Add an example of how tracestate will be used

[tigrannajaryan]

trafficstars

This specification defines the details of how to construct, propagate and modify tracestate. However it contains no examples which would demonstrate how the tracestate is used eventually after it is propagated and arrives at some final destination. There are hints about it in 2.2 Solution but they are vague.

It would help significantly to show an example and use cases of how having the tracestate helps and how exactly the information stored in it is used eventually.

I can think of a couple simple use cases:

Use Case 1

1. Vendor UI may show the tracestate value as-is.
2. Another vendor's UI may allow manually searching for traces via vendor-specific value of corresponding tracestate entry. The end-user is expected to understand the format of tracestate and extract vendor-specific value manually.

Use Case 2

1. Vendor UI may understand and know how to decode and interpret tracestate value.
2. For entries in tracestate that correspond to traces in a different vendor show a hyperlink that points to the UI of a different vendor and the hyperlink correctly passes vendor-specific portion of tracestate as a search parameter. The end-user is not require to understand the format of tracestate, the integration and navigation between different vendors is automatic.

Question: are these valid use cases? Does this w3c group have different use cases in mind?

[danielkhan]

Should be done in the new structure - see #29