"Airy R. Bean" wrote in message
...
ISTR that the Plesiochronous Digital Hierarchy of BT ran
via a single master oscillator.


Plesiochronous refers to a system with signals having a common data rate
(within defined limits) which are sychronised to different clocks. Sometimes
referred tp as 'nearly synchronised'.

ie no 'master clock', with or without a remontoire ;-).

In a plesiochronous switched data system, the signals may be synchronised
at a given instant permitting switching withourt loss of frames but, when
the signals drift apart, the switches must compensate by a process known as
'frame slip'- not required in a system synchronised to a master oscillator.

I've no doubt you will respond with 'rubbish' etc. but I invite the others
on the NG to look up the term and decide who is correct.



--
73
Brian
G8OSN
www.g8osn.org.uk
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