Balance One, firmware 7.0.0, WAN/Network1/Connection Settings, the terms used are “Upload Bandwidth” and “Download Bandwidth” which make sense and most users can understand. Download = from ISP to you, Upload = from you to ISP.
However, on Outbound Policy when you edit a rule and click the “Help” (?) icon on Algorithm, the description says:
Least Used - Traffic will be routed through the healthy WAN connection that is selected in the field Connection and has the most available downlink bandwidth
This confuses me. Shouldn’t this say upload bandwidth since this is the setting for Outbound policy?
Or am I completely misunderstanding how Least Used works?
This is by design and is worded correctly. The outbound policy rule dictates how the traffic will be routed for a given session.
In order to determine the Least Used WAN connection we look at the real-time downlink capacity of all the connections and this is compared against the value you enter under the Download Bandwidth setting of the WAN links.
If you are going to be using this rule it is very important you set the correct speeds on the WAN settings page. This also applies to the Overflow algorithm as well.
For Outbound policy, it would seem that the most important thing for the router to pay attention to would be the Outbound Bandwidth (e.g. data leaving the router going to the cloud, what most people would call their “Upload” bandwidth).
Why would the “Least Used” or “Overflow” algorithms pay attention to the Incoming (aka “Download”) bandwidth?
You could also look at it like “99% of requests yield a response”. Most all networking is from the standpoint of consumer (client) and Producer (server). Typically the traffic is small query yields infinitely large results. Most bandwith shaping utilities focus on inbound flows that originate from an outbound request. This is why many subscriber links are lopsided (huge down / much smaller up). From that perspective - if I wanted to route a file download for Xbox live to the WAN link that is under the least amount of utilization - I would route it to the link with the highest download capacity by routing the outbound (SYN) packet through it. That triggers the incoming data to come through the fastest available link.
Unless you are running a ton of servers, your outbound rules are more for managing inbound traffic to the desired link. All traffic will respond to the WAN that originated the request. Typically, if you are running a bunch of services, you would use different DNS entries per WAN IP to balance traffic or isolate data flows.