Comparing Dual-WAN and Link Aggregation: Tips for Practical Use

In this analysis, we delve into the nuanced distinctions between Dual-WAN and Link Aggregation, as well as their respective setup procedures. As highlighted in our previous discussion on 10Gbps Internet, understanding these configurations is crucial for those seeking optimal network performance.

While Dual-WAN and Link Aggregation may seem like attractive features, they are not universally applicable. For many households, these functionalities may be considered luxuries rather than necessities, thus not justifying the additional expenditure. Consequently, not all Wi-Fi routers come equipped with these capabilities; some may offer either, both, or neither.

It’s important to temper expectations when considering these features on consumer-grade routers. The Dual-WAN and Link Aggregation functionalities in home routers are generally less robust compared to their enterprise counterparts. Given their complexity, these features may pose challenges to the average user.

Multi-Gig technology is increasingly gaining traction, offering superior data transmission speeds and enhanced reliability compared to traditional networks. This emerging technology is especially beneficial for users requiring robust connections capable of handling large files and multiple users simultaneously. Additionally, Multi-Gig networks offer heightened security measures, making them a viable choice for businesses and organisations handling sensitive information.

Individual actions, no matter how minor, can collectively contribute to significant global impact. Conscious decision-making in daily life can lead to positive changes, both for the individual and the planet at large. The cumulative effect of these small steps can be substantial over time.

The digital marketing landscape has undergone significant expansion in recent years. This surge in popularity can be attributed to multiple factors, including the capacity to rapidly reach a broad audience, the availability of analytics for performance measurement, and overall cost-effectiveness. The adoption of digital marketing strategies by an increasing number of companies underscores its growing importance in contemporary business practices.

Dual-WAN and Link Aggregation: Two Distinct Concepts

In the realm of networking, ensuring a stable and fast internet connection is paramount. Whether you’re running a business, managing a smart home, or simply a tech enthusiast, you’ve likely come across terms like Dual-WAN and Link Aggregation. Both technologies offer ways to improve network performance and reliability, but they serve different needs and scenarios. In this guide, we’ll break down the key differences, pros, and cons, to help you decide which solution is best suited for your setup.

Dual-WAN: The Two-Lane Highway

What Is Dual-WAN?Dual-WAN refers to the use of two Wide Area Network (WAN) connections from different ISPs. These dual connections can be configured in two primary ways: Load-balancing and Failover.

Key Features:

  • Load-Balancing: Distributes network traffic across both WAN links, effectively doubling the bandwidth.
  • Failover: Acts as a backup; if one link goes down, the other takes over.


  1. Enhanced Reliability: With two ISPs, you’re less likely to face downtime.
  2. Flexible Configuration: Choose between load-balancing for performance or failover for reliability.
  3. ISP Independence: You’re not tied to the performance or reliability of a single ISP.


  • Cost: Maintaining two separate ISP subscriptions can be expensive.
  • Complexity: Requires a more intricate setup, especially for load-balancing.

Ideal For:Businesses that require high uptime and homes where both performance and reliability are key.

Link Aggregation: The Multi-Channel Approach

What Is Link Aggregation?Also known as port trunking or teaming, Link Aggregation combines multiple network connections in parallel to increase throughput and provide redundancy.

Key Features:

  • Increased Bandwidth: Combines the speed of each link in the aggregation group.
  • Fault Tolerance: If one link fails, traffic is automatically rerouted through the remaining links.


  • Simplified Management: Managed as a single link, making network administration easier.
  • Scalability: Easily add more links to the aggregation group for more bandwidth.
  • Cost-Effective: Often possible to aggregate cheaper links instead of upgrading to a more expensive, higher-speed link.


  • Limited to One ISP: Usually involves multiple links from the same ISP or network switch.
  • Hardware Requirements: Both ends of the aggregated links must support Link Aggregation.

Ideal For:Data centres, large enterprises, or any environment where high data throughput and fault tolerance are crucial.

