Military Communications and Information Technology: A Trusted ...

174 Military Communications and Information Technology...
Figure 8. Technical profile repositories and user systems which will use these technical profiles
Walkthrough: When technical profile mechanisms are not enabled and when
traffic conditions in TNS 4 are adverse, it takes an unacceptable time for host B to
download a HTML page from host A.
When technical profile mechanisms are enabled, measurements permanently
conducted in all TNSs allow the detection of a degradation of transport conditions
(in this case a high packet loss rate in TNS 4), and this situation is reflected
in the relevant technical profiles.
Whenever it receives a request from host B, host A first determines which
TNSs will be traversed by the data flow it is about to send to the Web client. Then
it fetches the technical profiles of TNSs 1 and 4 and composes them to find out that
the path will be affected by a high packet loss rate.
Knowing this information, it decides to send to host B a HTML page with
skimmed contents (i.e. with lower-resolution pictures). The time it takes for host B
to download the page returns to an acceptable value.
At the end of this test, the best compromise has been automatically discovered
to ensure end-to-end quality of service in the presence of degraded transport
conditions detected through measurements.
Prerequisites and special requirements: Interface MI 2, as described in section
III of this article, is required to convey to the colored domain information
pertinent to the black networks.