SD-WAN vs MPLS: site networking for business in 2026
Florian Hödl
Network Monitoring and Automation
Summary: MPLS is a private network run by a carrier, with service classes and one SLA for the whole path. SD-WAN is software that steers traffic over whatever lines you have. SD-WAN is not cheaper by definition: the cost moves from the carrier to lines, licences and operation. Most networks end up hybrid. The line underneath SD-WAN decides its quality. Anexum does not sell SD-WAN; it sources and operates the lines beneath it.
If you connect several sites, you are being asked one question above all: SD-WAN or MPLS? Usually it comes from a carrier or a firewall vendor, and usually the answer comes with it. This article compares both factually. Through Managed Connectivity, Anexum supplies and operates lines of the kind that sit under such overlays. Whether an SD-WAN holds up is often decided by the line underneath rather than by the software.
What is MPLS?
MPLS (Multiprotocol Label Switching) is a method by which a carrier forwards packets through its network by labels instead of IP addresses. When businesses say MPLS, they usually mean an MPLS VPN: a private Layer 3 network that the carrier operates and in which all sites can talk to each other directly (any-to-any). Traffic does not cross the public internet. The carrier offers service classes (QoS), so voice can take priority over a file download, and commits to an SLA for the whole path between two sites.
Is MPLS a leased line?
Short answer: No. MPLS is a network service. A leased line is the line that connects a site to a network.
Even with MPLS, every site needs an access line to the nearest point in the carrier's network. That access is often a dedicated line, but the line is not the MPLS. What makes a line dedicated and when business fibre is enough is covered in leased lines for business.
How much does MPLS cost?
Austrian carriers do not publish MPLS prices, so we do not quote any. The cost depends on the same factors as any multi-site network: number of sites, bandwidth per site, service classes booked, SLA tier, contract term and the type of access at each site. A reliable price only comes from a site list.
Where MPLS is still sold
MPLS has not gone away. A1 International Services, the wholesale unit of the A1 Group, describes a global MPLS Layer 3 network with international partners (https://internationalbusiness.a1.group/data/, accessed 29 Sep 2026). Whether and in what form MPLS is sold to businesses in Austria does not follow from that page.
In favour of MPLS: predictable latency and jitter, one accountable carrier, a mature technology. Against it: internet access usually runs through a central breakout, new sites depend on provisioning in the carrier's network, there is usually no direct path to the cloud, and you are tied to one carrier's network and reach.
What is SD-WAN?
SD-WAN (software-defined WAN; a WAN is the network between your sites) is overlay software on edge devices at each site. It continuously measures latency, jitter and packet loss on every available line and steers applications onto the best path according to policy. A central controller distributes those policies. The software does not care which lines sit underneath: dedicated internet access (DIA), business fibre, 5G, or MPLS.
Four building blocks belong to it:
- Edge: the device at the site that measures the lines and distributes traffic.
- Controller (orchestrator): the central point for policy, configuration and overview.
- Overlay: the encrypted tunnels between edges that carry the traffic.
- Underlay: the physical lines underneath, that is, what the carrier delivers.
Typical functions are application-aware routing, QoS, direct internet breakout at the site, zero-touch provisioning of new devices, central policy and optional integrated security.
What carriers in Austria offer
Magenta offers an SD-WAN in Austria built on Versa. According to the vendor, SLAs are selectable, support runs around the clock, new sites should be connected within a few days, the SD-WAN can be combined with existing MPLS lines, and existing main/backup setups can be run active-active. Source: https://www.magenta.at/business/loesungen/standortvernetzung/sd-wan (accessed 29 Sep 2026).
