The <4U size was meant as approximation of the expected market segment and the number itself came to me as “anything smaller than smallest 6k5”. In fact I just

The <4U size was meant as approximation of the expected market segment and the number itself came to me as “anything smaller than smallest 6k5”. In fact I just wanted to avoid the “entry-level” moniker. Another question is router vs. switch. And as for routers I'm still somewhat discontent with Cisco's marketing wrt. CEF which on “small-ish” Cisco platforms simply meant implementing routing logic in software in exactly same way as any OS with BSD derived IP stack instead of the original IOS braindead implementation. And as for hardware redundancy: I have large amount of stories that somewhat discredit the idea of low level redundancy (ie. you remove the SPOF and replace it with another failure point in the fail over logic that is guaranteed to fail in ways that nobody understands). And two of these stories with largest impact involve Cisco hardware.