PPPoE question.
Brian Candler
B.Candler at pobox.com
Wed Apr 12 15:13:42 UTC 2006
On Wed, Apr 12, 2006 at 10:59:52PM +0800, fooler wrote:
> >>set speed sync
> >
> >And how does that change the pppoe ethernet frames?
>
> nothing change and still the same... ethernet frames are at layer 2 while
> synchronization (either asynchronous or synchronous) is at layer 1...
> synchronous is much better than asynchronous for ethernet links...
Then I think you have a misunderstanding. Ethernet frames are *always*
synchronous. There are no 'start' and 'stop' bits in ethernet, only frame
delimiters.
The sync/async difference only has meaning for serial links (e.g. where
layer 1 is RS232 / V24)
PPP frames carried inside ethernet (i.e. pppoe) are therefore also carried
using synchronous encoding, since ethernet is synchronous.
Brian.
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