Many organisations utilize MPLS (Multiprotocol Label Switching) networks to deliver critical business applications to their users and customers. There are relatively high ongoing costs associated with MPLS and so there are opportunities for organisations to realise significant costs savings by migrating to Internet based circuits. However, what are the performance and security consequences of moving from MPLS to Internet?
We've been designing, maintaining and fixing data networks for 20 years so we've seen a lot of networking initiatives that have worked out well and many that have not. In this blog I'd like to share some of our learnings and how one may go about reducing costs associated with MPLS networks. Here are the top six considerations when migrating from MPLS to Internet.
1) Transition Period:
It's best practice to run both MPLS and Internet WAN (Wide Area Network) side by side for as much time as required until you are satisfied with the performance and security of your new network. You can start migrating applications over one by one by putting your applications on different network subnets/VLANs, changing default routes on particular servers or by routing traffic using PBR (policy based routing).
2) Performance Baselining:
Don't rely exclusively on your users to tell you if the new (Internet) network is better/worse than the old (MPLS) network as users can be very subjective. In order to find out if the Internet network is performing as well as the MPLS network you need to baseline the performance of the MPLS network then measure performance of the Internet network using a performance measurement tool. Having a before / after comparison for network quality (delay, jitter, loss, availability) and application utilization (peak usage, applications, websites, users, etc) is the best way to compare the two networks.
3) High performance and high availability Internet:
Did you know that in most cases Internet traffic is sent down the same physical lines as MPLS traffic? Sometimes network operators prioritize certain types of traffic, e.g. MPLS traffic and Premium Internet have priority over standard Internet. When you purchase your Internet circuits ask your network operator about business grade or premium Internet services and also find out about contention ratio's. If possible ask for customer references for services running from the same exchange (ie. in your neighbourhood). Regardless of what your network operator tells you the 'Performance Baselining' step above will ultimately confirm the performance.
Where possible use the same network operator to provide ALL the Primary Internet links, and use a different network operator to provide the Secondary Internet links. If you are running your network globally it may not be possible to have just two suppliers, in this case limit the number of network operator suppliers to the minimum amount. This is important as it reduces the number of interconnects your traffic has to pass through which can cause bottlenecks, latency and additional hops.
For very high availability its a smart idea to run two different internet suppliers in each location and use two different technologies. e.g. Ethernet from one supplier and 4G from the other. Therefore an outage in one technology doesn't bring down the other link.
4) Application visibility and traffic shaping:
When the network manager has powerful application visibility and traffic shaping capabilities on the network they can very quickly see and fix performance issues and ensure critical business applications do not suffer due to congested links. Every single network needs to have application visibility and traffic shaping, especially when considering migration from MPLS to Internet WAN.
A good traffic shaping solution can effectively bring MPLS CoS (Class of Service) back into an Internet WAN, provided you have guaranteed bandwidth / premium internet from your network supplier. This will allow you to reliably run services like telephony (VoIP) over the internet links.
5) Hybrid WAN:
It may be beneficial to keep both networks (MPLS and Internet) in some (or all) of your locations. For example you may find it a viable exercise to keep MPLS running in the data centres and larger locations and run with Internet WAN in smaller locations. Or you may select to keep a smaller (and less expensive) MPLS line in all locations to run quality-sensitive services like VoIP and then use the Internet WAN to run the heavier applications (like backups, email, etc). Most organisations won't need to run a Hybrid WAN but it can be the right setup in certain environments.
I will not get into the details of security in this blog, but will say that you require a gateway (or router) with firewall and data encryption capabilities when migrating to an Internet WAN. With MPLS there is existing but somewhat minimal amount of security to your data offered via the network operator. You can replicate (and surpass) this level of security in your WAN with most reputable firewall / routers available in the market today. One example is Cisco's iWan (Intelligent WAN) technology.
Migrating from MPLS to Internet can save a lot of money and should be considered by organisations when reviewing network design. At Sinefa, we have helped many customers successfully migrate to MPLS and at the same time have increased the performance of the network in the process. Network performance increases because well-managed Internet WANs outperform poorly-managed MPLS networks.