With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
bstunPortDefaultPeerSerial
Cisco Blocked Serial Tunneling Port Default Peer Serial
1.3.6.1.4.1.9.9.35.1.3.1.1.4
If bstunRouteType is serial then this is the serial interface index of the point-to-point link to the remote partner; if bstunRouteType is serialDirect then the partner is in the local BSTUN. if bstunRouteType is ip then this field is 0.
Back to CISCO-BSTUN-MIB MIB page.
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