Data Usage Docs in Android 4.0 for Systems Integrators.
Change-Id: I65606843ebe5396037c43cf633a0b8c536bfaa1d
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+<!--
+ Copyright 2012 The Android Open Source Project
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+-->
+
+Tethering involves forwarding of traffic from one network interface to
+another using `iptables` forwarding rules. The framework periodically
+records tethering statistics between any interface pairs returned by
+`ConnectivityService.getTetheredIfacePairs()`.