Measures reported by CbrLinkStatsTest
In order to optimize bandwidth usage, minimize congestions, and maximize the speed of WAN and LAN links, administrators need to define the WAN and LAN links requiring traffic acceleration in the Citrix Branch Repeater, set the bandwidth limit for each of the links for receiving/sending data, and associate each link with traffic shaping policies. But, once the configuration is complete, how can administrators test the correctness of the configuration? For this, administrators can use the CbrLinkStatsTest test.
For each WAN and LAN link configured in the branch repeater, this test reports real-time metrics of the volume of traffic handled by the link and packet drops over the link. This way, the test reveals those links that are candidates for fine-tuning, owing to their low throughput despite the traffic shaping and acceleration rules that apply to them.
The measures made by this test are as follows:
| Measurement |
Description |
Measurement Unit |
Interpretation |
| Sent_Volume |
Indicates the rate at which data was sent over this link. |
KB/Sec |
Any attempt made to send or receive traffic faster than the link throughput can result in congestion. Therefore, the branch repeater should make sure that just about enough data is sent and received over application links to prevent congestion and optimize throughput.
If the values of these measures exceed or are dangerously close to the bandwidth limit of the link, it signals a potential congestion or slowdown of traffic over the link. It also indicates that you may have to reconfigure the branch repeater with more robust QoS and compression rules to prevent such unpleasant eventualities. |
| Received_Volume |
Indicates the rate at which data was received over this application link. |
KB/Sec |
| Sent_Packets |
Indicates the number of packets transmitted over this link. |
Number |
Any attempt made to send or receive traffic faster than the link throughput can result in congestion. Therefore, the branch repeater should make sure that just about enough data packets are sent and received over application links to prevent congestion and maximize throughput.
If the values of these measures exceed or are dangerously close to the maximum number of data packets that the link can handle, it signals a potential congestion or slowdown of traffic over the link. It also indicates that you may have to reconfigure the branch repeater with more robust QoS and compression rules to prevent such unpleasant eventualities. |
| Received_Packets |
Indicates the number of packets received over this link. |
Number |
| Dropped_Sent_Volume |
Indicates the rate of traffic not sent over this link due to QoS threshold settings. |
KB/Sec |
QoS (quality-of-service) is a set of policies and priorities assigned to the application traffic prioritized under traffic shaping policies in BR devices. A QoS threshold allows a sender to deliver only as much data as the branch repeater allows it to send, and this data is placed on the link at exactly the right rate to keep the link full but not overflowing. By eliminating excess data, the branch repeater is not forced to discard it. Without the branch repeater, the dropped data would have to be sent again, causing delay.
A high value for these measures could therefore indicate one of the following:
- The link bandwidth is low and hence the branch repeater has been rightly configured with a QoS threshold that allows only limited data to be sent/received over that link; this excludes a lot of data from transmissions/receptions and maximizes the responsiveness of the link;
- The branch repeater has been misconfigured with a QoS threshold that forces the link to send/receive much less data than what it can handle; this causes a lot of data to be unnecessarily dropped from transmissions/receptions, affecting the quality-of-experience in the process. In this case, you may have to fine-tune the QoS policy.
|
| Dropped_Received_Volume |
Indicates the rate of traffic not received over this due to QoS threshold settings. |
KB/Sec |
| Dropped_Sent_Packets |
Indicates the number of packets not sent over this link due to QoS threshold settings. |
Number |
QoS (quality-of-service) is a set of policies and priorities assigned to the application traffic prioritized under traffic shaping policies in BR devices. A QoS threshold allows a sender to deliver only as much data as the branch repeater allows it to send, and this data is placed on the link at exactly the right rate to keep the link full but not overflowing. By eliminating excess data, the branch repeater is not forced to discard it. Without the branch repeater, the dropped data would have to be sent again, causing delay.
A high value for these measures could therefore indicate one of the following:
- The link bandwidth is low and hence the branch repeater has been rightly configured with a QoS threshold that allows only limited number of packets to be sent/received over that link; this excludes a lot of packets from transmissions/receptions and maximizes the responsiveness of the link;
- The branch repeater has been misconfigured with a QoS threshold that forces the link to send/receive much less data than what it can handle; this causes a lot of packets to be unnecessarily dropped from transmissions/receptions, affecting the quality-of-experience in the process. In this case, you may have to fine-tune the QoS policy.
|
| Dropped_Received_Packets |
Indicates the number of packets not received over this link due to QoS threshold settings. |
Number |
|