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Leased line failover
A leased line is the envy of all business broadband connections, boasting 99.99% uptime.
However, even this super reliable line can face disruptions. Fibre cables may be accidentally severed during roadworks, or a serious cyberattack could impact your broadband provider’s network.
For businesses that can’t afford downtime, there’s an extra layer of protection: a backup connection to step in if your primary leased line fails.
This guide explores failover connections for leased line broadband, explaining how they work, the different types, and how they can be implemented as part of your business network management strategy.
Contents
- What is failover for leased lines?
- Types of leased line broadband failover
- Why is having a failover important?
- How does a leased line failover work?
- Failover connections for active network management
- Leased line failover implementation
What is failover for leased lines?
A failover is an auxiliary business broadband connection that runs parallel to a principal leased line broadband connection. It serves a backup function if the primary connection fails, ensuring businesses remain online even during network failures.
Failover connections are preferably established on a different route (i.e. through a different exchange) and broadband provider than the principal connection to increase the chances that failure in one doesn’t affect the other.
These auxiliary connections usually have inferior performance (and therefore price) to the primary connection, except in companies critically dependent on very high business broadband speeds.
For example, the multi-connection failover setup below uses a 10Gbps leased line as the primary connection, a 500 Mbps full fibre, and a 100 Mbps 4G mobile broadband as a failover in the unlikely case the leased line goes down.
Types of leased line broadband failover
Four distinct options are suitable as failover connections for leased line broadband, each offering a different level of performance and cost.
| Failover solution | What it is and how it works |
|---|---|
| Leased line failover | Includes setups like RAO2 (resilient access over two circuits) and carrier resiliency with separate infrastructure like Openreach and CityFibre. Ideal for businesses with critical operations where downtime is unacceptable. |
| Tethered broadband failover | Uses a standard broadband connection like SoGEA, cable or full fibre business broadband as a backup. Performance is lower than leased lines but sufficient for maintaining basic operations during outages. |
| Wireless broadband failover | Employs 4G, 5G (business mobile broadband), or satellite business broadband as a backup. Offers faster deployment and (sometimes) better speeds than tethered broadband, particularly with 5G. Satellite broadband ensures coverage in remote areas but may have higher latency. |
| Multi-connection failover | Combines multiple failover solutions for layered redundancy, offering broadband scalability and flexibility. |
Why is having a failover important?
Failover connections are critical for businesses that rely heavily on uninterrupted internet connectivity. Some businesses want to reduce the risk of going offline to the bare minimum, to prevent operational, financial or reputational issues.
Leased line broadband is already the most reliable connection type available to UK businesses and includes the most robust Service Level Agreements (SLAs) that guarantee 99.99% uptime without failover.
Despite this, here are some examples of SMEs that get a failover connection anyway to reduce the risk of connection interruption even further:
| Business type | Why they need failover |
|---|---|
| Independent retailers | Need uninterrupted access to cloud-based POS systems like Square to process in-store and online sales. Without failover, they risk losing sales during peak hours and frustrating customers with long delays. |
| Boutique hotels | Depend on platforms like Cloudbeds for room management and online booking systems to maintain smooth guest experiences. Without failover, guests could face booking errors or overbooked rooms, leading to poor reviews. |
| Private clinics | Rely on cloud systrems for appointment scheduling and access to electronic medical records critical for patient care. A lack of failover could disrupt appointments and delay essential treatments, risking patient dissatisfaction. |
| Fitness studios | Use platforms like Mindbody for scheduling classes and managing memberships, which failover ensures are always accessible. Downtime could lead to missed class bookings and unhappy members unable to access services. |
| IT consultancies | Depend on tools like AWS for cloud hosting and remote management, ensuring seamless client support during outages. Without failover, businesses risk failing to address urgent client issues, potentially losing contracts. |
How does a leased line failover work?
