RuggedCom RuggedRouter RX1100 - Manual (Page 201)

20. Traffic Prioritization
Revision 1.14.3 201 RX1000/RX1100™
If you delete a queue referenced by filters, the filters will be adjusted to use the next lowest queue.
20.2.2.2. Prioritization Filters
Figure 20.4. Prioritization Filter Configuration
This menu allows you to edit and delete traffic filters.
The Source IP/Netmask and Dest IP/Netmask fields specify the IP addresses and masks used to
match an outgoing packet. Use 0.0.0.0/0 to generate an “all packets” match.
The Source Port and Dest Port fields specify the port numbers used to match an outgoing packet.
You may specify either a raw number or a mnemonic as specified in the /etc/services file. This setting
matches both udp and tcp ports, unless the Protocol field specifies udp or tcp.
The Protocol field specifies a protocol to match against, currently either tcp, udp, icmp, ospf, vrrp
or ipsec.
The Target Queue field selects one of the available priority queues.
20.2.2.3. Prioritization Transmit Queue Length
The WAN protocols supplied by the RuggedRouter rely upon transmit queues to ensure their
efficiency. Even as a packet is starting to be transmitted, other packets can be lining up behind it.
Normally there is only one queue, the transmit queue, and packets are transmitted from it in the order
in which they arrived.
The transmit queue is a means of enhancing performance.
Prioritization favors some packets over others by transmitting them with preference.
Prioritization works by establishing queues at the required priority levels filling the transmit queue with
them in priority order. The aim of establishing low latency for certain traffic is foiled when transmit
queue lengths are large because multiple low priority packets may have queued before a high priority
packet arrives at the router.
RuggedCom recommends that the transmit queue length be left at its minimum default value of 1.
Higher values, however, may strike a balance between latency an performance.