What is Akamai HTTP Response Code 000 means ?

We know a traditional HTTP Server Response codes like 200, 404 and 500 . But Akamai Content Delivery Network follows slightly additional set of HTTP Status codes like 000 .

Here is the details of Akamai Edge HTTP Response Codes mentioned in Akamai KB Article

OK: content was delivered to the client (200, 206, 408)  

Not-Modified: a positive response to a content freshness request (304) 

Redirect: a redirect response was returned to the client (301, 302)

Not-Found: an unknown object was requested (404)

Permission: a permission denied or HTTP basic auth response (415, 403, 401)

Gateway Error: usually an issue with the origin server (504)

Server Error: an issue with an origin or Akamai server (501, 502, 503, 504)

Client Abort: the client canceled the connection before receiving any content (000)

Other: any other HTTP response code not included above