Contrasting Dual-WAN and Single-WAN Setups

Networks generally employ routers to manage their WAN connection(s) (in the case of Dual-WAN.) This same principle applies to mesh networks as well – satellite units of a Wi-Fi system cannot be used to host an internet connection, regardless if it is the primary or secondary WAN.

At the end of the day, you require a router with Dual-WAN compatibility if you want to make use of this feature.

Two Single-WAN routers cannot provide a Dual-WAN setup. What you will have are two separate networks, and if you connect them together using a Virtual Private Network, only one of the two WAN connections will be used at once.

Having two WAN connections: Is it worth the extra cost for more bandwidth or faster speed?

When talking about an Internet connection, we often use Megabits per second (Mbps) or Gigabits per second (Gbps) to describe the speed of a wide-area network (WAN). To put it simply, the rate at which data is transmitted can be summarized. It’s important to note that every character on a page, including spaces between words, requires one byte of data when reading. When it comes to storage, measurements are usually given in kilobytes (kB), megabytes (MB), or gigabytes (GB). However, for data transmission, the unit of measurement used is bits. A byte is composed of eight bits, and a Megabit (Mb) is equivalent to one million bits.

Nowadays, Megabits per second (Mbps) is the standard for data transmission and is expressed as the amount of megabits manipulated within a single second. In consequence, the following are some of the most commonly used terms:

  • Fast Ethernet: This connection type can provide speeds of up to 100Mbps.
  • Gigabit: Also known as Gigabit Ethernet (GbE), this is the most popular wired connection standard that offers up to 1000Mbps.
  • Gig+: A connection speed that is faster than 1Gbps but not as fast as 2Gbps. Generally applies to Wi-Fi 6/6E or Internet connections.
  • Multi-Gigabit: This is multiple Gigabits, offering speeds of 2Gbps or more.
  • Multi-Gig: This BASE-T standard supports 2.5GbE, 5Gbe, or 10GbE over CAT5e (or higher grade) network cables. It is compatible with Fast Ethernet and Gigabit connections.

It is easy to understand why we all want to check the speed of our internet connection. However, it is important to remember that speed and bandwidth are not necessarily related. Let’s look at a scenario to explain this further:

Let’s say you have a broadband connection with a speed of 500Mbps. If you run a speed test on one device, it would receive 500Mbps. On the other hand, if you run the same test on a different device, you could expect the result to be 0Mbps, or, more likely, 250Mbps, and the first device’s result to be halved.

The total capacity of your Internet link is 500Mb, which is also the highest level of data that it can transmit in any given moment.

In order to acquire two 500Mbps connections at the same time, we’ll need to possess a Gigabit (1000Mbps) link. On the other hand, you can also get two individual 500Mbps lines, which is where Dual-WAN is useful.

Your Internet velocity will not be augmented by Dual-WAN, only the capacity will be increased.

Two 500Mbps broadband plans can provide a benefit as opposed to one 1000Mbps line in that no computer on the network can monopolize the entire bandwidth. With two separate plans, the rate of 1000Mbps can’t be achieved in a single test, however, each device can get the full 500Mbps at the same time.

When it comes to Dual-WAN setups, load balancing is the way to go.

Comparing Dual-WAN: Load-balancing vs Failover

Dual-WAN offers two methods of connectivity – Load-balancing and Failover. Load-balancing allows for the sharing of traffic between two WAN links, while failover provides a backup connection in case one link fails. This article will compare and contrast the two approaches.

Two popular approaches exist when it comes to Dual-WAN setup: load balancing or failover.

Balancing Out the Dual WAN: Boosting Your Bandwidth Capacity

Load-balancing distributes your network traffic across both WAN links. Essentially, it’s like having two motorways instead of one; cars (data packets, in this case) can move along both, reducing congestion.


  1. Increased Bandwidth: You can utilise the combined speed of both ISPs, which is particularly useful for bandwidth-heavy tasks like video streaming or large file transfers.
  2. Optimised Performance: By distributing the load, you can ensure that no single link is overwhelmed, leading to a smoother user experience.
  3. Cost-Effective: If you’re already paying for two ISPs, load-balancing lets you get the most bang for your buck by using both actively.


