Amazon.com Inc.’s (AMZN) cloud computing business known as Amazon Web Services is poised to triple its size in five years, hitting $60 billion in revenue according to Wall Street firm Jefferies & Co.

As Amazon’s AWS Summit, its regional cloud computing conference was taking place this week, Jefferies analyst Brent Thill said that with 9,000 attendees, the event has become as big as Amazon’s annual cloud computing confab held in Las Vegas, dubbed re:invent. The crowd size, he said, underscores the popularity of its cloud computing services among companies. In a research report covered by Barron’s, Thill said Amazon Web Services has become the “gold standard for millions of customers” and that its reputation should drive further growth. The analyst noted business will be driven by big and small companies that move more of their work off of their own systems and into the cloud. (See more: Amazon at $1,900 Possible This Year: Goldman.)

“The vast majority of companies we talk to are building on AWS in a big way,”  wrote the analyst in the note to clients. He pointed to recent customer wins including Shutterfly, the photo Website which is moving its image library to AWS and Cox Automotive, which will close forty data centers as it transitions to AWS. What’s more, the analyst said that last week, GoDaddy announced it was kicking off a multi-year transition to Amazon Web Services.  

Going forward, Thill said Amazon Web Services would continue to grow by moving further into the application layer of cloud computing. Currently, it is focused on the infrastructure layer of software only, noted the analyst. Thill also said AWS should make more buys in the security space as security is of the highest importance to its customers as well as the company. Thill, who has a buy rating on the e-commerce giant, said Amazon Web Services also needs to build out a cloud computing hybrid model. “Amazon's partnership with VMware has helped provide a bridge, but we think AWS needs broader access and a more complete hybrid solution, which could fill one of the only notable gaps in the AWS portfolio,” wrote the analyst.

While Amazon’s cloud business only makes up 10% of the Seattle, Washington-based company’s overall revenue, it is a fast-growing segment. In 2017 sales jumped 43% to $17.5 billion. It is now the fifth largest software provider in the world. It faces stiff competition from the likes of Microsoft (MSFT) and Alphabet’s Google (GOOG) which have been steadily chipping away at its dominance. (See more: Microsoft to $1 Trillion in 12 Months: Morgan Stanley.) Still, not every Wall Street watcher is worried about the competition. Goldman Sachs analyst Heath Terry is one of them, saying in a research report last month that it's hard to see how AWS’ leadership position could be taken away by the likes of Microsoft and Google.