The setup we use for VOIP QOS is:
1) Create a parent queue to match the LAN interface (or the LAN network, if I know that instead). Set this queue up with the customer package limit for download & upload -- if you leave it unlimited, there will still be short hiccups of bad voice quality when a burst of data traffic starts, until the queue learns what the upstream limit is. The drawback is, of course, if the upstream package limit is ever increased, you'll have to remember to edit your parent queue as well. Change the queue type from default-small to default.
2) Add a queue for the voice traffic. Most of the time, I match the internal IPs of the phones, but you could also have the "target" set to the whole LAN network and add a destination for the network of the external SIP servers (If they don't fit into a single network, you're going to have to packet mark instead). I set max-limit and limit-at of (100k * number of simultaneous calls) for upload and download on this queue, priority 1, with a parent of the above. Change the queue type from default-small to default.
3) Add a queue for all other traffic. Most of the time, I set this to match 0.0.0.0/0 -- as long as your parent is matching specifically from the LAN side, this will work, though it may be a better practice to only match on the internal network. You can leave this unlimited if you want, but I usually set it to the same max-limits as the parent, so I can see traffic on the Traffic tab. Change the queue type from default-small to default.
So, in your network, that might look something like:
/queue simple add max-limit=1100k/5500k name="Master Parent" queue=default/default target=192.168.1.0/24 add limit-at=500k/500k max-limit=500k/500k name="Phone Traffic - 5 calls" parent="Master Parent" target=192.168.1.0/24 dst=172.16.16.0/29 add max-limit=1100k/5500k name="All Internet Traffic" parent="Master Parent" queue=default/default target=192.168.1.0/24
如果公众IPs的SIP服务器并不在ir own simple network (so that Destination won't work for you), then you'll have to either set multiple targets for all the internal phone IPs (if those are static), or use an address list and packet-marks to identify connections to or from the SIP servers and match the packet-mark into the simple queue.