  1. Complexity: Setting it up can be a bit more complex, requiring a good understanding of networking concepts.
  2. Inconsistent Sessions: Some applications don’t play well with load-balancing and may require a consistent IP address.

Best For:Environments where high bandwidth and optimised performance are critical. Think of a bustling office or a home where multiple people are streaming, gaming, and downloading simultaneously.

Dual-WAN Failover: All about having a reliable system

Failover is like having a spare tyre. If one WAN link goes down, the router automatically switches all traffic to the other, functional link.


  1. Reliability: Provides a backup in case one ISP faces downtime, ensuring uninterrupted service.
  2. Simplicity: Easier to set up compared to load-balancing.
  3. Consistent Sessions: Ideal for applications that require a stable IP address, as all traffic is routed through one ISP at a time.


  1. Underutilisation: One of your ISPs essentially sits idle until the other fails, which might not be cost-effective.
  2. Manual Reversion: Some systems may require manual intervention to switch back to the primary link once it’s up and running again.

Best For:Scenarios where uptime is more critical than bandwidth. This could be a small business that relies heavily on cloud services, or a home where the focus is more on reliability than on multi-tasking.

Setting Up a Dual-WAN Configuration on an Asus Router: Understanding the Basics

Asus Dual Wan

Establishing a Dual-WAN link is not a difficult task. It is the same as configuring a single WAN connection along with an additional one. The following are the primary steps to take with a router that is compatible: setting up a single WAN.

  • Locate the network port for the Primary and Secondary WANs. In this example, the 10Gbps Base-T Multi-Gig port is utilized for the Primary WAN and the router’s default Gigabit WAN port for the Secondary WAN.
  • Connect each WAN port to its individual internet source. For this instance, the 10Gbps Sonic Fiber-optic ONT and the Comcast Cable modem are used.
  • Access the router’s web interface, go to the WAN (Internet) section, and configure the Dual-WAN setting. This example uses both Failover and Load-Balance, one at a time.

We have completed the hardware steps. It was a relatively straightforward process.

For the Dual-WAN settings on a compatible router, such as many Asus routers, one can choose between Failover and Load-Balance (right). The Load-Balance option provides the “Routing rules” feature, which can be used to assign a particular WAN to specific local devices.

  • Primary Setup:
    • Primary WAN: This is the quicker connection to the internet.
    • Secondary WAN: This is the slower connection.
    • Dual-WAN Mode: This must be either Load Balance or Failover. Generally, the former is the default.
  • Auto Network Detection: This configuration will detect when the WAN connection is unavailable and will act accordingly. For a Failover setup, the secondary WAN will be used, and in Load-Balance, the available WAN will have 100% usage. The parameters are as follows:
  • Detect Interval: This is how often the router will check the WAN connection availability. It is best to set this to 30 seconds or higher to avoid the router from overworking. This is the maximum amount of time that the network is without internet when the primary WAN is down, if the Trigger Condition is set to 1.
  • Failover-applicable Settings:
    • Allow Fallback: This allows the router to move back to the primary WAN when it becomes available and the secondary WAN is in use.
    • Failover Trigger Condition: This is the number of times the primary WAN appears to be unavailable before the router switches to the secondary WAN. To know how long the router is disconnected from the internet before it switches, multiply this number by the value of Detect Interval.
    • Fallback Trigger Condition: This is the amount of times the primary WAN is available before the router switches back to it. To know the amount of time the router uses the secondary WAN before going back to the primary WAN, multiply this by the Detect Interval.
  • Network Monitoring: The methods used for the router to find out if a WAN connection is active. The options are:
    • DNS Query: This is fast and safe. However, it is possible that the information is cached, which is not accurate. You should set the Trigger value to higher than 1. You need to use a domain ( Resolve Hostname ) and IP address ( Resolved IP Address ) that have a high uptime. If the domain is down, the router will think the WAN is unavailable. The IP address in the screenshot is for Google’s free DNS service.
    • Ping Target: An IP address or domain that the router can send a Ping command to. This is effective if the domain does not block the ping command. Keep the Trigger value at 1.
  • Load-Balance-applicable Settings:
    • Load-Balance Configuration: This is the bandwidth split between the two WANs. The value can be between 1 and 9, depending on the speed difference between the two.
    • Enable Routing Rules: Rules can be set to make a specific device in the network access a particular public IP address through a specific WAN connection. Generally, about 30 rules can be set, but this is not needed unless there is a special purpose.
Asus Dual Wan 2

