Broadcom, Metanoia, and Sckipio chips communicate. For more than a decade, the industry has come together at the University of New Hampshire to confirm chips work well together. No standard - even the 300 pages of G.fast - covers everything. No company is likely to include everything in those 300 pages. But they have to work well in the field. A gateway with a Metanoia chip needs to connect robustly with a DSLAM with a Broadcom chip. Customers hate to be locked into a single source so demand vendors solve the problems.
Live at the Broadband World Forum, the major vendors connected their gear and a Telebyte tester (pictured.) They've been meeting regularly at the new lab at UNH; all report progress but there's still much work to do. Additional plugfests were scheduled for November and January.
Lincoln Lavoie of UNH is The Man on DSL interoperability.