the DDoS attack leaving all the internal applications protected and operational.

5. Hybrid networks can offer the best of both

Do customers need to choose between MPLS and SD-WAN? A hybrid deployment can give the customer all the benefits of the SD-WAN CPE deployment, but protects the internal organisation traffic using traditional Private Network (MPLS). The hybrid WAN CPE will make intelligent dynamic routing decisions and will usually be set up to send the low latency real-time traffic across the MPLS network and the none real-time traffic over the Internet VPN.

So is there a clear winner?

SD-WAN offers some innovative capabilities, but it isn’t as compelling to businesses in the UK as it is in other markets, due to the low costs and strong capabilities of MPLS.

So in a market where one size doesn’t fit all, and where customers want choice, TalkTalk Business’ will continue to offer customers and Partners both Cloud-ready public (Internet) and Cloud-ready private (MPLS) networks with a range of optional boosts like Business WiFi, Mobile Backup, SIP, Hosted Voice, Enhanced Monitoring etc.

We believe that this provides the best choice from which businesses can create Private, Public, or Hybrid (a combination of Public and Private) networks to their individual requirements. And of course, these networks are SD-WAN ready, so if organisation wants to overlay SD-WAN capabilities over-the-top of the connectivity, then they can.

I hope you found that useful. If you’d like to contact me about anything you’ve read in this blog then please do so at Lance.Spencer@talktalkbusiness.co.uk.