What Is BGP and Why Does It Matter for Business Connectivity?
BGP helps networks exchange reachability information across the internet. Learn when it matters to business connectivity and resilience.
The Border Gateway Protocol, or BGP, is the routing protocol networks use to exchange information about which IP address ranges they can reach. Most small businesses never configure it directly, but it underpins the provider paths their services use.
Routes rather than a map of the whole internet
A BGP speaker advertises IP prefixes and selected attributes to neighbouring networks. Each network applies policy to choose and propagate paths. The result is distributed routing: there is no single device calculating every internet journey.
Why businesses may encounter BGP
An organisation may use BGP when it has its own portable address space, an ASN, multiple upstream connections or a hosted platform requiring controlled announcements. It is also central to IP transit services.
Resilience and multihoming
With suitable design, BGP can announce routes through more than one path. If one upstream fails, another may remain. That does not remove shared ducts, power, hardware or configuration risks, and convergence is not the same as uninterrupted application sessions.
Inbound and outbound policy
Networks influence outbound path selection locally and can signal preferences for inbound traffic. Internet routing remains cooperative; a customer cannot dictate every remote network’s decision. Keep policy simple enough to understand during an incident.
Security and route hygiene
Incorrect announcements can misdirect or black-hole traffic. Prefix filters, maximum-prefix limits, controlled change processes and route-origin validation help reduce risk. Administrative access and configuration backups need the same care as other critical infrastructure.
When not to operate it yourself
A single-site business using provider-assigned addresses usually does not need its own BGP session. Managed routing can meet the requirement without transferring operational complexity to an unprepared team.
Learn about I.T Communications’ managed network, where Layer 3 service management is distinct from selected carriers’ Layer 2 access. Speak to our network team about routing and resilience.
A simple multihoming example
A hosted business may announce the same approved prefix through two upstream networks. Normal policy prefers one path, while the second remains available if reachability is withdrawn. The design still needs suitable address ownership, filters, hardware and enough capacity on the surviving route.
Change control is critical because one incorrect route can affect users far beyond the local router. Peer details, prefix lists and rollback commands should be reviewed by another authorised operator before a production change.
