Network Monitoring Software

Hello all. I’m looking for various Network Monitoring software that has alphanumeric paging capabilities. What’sUp Gold looks very promising but I need more programs to compare in order to get a good idea of other possible solutions. I’d like SNMP(both 1 and 2), auto-discovery, alphanumeric paging, and configurable poll rates per device or subnet. Extras would be RMON, SMTP alerting, SYSLogging, and a Web interface for reports (but not crucial).

Any ideas?

Thanks!