On May 27, 2014, at 3:17 PM, Bob Armstrong <bob at jfcl.com> wrote: in Phase IV the hello timer value is sent in the hello message and that value times 3 (or 2) is used for the listen timer That would explain why having LEGATO send hello messages more often doesn't make any difference If you send hellos more often, you time out sooner; either way, you time out if you lose 3 hellos in a row (or, probably just barely, if you lose two in a row). The assumption is that no LAN is that badly broken. The way to run DECnet over a flaky long distance network is to use point to point mode with a data link layer that deals with packet loss. DDCMP is an example of such a data link layer; X.25 is also (after a fashion). That s what the DECnet design intended. paul