Why did a wrong VPI setting still work?

[Brian_G]

Discovered something odd on a router recently, VCI was set right to 8 but the VPI was wrong - on the default 32 instead of 35 for S.A. - and yet it worked.

Based on some googling...

Virtual Path Identifier abbreviated as VPI is a data communication identifier that uniquely identifies a network path for an asynchronous transfer mode (ATM) cell packet to reach its destination node. It is a method of sending data in small data packs.

VPI is useful to reduce the switching table for some Virtual Circuits which have common path.

...it sounds like it may just slow things down, little else. True?

Also, there was a problem with some Showmax streaming usage being dropped after about 80% done which now seems to have disappeared. TIA for any insight.