SRS Timestamp

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I would post this to the mailing list [email protected], but it
appers that list is deprecated in spite of being listed at
http://www.libsrs2.org/support.html .

Please forgive me if this has been discussed before, but I did some
searching
and didn't find anything appropriate.

In the paper http://www.libsrs2.org/srs/srs.pdf

  The resolution is one day, and it is a 10 bit number stored as 2 base32
characters.
  The timestamp is computed as unix time / (60 * 60 * 24)  mod 2 ^ 10 .

  This gives 1024 possible timestamps, with approximately a 3.5 year cycle
before a
  timestamp becomes valid again.

And on the wikipedia
  http://en.wikipedia.org/wiki/Sender_Rewriting_Scheme


   - *The timestamp* (TT) has a one-day resolution in order to make the
   address invalid after a few days. Computed as unix
time<http://en.wikipedia.org/wiki/Unix_time>
   =E2=81=84(60*60*24) mod 210, it can be stored as a two
base32<http://en.wikipedia.org/wiki/Base32> characters,
   with a recycling period of about 3.5 years.


So, wouldn't the cycle time be
  - 2^10 days or
  - 1024 days or
  - (1024 / 365) years or
  - 2.8 years?

I don't understand where 3.5 years come from.

Dale W Moore



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<div dir=3D"ltr">I would post this to the mailing list <a href=3D"mailto:sr=
[email protected]">[email protected]</a>, but it appers that list=
 is deprecated in spite of being listed at=C2=A0<a href=3D"http://www.libsr=
s2.org/support.html">http://www.libsrs2.org/support.html</a> .<div>
<br></div><div>Please forgive me if this has been discussed before, but I d=
id some searching</div><div>and didn&#39;t find anything appropriate.<br><d=
iv><br></div><div>In the paper=C2=A0<a href=3D"http://www.libsrs2.org/srs/s=
rs.pdf">http://www.libsrs2.org/srs/srs.pdf</a></div>
<div><br></div><div><div>=C2=A0 The resolution is one day, and it is a 10 b=
it number stored as 2 base32 characters.</div><div>=C2=A0 The timestamp is =
computed as unix time / (60 * 60 * 24) =C2=A0mod 2 ^ 10 .</div><div><br></d=
iv><div>=C2=A0 This gives 1024 possible timestamps, with approximately a 3.=
5 year cycle before a</div>
<div>=C2=A0 timestamp becomes valid again.</div></div><div><br></div><div>A=
nd on the wikipedia</div><div>=C2=A0 <a href=3D"http://en.wikipedia.org/wik=
i/Sender_Rewriting_Scheme">http://en.wikipedia.org/wiki/Sender_Rewriting_Sc=
heme</a></div>
<div><br></div><div><ul style=3D"line-height:22.399999618530273px;margin:0.=
3em 0px 0px 1.6em;padding:0px;color:rgb(37,37,37);font-family:sans-serif;fo=
nt-size:14px"><li style=3D"margin-bottom:0.1em"><b>The timestamp</b>=C2=A0(=
TT) has a one-day resolution in order to make the address invalid after a f=
ew days. Computed as=C2=A0<span class=3D"" style=3D"font-family:&#39;Nimbus=
 Roman No9 L&#39;,&#39;Times New Roman&#39;,Times,serif;font-size:17px;whit=
e-space:nowrap"><span class=3D""><sup style=3D"line-height:1"><var><a href=
=3D"http://en.wikipedia.org/wiki/Unix_time" title=3D"Unix time" style=3D"te=
xt-decoration:none;color:rgb(11,0,128);background-image:none">unix time</a>=
</var></sup>=E2=81=84<sub style=3D"line-height:1">(60*60*24)</sub></span>=
=C2=A0mod 2<sup style=3D"line-height:1">10</sup></span>, it can be stored a=
s a two=C2=A0<a href=3D"http://en.wikipedia.org/wiki/Base32" title=3D"Base3=
2" style=3D"text-decoration:none;color:rgb(11,0,128);background-image:none"=
>base32</a>=C2=A0characters, with a recycling period of about 3.5 years. =
=C2=A0</li>
</ul><div><font color=3D"#252525" face=3D"sans-serif"><span style=3D"font-s=
ize:14px;line-height:22.399999618530273px"><br></span></font></div></div><d=
iv><font color=3D"#252525" face=3D"sans-serif"><span style=3D"font-size:14p=
x;line-height:22.399999618530273px">So, wouldn&#39;t the cycle time be=C2=
=A0</span></font></div>
<div><font color=3D"#252525" face=3D"sans-serif"><span style=3D"font-size:1=
4px;line-height:22.399999618530273px">=C2=A0 - 2^10 days or=C2=A0</span></f=
ont></div><div><font color=3D"#252525" face=3D"sans-serif"><span style=3D"f=
ont-size:14px;line-height:22.399999618530273px">=C2=A0 - 1024 days or =C2=
=A0</span></font></div>
<div><font color=3D"#252525" face=3D"sans-serif"><span style=3D"font-size:1=
4px;line-height:22.399999618530273px">=C2=A0 - (1024 / 365) years or</span>=
</font></div><div><font color=3D"#252525" face=3D"sans-serif"><span style=
=3D"font-size:14px;line-height:22.399999618530273px">=C2=A0 - 2.8 years? =
=C2=A0</span></font></div>
<div><font color=3D"#252525" face=3D"sans-serif"><span style=3D"font-size:1=
4px;line-height:22.399999618530273px"><br></span></font></div><div><font co=
lor=3D"#252525" face=3D"sans-serif"><span style=3D"font-size:14px;line-heig=
ht:22.399999618530273px">I don&#39;t understand where 3.5 years come from.<=
/span></font></div>
</div><div><font color=3D"#252525" face=3D"sans-serif"><span style=3D"font-=
size:14px;line-height:22.399999618530273px"><br></span></font></div><div><f=
ont color=3D"#252525" face=3D"sans-serif"><span style=3D"font-size:14px;lin=
e-height:22.399999618530273px">Dale W Moore</span></font></div>
<div><font color=3D"#252525" face=3D"sans-serif"><span style=3D"font-size:1=
4px;line-height:22.399999618530273px"><br></span></font></div></div>
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