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Re: [DNA] DNAO format revision?

Hi Greg,

We can have different formats for the same.
but everything comes with their own advantages and limitations.

Below I suggested one more varients. Let me know your opinion on the same.

But I also perfer the Varient 1 you proposed as
it is more simple and no problem of 16 bytes representation
of prefexes which are less than or equal to 64. Only problem it will waste 
some bytes.
But its ok, unless somebody comes up with some good solution.

Thanks and Regards,
Wable R. U.


Varient 3:

    0                   1                      2                      3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type         |       Length     |               Reserved 
|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Prefix Len 1  |     Resv      | R|               Reserved 
|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | 
|
   + 
+
   | 
|
   +                               Prefix 1 (128 bits) 
+
   | 
|
   + 
+
   | 
|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Prefix Len 2  |     Resv      | R|                Reserved 
|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | 
|
   +                                Prefix 2 (64bits) 
+
   | 
|
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Prefix Len 3  |     Resv      | R|                Reserved 
|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | 
|
   + 
+
   | 
|
   +                                Prefix 3 (64bits) 
+
   | 
|
   + 
+
   | 
|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                 Padding(32 Bit) 
|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Here the Prefix 1 is 128 bit R = 1.
Prefix 2 R =0.
Prefix 3 is 64 bit but still represented with the 16 byte so R=1.

Assuming the fact that most of the time the prefix length will be less than 
or equal to 64
we will be able to save at max 4 bytes per prefix. Alignment will be 4 
bytes.

Also here we have reserved field to convey more informations about the 
prefixes.
I agree there is no such need now and hence may be just place holders.