What is multihoming?

Multihoming means connecting a network to the internet through at least two independent providers at once, so that the network does not depend on any single link or operator. A multihomed network advertises its prefixes over BGP to all of its upstreams simultaneously and stays reachable even if one provider fails. This is how you build resilience and independence at the edge of the internet. Operators, hosting companies and larger enterprises all use it.

What multihoming requires

True BGP-level multihoming requires several things from a network. First, address space and an ASN that are independent of any single provider, because addresses assigned by one operator are not suitable for advertising through another.

• Your own public ASN, which the network uses to identify itself in BGP to all upstreams.
• Independent address space (PI space or your own RIR allocation), not PA addresses assigned by a single provider.
• A BGP-capable router able to accept routes from providers and advertise your own prefixes.
• At least two links to different, independent providers, ideally over diverse physical paths.

Benefits of multihoming

The most important benefit is redundancy. A single provider's outage does not cut the network off from the internet, because traffic automatically shifts to the remaining links. Multihoming removes dependence on one operator (vendor lock-in) and gives negotiating leverage. It also lets you steer traffic and route different streams through different providers, for example local traffic over cheaper peering and the rest over transit. Availability goes up, and you get better control over connection quality.

Traffic steering and the load-balancing myth

A common misconception is expecting multihoming to spread traffic evenly across all links on its own. BGP picks a single best path for each prefix and does not load-balance per packet, so the traffic distribution has to be shaped with policy. For outbound traffic you use the local-preference attribute to prefer a specific provider. Inbound traffic is harder to steer, most often via AS-path prepending, the MED attribute or selective prefix advertisement. Full, even use of all links requires deliberate design and does not happen on its own.

Multihoming with AS202520 SkyPass

AS202520 SkyPass works well in a multihoming architecture and combines full IP transit with dense peering at Polish internet exchanges. For an operator building redundancy we provide a stable BGP link with low latency to domestic traffic, support in configuring sessions and steering traffic, and remote IXP access where needed. Our upstream can then be both the primary path for local traffic and an independent safety net alongside another provider.