Remove domain-sharding

[prushforth]

Background

In the past, Web browsers limited the number of simultaneous TCP/IP connections that were permitted to a Web page. In consequence, some domain mapping services that serve tiles implemented a workaround, known as domain sharding. This technique created virtual domain hosts for serving tiles from virtual hosts, each of which was considered independent for the purposes of browser connection limits. For example, a single tile cache might be served from three virtual hosts https://a.example.com/, https://b.example.com/ https://c.example.com/ each of which was allowed the maximum number of TCP/IP connections from a Web page. In this way, request parallelism could be maximized, potentially resulting in time saved for map loads.

Requirement

In the Layer and Layer Group “Publishing > MapML Settings” administration panel, remove the “Sharding Config” user interface to enable domain sharding and its options. Remove the supporting code from the MapML extension model. Domain sharding is no longer required and is no longer considered part of the MapML proposal, having been superseded by the abilities of HTTP2 protocol.