SD-WAN vs MPLS: the direct comparison
The table lists eight criteria. It gives no scores, because which column fits depends on your sites.
| Criterion | MPLS | SD-WAN | |
|---|---|---|---|
| Architecture | Carrier's private network | Overlay of tunnels | |
| Who runs it | One carrier | You, carrier or integrator | |
| Latency and jitter | Service classes, values per SLA | Measured, not guaranteed | |
| SLA | One SLA per path | Per line, plus overlay | |
| Cloud access | Usually central breakout | Direct breakout possible | |
| New sites | Provisioning in carrier network | Edge plus available line | |
| Cost structure | Access, bandwidth, network service | Lines, edges, licences, operation | |
| Security | Private, usually unencrypted | Usually IPsec, edges face internet |
On cost: SD-WAN removes the premium for the MPLS network service, but brings edge hardware, licences, usually two lines per site and operating effort. Whether it is cheaper overall depends on the number of sites, the remaining term of existing MPLS contracts and line prices at each individual site. Savings percentages quoted without a site list and offers are marketing.
Where SD-WAN hits its limits
The limits almost always sit below the software.
The overlay does not fix a bad line. If both lines of a site run in the same duct, one excavator takes out both. If the only line is contended fibre, application steering has nothing to switch to.
Latency-sensitive traffic needs a line with predictable latency. Voice, terminal sessions and industrial protocols react badly to variation. SD-WAN measures that variation and avoids it when a second path is better. It cannot guarantee them.
Typical pitfalls in SD-WAN projects (general practice):
- Two "redundant" lines that run with the same carrier or over the same wholesale access. How Anexum checks independence is in the FAQ on 5G backup and failover.
- 5G backup without a data-volume policy, so the SIM is used up after a day.
- No failback test: the switch to the backup line was never tried, and neither was the way back.
- Business fibre or 5G without a static IP address at the site, so VPN peers no longer match after a switch.
- Security policies left at the vendor's defaults.
- A controller in a single cloud region.
Someone has to monitor the lines. An SD-WAN dashboard shows that a path is bad. It does not open a ticket with the carrier or follow it up. That work stays with the underlay: internet and WAN monitoring per line, carrier escalation, SLA follow-up. How monitoring should be built so that alerts stay useful is described in the network monitoring guide.
Why most networks end up hybrid
Reliable market data is scarce. The TeleGeography WAN Manager Survey (published 25 August 2026) is one of the few. Source: https://resources.telegeography.com/the-rise-of-dia-over-mpls (accessed 29 Sep 2026).
- MPLS averaged 22% of sites in 2025, against 82% in 2018.
- Dedicated internet access rose from 27% to 54% of sites over the same period.
- 74% of respondents still use MPLS at at least one site, and 96% use DIA.
These are global figures. We have no figures for Austria and we do not estimate them.
What follows: MPLS stays at critical sites and where internet quality is poor. DIA becomes the standard line underneath. The migration happens site by site as contracts expire, not in one step. Magenta's product page also describes mixed operation with existing MPLS.
The line underneath: DIA as underlay
There are four options for the underlay at each site:
- Dedicated internet access (DIA): committed bandwidth, symmetric, with an SLA and a defined repair time. The details are in the post on the leased line (DIA).
- Business fibre: fast and affordable, but best effort.
- 5G: mobile, as backup or for temporary sites.
- Existing MPLS: where the contract still runs or latency counts.
A common design, not a standard: sites with servers, voice gateways or many users get DIA plus 5G from a second carrier. Small sites get business fibre plus 5G. Temporary sites such as construction sites get 5G with monitoring. The overlay is chosen after the lines, not before. Which product classes exist in Austria and how to read a service description is covered in the comparison business internet in Austria.
Checklist for an underlay without a weak point:
- Separate carriers for primary and backup line.
- Separate building entries where possible.
- Separate technologies, for example fibre and 5G.
- Static IP address on the primary line.
- A failover that has actually been tested, including the way back.
Worked example, not a promise: two lines at 99% availability each give 99.99% on paper, but only if their outages occur independently. If they share a duct, a carrier or a power supply, it stays at 99%.
What Anexum offers, and what it does not
Anexum does not sell or operate SD-WAN edges or controllers. For SD-WAN projects, Anexum sources and operates the access lines (internet access, business fibre, 5G), provides redundancy per site, and runs provider management and monitoring across all of them. The overlay comes from the SD-WAN vendor or the IT partner. Anexum is not a network operator and is listed with the RTR as a reseller (entry 5265). You sign the contract with Anexum, and Anexum is your point of contact and first-level support. The carrier delivers and operates the line; faults go through Anexum to the carrier.
