Telephony best practices for IP (posted 2002-06-28)
In March, the NANOG list focussed some of its attention on efforts of the telephony world to com up with "best practices" about packet networks/the internet. (Network Reliability and Interoperability Council publications) In meeting minutes, 100% of the carriers reported to abide by these best practices, which include firewalling routers and DNS servers.
There were discussions about the merits of filtering/firewalling at OC-192 (10 Gbps) speeds (which, depending on your definition of "firewall" may be impossible to do) and about out-of-band versus in-band management. The former is always used in the telephony world, the latter often in IP. The main problem with out of band management is that the management network may be unavailable when the network is in critical need of being "managed". Also, many vendors do not support a clear separation between production and for-management interfaces.