A wave of short internet outages hit on the sites and programs of numerous financial institutions, airlines and other businesses throughout the world Thursday.

The Hong Kong Stock Exchange said in a post on Twitter Thursday day Hong Kong period that its website was confronting technical problems and that it had been exploring. It stated in another article 17 minutes after that its sites return to normal.

Internet tracking sites such as ThousandEyes, Downdetector.com and fing.com demonstrated heaps of disruptions, like to the four biggest U.S. airlines.

A number of the outages were reported by men and women in Australia attempting to perform banking, reserve flights and accessibility postal services.

Australia Post, the nation’s postal service, stated on Twitter an”external outage” had affected a range of its solutions, and that although many services had come back on the internet, they had been continuing to track and explore.

The Reserve Bank cancelled a bond-buying performance as a result of technical issues facing many banks which were to engage.

Services have largely been revived.

Virgin Australia said flights were mostly operating as scheduled following it revived access to its site and guest contact centre.

“Virgin Australia was among several organizations to undergo an outage using the Akamai content delivery program now,” it stated. “We’re working together to make sure that necessary steps are taken to avoid such outages from reoccurring.”

The disruptions occurred late at night at the U.S., when couple of planes were taking away airline agents stated there was little to no impact on flights.

Southwest, which has endured two additional, unrelated tech problems this week, stated its own site along with other web-based tools were temporarily disconnected but flights weren’t affected. United stated there weren’t any lingering problems early Thursday.

Akamai, located in Cambridge, Massachusetts, counts a number of the world’s most important banks and companies as clients.

The disruptions came only days following lots of the world’s top sites went offline temporarily because of a issue with applications at Fastly, yet another significant web services firm. The business blamed the problem using a software bug which was triggered when a client changed a setting.

Brief online service outages aren’t rare and are only infrequently caused by hacking or other mischief. However, the outages have underscored how crucial a few behind-the-scenes businesses have become into conducting the world wide web.