If your company runs an SD-WAN, whether its own, through a carrier or through an integrator, we take care of the underlay: availability check per address, tender, contract review, installation coordination, monitoring, carrier escalation and SLA follow-up.
Point-to-point Ethernet lines (Layer 2) and MPLS are explained here, but not offered.
More at Managed Connectivity and Managed Business Internet.
Decision guide: five questions before you switch
1. How many sites do you have, and which of them cannot tolerate an hour of downtime? Those sites get two lines from separate carriers, whether you use MPLS or SD-WAN. For the rest, one good line with 5G backup is often enough.
2. Which applications need guaranteed latency? Voice, terminal sessions (RDP) and machine protocols. Measure latency and jitter today, before you decide. If an application only works with predictable latency, its site belongs on DIA or MPLS, not on a best-effort line.
3. When do your existing MPLS contracts expire, site by site? Switching before the term ends usually means paying twice. A list with end date and notice period per site shows the order in which you can migrate. Contracts often renew automatically when the notice period passes.
4. Which lines are actually available at each site? Availability decides more than architecture. Check it per address before you fix the design. A design that works at ten of twelve sites is not a design.
5. Who runs the overlay and the underlay, and who calls the carrier? If they are two different parties, it must be clear who checks first during an incident and who owns the ticket with the carrier.
You have several sites and want to know which lines are possible there? Have sites and lines checked.
Frequently asked questions
What is the difference between SD-WAN and MPLS?
MPLS is a private network run by a carrier, with service classes and one SLA for the whole path. SD-WAN is software that steers traffic over any lines, MPLS included. They are not opposites: an SD-WAN can use MPLS as one of several lines.
Is MPLS a leased line?
No. MPLS is the carrier's network service. The line that connects a site to it is the access, and that can be a dedicated line.
Is SD-WAN cheaper than MPLS?
Not by definition. SD-WAN saves the premium for the MPLS network service, but adds cost for edge devices, licences, usually two lines per site and operation. Whether it is cheaper depends on the number of sites, the remaining terms of the MPLS contracts and line prices on site. Percentages without a site list are marketing.
Can SD-WAN fully replace MPLS?
At many sites, yes. At latency-critical or poorly connected sites, MPLS often stays. According to TeleGeography (global, 2025), MPLS averaged 22% of sites, yet 74% of respondents still used it at at least one site. In practice, hybrid networks result.
Which internet lines does SD-WAN need?
At critical sites a dedicated internet line (DIA), at small sites business fibre plus 5G. The two lines at a site should come from different carriers and, where possible, run on different technologies.
Does Anexum offer SD-WAN?
No. Anexum supplies and operates the lines under an SD-WAN: internet access, redundancy, provider management and monitoring. The overlay comes from the SD-WAN vendor or the IT partner. If you run an SD-WAN, we take care of the underlay. More at Managed Connectivity.
What is a WAN, in simple terms?
A WAN (wide area network) is the network between your sites. A LAN (local area network) is the network inside one site.
Have the underlay checked
If you are planning an SD-WAN or already run one, we are happy to check the lines beneath it: availability per site, carrier diversity, contracts and notice periods. Have sites and lines checked.
If you still run MPLS, the free provider audit shows notice windows and terms per contract.
As of: 30 September 2026.
Sources (all accessed 29 Sep 2026):
- TeleGeography, The rise of DIA over MPLS (WAN Manager Survey, 25 Aug 2026): https://resources.telegeography.com/the-rise-of-dia-over-mpls
- Magenta, SD-WAN: https://www.magenta.at/business/loesungen/standortvernetzung/sd-wan
- A1 International Services, portfolio: https://internationalbusiness.a1.group/data/
- Wikipedia, SD-WAN: https://en.wikipedia.org/wiki/SD-WAN
- Wikipedia, Multiprotocol Label Switching: https://en.wikipedia.org/wiki/Multiprotocol_Label_Switching