In my personal experience, I have found that when you have two asymmetrical WAN connections, the preferred choice is to utilize the Failover setting.

I have found that the process of switching out one of my WAN connections for a test router has been an effective tactic with no problems arising on my home network.

For the majority of households, acquiring Dual-WAN could be too expensive or simply not a possibility. However, in such an instance, two is better than one.

Having said that, let’s proceed to Link Aggregation.

Link Aggregation: Achieving Greater Throughput with Local Connectivity

This technique of connecting multiple physical links together to form a single logical link is known as link aggregation. It is a cost-effective way to increase the bandwidth available to a network by allowing a maximum utilization of the existing local links. Link aggregation also improves the availability of the network, as it provides redundancy in case of failure of any of the links. This results in greater throughput, making it an ideal solution for networks that require high levels of performance.

Combining links, commonly referred to as bonding or Link Aggregation Group (LAG), is a simpler method than using Dual-WAN.

Briefly, it is the process of joining two network connections with the same data rate to form a single link.

For home usage, the most common and usually the only Link Aggregation option is the 802.3ad standard. This protocol is only applicable to Gigabit ports in consumer-grade applications.

Specifically, it is possible to unite two Gigabit ports to create a 2Gbps connection that supplies both Failover capacity and combined bandwidth. Even if one of the two ports fails, there will still be a Gigabit connection from the Link Aggregation Group.

It’s essential to recognize that although a Multi-Gig port can be employed in a link aggregation configuration, it will only operate in Gigabit mode for home uses.

In a situation in which both ends of the link do not possess Multi-Gig ports, it is still possible to realize a 2Gbps connection by combining 10Gbps Multi-Gig port and a Gigabit port.

For both the Wide Area Network (WAN) and the Local Area Network (LAN), Link Aggregation is a possibility. However, it can only be used within the local network and not the service line.

Link Aggregation Groups (LAGs) can be difficult to manage since they necessitate multiple cords. To make the most of it, a router or switch as well as an apparatus that is compatible must be used. To put it another way, the two ends of the joined connection must be compatible.

Link Aggregation on WANs: Not Commonly Encountered

A WAN connection can be increased by Link Aggregation, which involves connecting two network ports on a terminal device, such as a Cable modem, to two ports on a router, thereby creating a 2Gbps connection.

The Motorola MB8600, illustrated by the accompanying photos, has the capability to provide WAN Link Aggregation due to its LAN1 and LAN2 ports.

Utilizing Multi-Gig routers and modems, it is becoming less of a necessity for an Internet service provider to offer 2Gbps broadband to its customers through WAN Link Aggregation. This is viewed as a “shortcut” method.

I have not had experience with WAN Link Aggregation on a personal level.

An extra advantage of LAN Link Aggregation on an Asus router is that it provides an extra bonus.

For a considerable period, I have employed LAN Link Aggregation.

It is true that the majority of Asus routers possess these capabilities. You can join the first and second LAN ports into one 802.3ad LAG, and most Synology NAS servers that have two or more LAN ports are compatible with 802.3ad Link Aggregation (and other LAG types.)

Setting up a network with both an Asus router and a Synology NAS server is straightforward; however, the same process can be applied to any LAG-supported device and switch/router.

