A serious failure at one of the world's largest Tier 1 IP transit networks (backbone provider), Level 3 Communications, last night (9am ET) triggered huge disruption for global internet services and web servers across the UK, Europe and North America.

Level 3 claims that the "pretty big outage", which downed multiple websites, triggered connectivity problems and caused slower than normal internet performance around the world, was "due to a router manufacturer software issue".

Details remain sketchy, although it's believed that several Juniper Network's EDGE routers crashed and reset their Border Gateway Protocol (BGP) connections. This in turn resulted in a spate of routing problems and connectivity issues for internet providers.

Juniper claims that the issue only affected "a small percentage of customers," which would have been magnified for end-users of the affected ISPs. A software fix was quickly issued for the routers, although by then the damage had been done and it has thus taken awhile for everything to return to normal. Some sites are still recovering.