> just want the order maintained within those conceptual streams and not the whole TCP connection, but routers don't know that.
seems to imply that routers inspect TCP streams and maintain order. I'm not aware of any routers that actually do anything like this, and things need to keep working just fine if different packets in the stream take different paths. Certainly in theory, IP routers don't have do inspect packets any deeper than the IP headers, if they're not doing NAT / filtering / shaping. The protocols are designed to strictly minimize the minimum amount of state kept in the routers.
As far as I'm aware, only the kernel (or userspace) TCP stack makes much effort at all to maintain packet order (other than routers generally using FIFOs).
> just want the order maintained within those conceptual streams and not the whole TCP connection, but routers don't know that.
seems to imply that routers inspect TCP streams and maintain order. I'm not aware of any routers that actually do anything like this, and things need to keep working just fine if different packets in the stream take different paths. Certainly in theory, IP routers don't have do inspect packets any deeper than the IP headers, if they're not doing NAT / filtering / shaping. The protocols are designed to strictly minimize the minimum amount of state kept in the routers.
As far as I'm aware, only the kernel (or userspace) TCP stack makes much effort at all to maintain packet order (other than routers generally using FIFOs).