What is the most common remote access protocol?

In the realm of cryptocurrency and finance, remote access protocols play a crucial role in securely connecting users to various financial services and platforms. Could you elaborate on what the most common remote access protocol is? Understanding its prevalence and usage within this domain could help practitioners make informed decisions when selecting the most suitable method for accessing their financial accounts and data. Is it SSH, VPN, RDP, or perhaps another protocol that has gained widespread adoption in the industry?