I too have seen this problem and can verify it does still exist in
1.4.3.  Until
now, my inkling was that it was something specific to my system/ISP and
ignored it,
but seeing your message makes me wonder again. I have a feeling people
here will
tell you to submit a PR for this.

//Jesse Off

"John F. Woods" wrote:
> 
> I'm seeing an odd problem with pppd on my 1.4.1 i386 system, and I'm
> wondering if anyone else has ever seen this problem, or if it has been
> fixed at some point.
> 
> After pppd has run for a while, it sometimes declares an LCP ECHO link
> failure ("Serial link appears to be disconnected.") and hangs up and
> redials (I have a 24x7 modem link).  About 30 seconds later, it
> declares the link dead AGAIN ("Serial link appears to be
> disconnected.") and hangs up and redials AGAIN, over and over again
> until I kill the pppd daemon and re-start it.  I have the LCP echo
> frequency set to 30 seconds with a failure count of 6 -- so 30 seconds
> should not be enough time to discover a failed link.
> 
> So, is this a known problem that has been fixed for ages (and I just
> need to get off my lazy duff and update my system), or is this a
> mystery problem that plagues only my system?
> 
> (You know, it's amazing how well an IP link can actually work when
> it's operational in only 15 second bursts every 30 seconds...)