  • Utilizing its web interface, construct the Link Aggregation Group (LAG) on the router using LAN1 and LAN2, as seen in the screenshot.
  • Employ two network cables to link the router’s two LAN ports to the server.
  • On the server’s end, in the Network section of the Control Panel, construct a bond making use of the two LAN ports utilizing the Balance-TCP mode, which is synonymous with 802.3ad LAG.

A few years ago, before Multi-Gig was a thing, the only way to get multiple Gigabit connections was through LAG. A server with LAG enabled could then provide full 1-Gig connections to two clients at the same time, helping to increase overall local bandwidth.

In my personal experience, having Link Aggregation is an added advantage.

Comparing Dual-WAN and Link Aggregation: A Recap

Summarizing the two options, Dual-WAN and Link Aggregation, there are a few key differences to keep in mind.

A Dual-WAN setup is one in which a router can handle two different Internet connections, such as Cable and Fiberoptic.

This allows the device to be equipped with two WAN connections, be it through two distinct ports or by reconfiguring one of its LAN ports to serve as the secondary WAN. An alternative is to use the USB port to host a cellular dongle.

By creating a Dual-WAN system, you can increase the likelihood of your network staying online in times of outage (Failover), or you can take advantage of the two Internet connections to obtain greater bandwidth (Load-Balance).

Link Aggregation, also referred to as bonding, is when multiple network ports of a router are connected together to form one connection that has an aggregate bandwidth. In most cases, two Gigabit ports are linked up to offer a 2Gbps link.

Well-known networking providers typically have routers that come equipped with Link Aggregation capability. This feature can be used on either the WAN (Internet) or LAN side.

For the first option, you will need a modem that is compatible with the system. As for the other one, the device plugged into the network should be able to support the protocol. Most Network Attached Storage (NAS) servers can do so.

A Link Aggregation connection not only provides increased bandwidth but also offers the ability to switch over in case of a failure.

Using two distinct broadband connections simultaneously is the concept of Dual-WAN, while Link Aggregation entails combining two identical local connections to form a single faster link. Both of these are techniques to increase bandwidth.

To summarize

For the majority of home networks, neither Dual-WAN nor Link Aggregation is necessary. However, if you are able to employ them, they can be beneficial.

Dual-WAN, although it may involve additional expenses and multiple service lines, is not always practical or even necessary. It is a setup in which a router can handle two different Internet connections, such as Cable and Fiberoptic. This allows the device to have two WAN connections, either through two distinct ports or by reconfiguring one of its LAN ports to serve as the secondary WAN. Another option is to use the USB port to host a cellular dongle. By creating a Dual-WAN system, you can increase the likelihood of your network staying online during times of outage (Failover), or you can take advantage of the two Internet connections to obtain greater bandwidth (Load-Balance).

On the other hand, Link Aggregation, also known as bonding, involves connecting multiple network ports of a router together to form one connection with an aggregate bandwidth. In most cases, two Gigabit ports are linked up to offer a 2Gbps link. Well-known networking providers typically offer routers with Link Aggregation capability, which can be used on either the WAN (Internet) or LAN side. To utilize Link Aggregation, you will need a modem that is compatible with the system, or the device plugged into the network should be able to support the protocol, such as most Network Attached Storage (NAS) servers. A Link Aggregation connection not only provides increased bandwidth but also offers the ability to switch over in case of a failure.

In my personal experience, having Link Aggregation is an added advantage. It not only provides increased bandwidth but also offers a failover mechanism, ensuring a more reliable and uninterrupted network connection.

Comparing Dual-WAN and Link Aggregation, it is important to keep in mind their key differences. Dual-WAN allows the use of two distinct broadband connections simultaneously, while Link Aggregation involves combining two identical local connections to form a single, faster link. Both techniques aim to increase bandwidth.

In conclusion, while Dual-WAN and Link Aggregation may not be necessary for most home networks, they can be beneficial if you have the means to implement them. Dual-WAN allows for increased reliability and greater bandwidth, while Link Aggregation provides increased bandwidth and a failover mechanism. Ultimately, the decision to employ these features depends on your specific network requirements and capabilities.

Paul MacMillan

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