Re: New link-type for Z-Wave serial interface

[Guy Harris <gharris () sonic net>]

On Jul 21, 2019, at 1:14 PM, Mikhail Gusarov <dottedmag () dottedmag net> wrote:

> That's right. Also there might be some garbage frames at the beginning of capture
> (basically, the contents of the current packet up to ACK/NAK/CAN/data).

So a "garbage frame" would be any frame that begins with a value other than 0x06, 0x15, 0x18, or 0x01?

Is there any reason for whatever capture mechanism produces these packets not to discard garbage frames rather than 
handing them to the libpcap caller (if this is implemented as a libpcap module) or writing them to a file (if this is 
implemented as a program that writes pcap or pcapng files)?

> Now that I think about it, in a very rare case it is possible to not be able to synchronize at all:
> if a SOF byte is encountered inside the data frame, then the next byte will be interpreted as a length,

If by "SOF byte" you mean "byte with the value 0x01", then an SOF byte will be encountered inside every frame of type 
Response, so it seems pretty clear that a data-frame-reading algorithm of "read and accumulate bytes until you see an 
0x01" won't work.
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