With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
pnniDTLEntry
pnni DTL Entry
1.3.6.1.4.1.353.5.4.1.1.19.3.1
A segment of a DTL stack. The complete DTL stack is formed by traversing the rows of the table for which the pnniDTLIndex is the same. Level transitions are indicated using the pnniDLTLinkType column.
Back to PNNI-MIB MIB page.
IPHost Network monitor allows you to monitor pnniDTLEntry on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco firewalls right now.