A leased line failover involves a coordinated effort from multiple network components. Here’s an overview of what happens when a leased line connection with a failover fails:
1. Monitoring of the primary connection
Failover systems continuously monitor the status of the primary leased line using automated network monitoring tools like Nagios or SolarWinds. These tools keep track of metrics such as packet loss, latency, and uptime to detect performance issues.
2. Failure detection
The failover mechanism is triggered when the monitoring system identifies a failure or performance drop below a certain threshold. Detection occurs within seconds using protocols like BGP (Border Gateway Protocol) or VRRP (Virtual Router Redundancy Protocol) to ensure minimal disruption time.
3. Switching to the backup connection
The failover system reroutes traffic from the primary leased line to the backup connection. This switch is handled automatically by network management tools, which intelligently determine the best alternative failover connection. The transition is seamless for users and usually takes seconds to activate in the background.
4. Maintaining connectivity
During the failover period, the backup connection takes over fully, keeping all operations online. If the failover connection is not a leased line of the same calibre, there may be slight differences in performance. An SD-WAN can optimise traffic routing over multiple failover connections to maintain application efficiency during this period.
5. Reverting to the primary connection
The failover system automatically switches back once the primary leased line is restored and stable. This reversion occurs automatically without user intervention.
Failover connections as part of active network management
In many real-world scenarios, failover connections are not just kept as idle backups. For instance, SD-WAN allows businesses to actively utilise failover connections for non-critical activities, such as system updates or cloud backups, while reserving the primary leased line for high-priority tasks like VoIP phone systems or real-time transactions.
Alternatively, SD-WAN can distribute all network traffic across all available connections. This network load balancing approach optimises the use of bandwidth to improve overall performance at the expense of leaving less bandwidth to deal with a potential failover.
Leased line failover implementation
Setting up leased line failover is straightforward, especially with the support of a reliable business broadband provider or a managed leased line service. Here’s how to approach it effectively:
- Assess your needs: Identify your critical applications and broadband redundancy requirements. For example, call centres need failover for their VoIP phone systems or UCaaS.
- Choose the right solution: Based on your business’s needs and availability, select the most suitable failover setup. For example, you could use another leased line to make an “RAO2 failover” or an FTTP/SoGEA hybrid failover.
- Install redundant hardware: Deploy the necessary Multi-WAN router(s), network switches, and firewalls to support the failover functionality.
- Configure automatic failover: Use protocols like VRRP or BGP routing to ensure a seamless transition during outages. Larger or multi-site businesses may opt for SD-WAN for routing and SASE to protect against cybersecurity threats.
- Test and maintain regularly: Perform routine failover tests and maintenance to guarantee the system operates reliably when needed.
Key considerations
In addition to this simple approach, consider the following when choosing your preferred failover solution and implementation:
- Costs: A failover connection has a one-time installation fee and a recurring monthly fee. Match the solution to your budget. For more details, see our detailed article on leased line broadband prices.
- Broadband scalability: Make sure you also consider your future broadband requirements. Getting a standard full fibre failover may be cheaper than a secondary leased line in the short term, but only if you don’t need to acquire an extra line moments later.
- Support and maintenance: Always opt for managed leased line services if you lack in-house IT resources. This will boost your business broadband cybersecurity protection.
Leased line failover – FAQs
Our business broadband experts answer frequently asked questions regarding a leased line broadband failover connection.
What is the difference between failover and redundancy?
Failover uses broadband redundancy to function. Failover is switching to a backup system when the primary system fails, ensuring continued operation. Redundancy refers to having duplicate systems or components in place to avoid single points of failure.
Read our full article on business broadband redundancy for more information.
What happens if the principal and failover connections fail?
In this extremely unlikely but possible scenario, your business would be disconnected, and all operations would cease. File transfers and other online processes would just come to a steaming halt.
Having failover connections on top of a leased line (the most reliable connection available) is to reduce the likelihood as much as possible, but the possibility remains present.
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