TTL from SOA is smaller than TTL from local DNS!

[Vishwas]

Hi,

Please take a look at the following table. There are 5 columns.

column-1  --  domain name
column-2  --  domain's authoritative DNS
column-3  --  TTL returned by the authoritative DNS for its entries
column-4  --  TTL returned by the local DNS for corresponding entry
column-5  --  difference between the TTLs


domain  ---  domain-DNS ---  TTL-from-authority  ---
TTL-from-local-DNS  ---  TTL-diff

yahoo.com       ns5.yahoo.com   172800  83747   89053
msn.com         ns2.msft.net    172800  52158   120642
google.com      ns4.google.com  345600  158352  187248
youtube.com     dns2.sjl.youtube.com    3600    141492  -137892



Look at the fourth row, the difference between the TTLs is negative!
Under what circumstances the difference between the TTLs should be
negative?


-- 
Best Regards,
Vishwas.
ivishwas.googlepages.com

"So long as you rob Peter to pay Paul, you'll have Paul's support." -- Anonymous