We have a standard L2TP LNS configuration using Cisco's VPDN. Although everything is working, there's an issue that we've noted - UDP traffic on port 1701 between LAC and LNS is huge.
Compared to bandwidth consumed by users (cumulative tx/rx rate on virtual-access), this UDP traffic is almost equal - it doubles link consumption?! Is this normal, or we're missing something?
Any feedback would be appreciated.