When I use curl to test Speech-to-text API of cognitive service, I ran into HTTP 403 and 408 errors.
The tutorial is here: Get started with the Speech REST API in cURL.
When you generate an access token with the first step, you would receive something like:
eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzY29wZSI6Imh0dHBzOi8vc3BlZWNoLnBsYXRmb3JtLmJpbmcuY29tIiwic3Vic2NyaXB0aW9uLWlkIjoiM2ZlNmRlMDY5YTAwNDRjZjgyMzUzYmNhNTY1MDRiZDMiLCJwcm9kdWN0LWlkIjoiQmluZy5TcGVlY2guUHJldmlldyIsImNvZ25pdGl2ZS1zZXJ2aWNlcy1lbmRwb2ludCI6Imh0dHBzOi8vYXBpLmNvZ25pdGl2ZS5taWNyb3NvZnQuY29tL2ludGVybmFsL3YxLjAvIiwiYXp1cmUtcmVzb3VyY2UtaWQiOiIiLCJpc3MiOiJ1cm46bXMuY29nbml0aXZlc2VydmljZXMiLCJhdWQiOiJ1cm46bXMuc3BlZWNoIiwiZXhwIjoxNTAwMDA4MDUyfQ.Q4XLfarJiVXDjIV9Q965QmyQOVcfW5-DV4LSUxxjVcE* Connection #0 to host api.cognitive.microsoft.com left intact
* Connection #0 to host api.cognitive.microsoft.com left intact indicates the end of responses.