[dns-operations] difference between several NS with several glue

[han feng]

For a zone(like  example.com) owner, what’s the difference between these following two configurations:

example.com.	86400	NS 	a.example.net.
example.com.	86400 	NS 	b.example.net.
example.com. 	86400 	NS 	c.example.net.

a.example.net. 3600 A  1.1.1.1
b.example.net. 3600 A  2.2.2.2
c.example.net. 3600 A  3.3.3.3

and

example.com.	86400	NS 	a.example.net.

a.example.net. 3600 A  1.1.1.1
a.example.net. 3600 A  2.2.2.2
a.example.net. 3600 A  3.3.3.3


Since all the name servers are in example.net zone, these two configure both specify three name servers
for example.com zone and will be affected if example.net name server failed.  And the latter configuration 
will generate smaller package. But the first configuration seems more common, so what’s the benefit?

Thanks.