IPv4 address length technical design

William Herrin bill at herrin.us
Thu Oct 4 20:34:17 UTC 2012


On Thu, Oct 4, 2012 at 4:17 PM, Cutler James R
<james.cutler at consultant.com> wrote:
> On Oct 4, 2012, at 4:00 PM, William Herrin <bill at herrin.us> wrote:
>> On Wed, Oct 3, 2012 at 7:12 PM, Cutler James R
>> <james.cutler at consultant.com> wrote:
>> Or did you mean use DNS as it fits in the current system, which
>> doesn't actually satisfy (1) at all since the layer 4 protocols
>> continue to build the connection identity from the layer 3 network
>> identity instead of the external host/service identity.
>>
> Why does the connection identity have to include the host identifier.  Is that not a problem under the control of applications?

Nope. It's under the control of the layer 4 protocol, generally TCP or
UDP, and implemented at the OS level. For example, in TCP the
connection identity is composed of the source and destination IP
addresses and port numbers. Together, these 96 bits of information
comprise the unique identity of that TCP connection which the OS
matches to the socket number the application interacts with.

Regards,
Bill Herrin



-- 
William D. Herrin ................ herrin at dirtside.com  bill at herrin.us
3005 Crane Dr. ...................... Web: <http://bill.herrin.us/>
Falls Church, VA 22042-3004




More information about the NANOG mailing list