Older routers hit capacity limits.
Websites and network providers such as eBay, Comcast and Time-Warner have been hit by outages and connectivity issues due to an overflow of traffic routes between networks, which pushed core routers over their default limits.
According to the North American Network Operators Group (NANOG) and complaints tracker DownDetector, many companies including Verizon, Level 3 and Sprint suffered performance problems on Tuesday.
Networking experts have blamed the Border Gateway Protocol (BGP) Internet routing table – the routing protocol used by ISPs and networks to route data – which has been constantly growing in size as the Internet continues to expand and becomes more complex.
Hosting provider Liquid Web on Tuesday posted on Twitter: "As ISP’s have recovered from #512k active BGP routes being reached, many of our customers affected by these carrier issues have regained the ability to reach their sites.
"We are still currently up, working to get a timeframe when sites can be reached from all locations and from any ISP."
In order to deal with the increase in web traffic, routers, which can only accommodate for 512K routes, need to be updated with more memory and processing power.
Cisco, which warned its customers in May that the rising number of route entries could pose trouble, has published workarounds for this issue on its site.