Enlarge / You might need more of this stuff if you want to use Chrome's new Site Isolation mode. Well, not this stuff exactly; it's RAM from a very obsolete VAX computer. (credit: Kevin Stanchfield)
To further increase its enterprise appeal, Chrome 63—which hit the browser's stable release channel yesterday—includes a couple of new security enhancements aimed particularly at the corporate market.
The first of these is site isolation, an even stricter version of the multiple process model that Chrome has used since its introduction. Chrome uses multiple processes for several security and stability reasons. On the stability front, the model means that even if a single tab crashes, other tabs (and the browser itself) are unaffected. On the security front, the use of multiple processes makes it much harder for malicious code from one site to steal secrets (such as passwords typed into forms) of another.
Chrome's default model is, approximately, to use one process per tab. This more or less ensures that unrelated sites are kept in separate processes, but there are nuances to this set-up. Pages share a process if they are related through, for example, one opening another with JavaScript or iframes embedding (wherein one page is included as content within another page). Over the course of a single browsing session, one tab may be used to visit multiple different domains; they'll all potentially be opened within a single process. On top of this, if there are already too many Chrome processes running, Chrome will start opening new pages within existing processes, resulting in even unrelated pages sharing a process.