User's Manual

nano3G AP Installation Manual Troubleshooting
N3G_INST_300 v14.0 for N3G_2.85 © ip.access Limited 2012 Page 74
8.4 Options for a Low Bandwidth Connection
8.4.1 N User Configuration
It may be useful to reduce the number of active UEs on an AP when an AP has a backhaul
link with limited bandwidth. N-User Configuration allows for a reduction in the maximum
number of active UEs on a nano3G AP by controlling how many CELL_DCH users are
allowed on an AP.The maxNumCellDchEues attribute reports the hardware capability of an
AP.
Each reduction in max users will reduce the max requirement for CS by 60Kbps in DL and
18Kbps in UL.
There is no effect if the override value in maxNumCellDchUesOverride is equal or greater
than the hardware capability.
1) Log into the NOS Client and find the AP. The user ID must have Full Access rights
to the AP.
Hence find, Root > APs > BSMIS APs Per AC > Site > relevant AP.
2) Select Admission Control Package from the Navigation Pane.
3) Select the attribute maxNumCellDchUesOverride and set to the relevant value.
4) Click Apply to save changes.
8.4.2 Dynamic Backhaul Management (DBM)
The DBM feature addresses the need to make optimal usage of backhaul bandwidth in
scenarios where backhaul bandwidth is limited.
Note: Where a nano3G AP is deployed without IPsec enabled and the Backhaul ISP or other
routers between the nano3G AC and the AP are aeroing out DSCP marking applied by the
AC on the downlink, then the DBM feature on the DL should NOT be enabled. This only
affects the DL as the AP does not control DL DSCP marking.
Note: On the UL the AP is the source of the packets. Hence, prioritisation and bandwidth limiting
occurs before DSCP marks are zeroed out by routers or ISPs.
Note: Where APs use IPsec, the AP will inspect the inner packet, which should not have its DSCP
mark removed, and should continue to function with the DBM DL limit applied.
To set a limit on total AP bandwidth usage of the backhaul and prioritise CS voice traffic to
ensure that voice quality is maintained, do the following: