On 2/22/19 11:27 AM, b...@theworld.com wrote: > I don't know the high-water mark for the number of IMPs or more > specifically how many existed on the NCP->TCP flag day but I'm pretty > sure the theoretical maximum was 256 tho no doubt someone had a way to > extend that. But, w/o extensive changes, 256, probably 254, not sure 0 > or 255 could be an IMP number, whatever!
There was no node 0 or 255. So the number of nodes was capped at 254. For each node, there were subnodes so that multiple computers at each location could be addressed. It wasn't a full 8-bit field.