Knowledge Base

Counters in Audit files

Two new counters have been added in Audit files (from 8.10 SP4 and 8.2)

Flow of byte sent and received from LAN manager:

LAN Send byte 0         13.8 __ base 10
7476.7 __ 10/09 15:26:29
27.6 __ 10/09 15:28:08
27.6 __ 10/09 15:28:52
27.6 __ 10/09 15:29:14
27.6 __ 10/09 15:29:47

LAN Rcv byte 0      49888.6 __ base 10
97833.2 __ 10/09 15:48:29
97391.4 __ 10/09 15:52:31
96719.2 __ 10/09 15:52:42
96627.7 __ 10/09 15:54:10
96390.6 __ 10/09 15:42:15

• LAN Send byte – The number of byte sent by the local station toward all remote stations
• LAN Rcv byte – The number of bytes received by the local station from all remote stations

Using these counters one can know the communication flow from a station (In and out)

Estimation of bandwidth

To estimate the network load in nominal mode (i.e. when all the stations are connected and all the subscriptions are done) you must calculate 100 bytes for each variable change transmitted.

Example 1:

1 server and 5 clients
200 variables changing per second, the flow on the network will be:
200 * 5*100 = 100 000 bytes per second or 800 Kbits /s

Counters in audit will be:
On the server: LAN Send byte = 100 000
On the clients: LAN Rcv byte = 20 000

Example 2:

2 redundant servers single active and 5 clients
200 variables changing per second, the flow on the network will be:

For the active server:    200 * 6 * 100 = 120 000 bytes/s.
For the passive server: 200 * 5 * 100 = 100 000 bytes/s (Clients are pre-subscribed and pre-refreshed by the passive server)
Total : 220 000 bytes/s or 1,76 Mbits/s

On the active server:       LAN Send byte  =  120 000
On the passive server:     LAN Send byte  =  100 000
On the clients:               LAN Rcv byte     =  40 000