On Thu, Dec 29, 2016 at 10:05 AM, Randy Bush <ra...@psg.com> wrote: > > I apparently wasn't very clear. In the layered approach to multiple > > vendors, you would (obviously) choose your layer definitions to avoid > > such delicate interdependence. > > can you describe in useful detail your operational experience doing > this?
I'll certainly try. As one hopefully fairly clear example; at a large (US-nation-wide) metro Ethernet provider, we standardized as follows: L3 devices (aka core, customer edge, and Internet/peering edge routers) were all from Vendor A - These devices spoke OSPF, BGP, and RSVP with each other. L2 devices (aka metro ring switches) were all from Vendor B - These devices spoke STP with each other. L1 devices (aka optical transport) were all from Vendors C or D (individual markets got to choose which, but they could only have one each) - These devices inter-operated with each other at the optical layer. Basic network security was handled by devices from Vendor E - These devices collected netflow data and flagged alerts DNS was handled by software from another vendor on servers from yet another vendor, etc... Is that enough detail to be useful?
