A Guide to Choosing MPLS and Firewall Security Requirements for Business

To choose MPLS and firewall security requirements for your business, start by mapping your sites, applications and traffic, then decide how much guaranteed performance you need between locations (the case for MPLS) and how much inspection and control you need at every internet edge (the job of a firewall). Most multi-site businesses end up with both: a private WAN or SD-WAN for predictable site-to-site traffic, and next-generation firewalls or cloud security for everything that touches the internet. This guide explains each technology, the requirements to define and how to combine them.

What MPLS is and why businesses use it

Multiprotocol Label Switching (MPLS) is a carrier-managed private network technology. Instead of routing each packet by looking up its destination IP address at every hop, the provider’s network attaches a short label and forwards traffic along predetermined paths. For a business, the result is a private WAN that connects branches, offices and data centers across the carrier’s backbone without traversing the public internet.

• Predictable performance: providers typically offer service level agreements for latency, jitter, packet loss and uptime.
• Quality of service (QoS): you can prioritize voice, video and critical applications over bulk traffic.
• Traffic separation: each customer’s traffic is kept logically separate on the carrier’s network.

An important caveat: MPLS isolates traffic, but it does not encrypt it by default. If you move sensitive or regulated data over MPLS, consider adding encryption and treat the WAN as one more network segment to protect, not as a fully trusted zone.

What a firewall does

A firewall enforces rules about which traffic is allowed into, out of and across your network. Traditional firewalls filter by IP address, port and protocol. Next-generation firewalls (NGFWs) go further, with application awareness, intrusion prevention (IPS), URL filtering, malware and sandbox analysis, TLS inspection and user-based policies tied to your directory.

• Threat prevention: blocking known malware, exploits and connections to malicious domains.
• Access control: limiting which users, devices and applications can reach sensitive systems.
• Segmentation: separating guest Wi-Fi, point-of-sale, servers and IoT devices so one compromise does not spread.
• Visibility and logging: recording traffic and events for troubleshooting, audits and incident response.
• Remote access: VPN or zero-trust access for staff working off-site.

Firewalls come as physical appliances, virtual appliances in cloud environments, and firewall-as-a-service delivered from the provider’s cloud. Many carriers bundle managed options; for example, Airtel’s secure internet firewall solutions package connectivity and security for businesses with operations in India, where Airtel is a major provider.

MPLS, dedicated internet and SD-WAN compared

MPLS is no longer the only choice for linking sites. Many businesses combine or replace it with a dedicated internet leased line connection or broadband managed by SD-WAN.

If you are testing whether a link meets its promised latency before or after installation, simple tools help; our guide on how to run a ping test covers the basics.

Defining your MPLS requirements

• Sites and topology: list every location and whether traffic flows hub-and-spoke to a data center or site-to-site (any-to-any).
• Bandwidth per site: measure current peak use and allow headroom for growth over the contract term.
• Application classes: decide which traffic (voice, video, ERP, backups) gets which QoS priority.
• SLA terms: compare uptime targets, latency and jitter commitments, time to repair and the service credits you get if targets are missed.
• Resilience: ask about diverse paths, backup links and last-mile redundancy for critical sites.
• Coverage and lead times: confirm the provider can serve every location, including international sites, and how long installation takes.
• Cloud connectivity: check for direct connections to the cloud platforms you use so cloud traffic does not hairpin through a central site.

Defining your firewall requirements

• Throughput with security features on: vendors often quote raw firewall throughput. Size using threat-prevention or TLS-inspection throughput, which is usually much lower.
• Feature set: IPS, application control, URL filtering, sandboxing, DNS security and identity integration.
• Deployment model: appliances at each site, a central firewall with SD-WAN, or cloud-delivered security for remote users.
• High availability: paired firewalls in failover mode for sites that cannot go offline.
• Management: central policy management, logging retention and integration with your SIEM or monitoring tools.
• Compliance: requirements such as PCI DSS for card payments or HIPAA for health data may dictate segmentation and logging.
• Support and updates: subscription costs for threat intelligence, and who applies patches and firmware updates.

How to integrate MPLS and firewall security

The two technologies work best as one design rather than separate purchases:

• Protect every internet breakout. Whether internet access is centralized at a hub or local at each branch, every exit to the internet needs firewall inspection.
• Do not treat MPLS as fully trusted. Apply firewall rules or segmentation between sites so an infected branch cannot freely reach headquarters servers.
• Align QoS and security policies so inspection does not add unacceptable delay to voice or video.
• Plan for zero trust. Verify users and devices for each application rather than relying on network location, which also covers remote and hybrid staff.
• Centralize monitoring of both network performance and security events so problems are spotted quickly.

Security does not end at the network. Clear data handling rules matter just as much; see our guide to data governance best practices for businesses. For specific use cases like web scraping or privacy testing, some teams also use proxies, covered in boosting online security and efficiency with proxies.

Example: a growing multi-site business

Picture a company with a headquarters, a small data center and a dozen branch offices. Its ERP and phone system run from the data center, while email, file sharing and CRM have moved to cloud services. A sensible design might keep MPLS between the data center and the busiest branches so voice and ERP traffic get guaranteed priority, add a dedicated internet line at headquarters for cloud access, and give each smaller branch broadband with SD-WAN for encrypted connectivity and automatic failover. A pair of next-generation firewalls in high-availability mode protects headquarters, branch SD-WAN devices include built-in firewalling for local internet breakout, and remote staff connect through cloud-delivered zero-trust access. Every component logs to one monitoring platform.

Common mistakes to avoid

• Sizing firewalls on raw throughput, then finding they slow to a crawl once inspection is switched on.
• Backhauling all cloud traffic through headquarters over MPLS, which adds latency and eats expensive bandwidth.
• Leaving default or overly broad “allow any” firewall rules in place after installation.
• Signing long contracts without clear upgrade paths as bandwidth needs grow.
• Skipping regular reviews of firewall rules, logs and patch levels once the network is running smoothly.

Questions to ask providers

• What exactly do your SLAs cover, and how are credits calculated?
• Is the service managed, co-managed or self-managed, and who changes firewall rules?
• How quickly can you add a new site or increase bandwidth?
• What reporting and portal access do we get for performance and security events?
• What are the contract length, renewal terms and early termination costs?

Costs vary widely by region, bandwidth, number of sites and service level, so request itemized quotes covering circuits, hardware, licenses, installation and management fees, and compare total cost over the full contract term.

Frequently asked questions

Is MPLS secure without a firewall?

MPLS keeps your traffic separate from other customers but does not encrypt it or inspect it for threats. You still need firewalls at internet breakouts and ideally segmentation between sites.

Is SD-WAN replacing MPLS?

For many branches, SD-WAN over internet links has replaced MPLS. Others keep MPLS for latency-sensitive traffic and use SD-WAN to add internet links and failover.

What is a next-generation firewall?

A next-generation firewall adds application awareness, intrusion prevention, URL filtering, malware analysis and user-based policies to traditional port and address filtering.

How do I size a business firewall?

Use your peak internet bandwidth plus growth, and compare it with the vendor’s throughput figure for threat prevention or TLS inspection, not the raw firewall number.

What is the difference between MPLS and a leased line?

MPLS is a private WAN linking your sites over a carrier network. A dedicated internet leased line provides uncontended internet access to one site, usually with SLAs.