Dive Into Android Networking - Adding Ethernet Connectivity

The talk introduces you to Android connectivity layer: how it really works and what needs to be added as to make the system fully support traditional wired Ethernet technology.

Transcript

1. COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. 1 Benjamin Zores ELCE 2012 – 6th November 2012 – Barcelona, Spain Dive Into Android Networking: Adding Ethernet Connectivity
2. 2 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity About Me ALCATEL LUCENT ANDROID PLATFORM ARCHITECT • Expert and Evangelist on Open Source Software. • 9y experience on various multimedia/network embedded devices design. • From low-level BSP integration to global applicative software architecture. OPEN SOURCE PROJECT FOUNDER, LEADER AND/OR CONTRIBUTOR FOR: • OpenBricks Embedded Linux cross-build framework. • GeeXboX Embedded multimedia HTPC distribution. • uShare UPnP A/V and DLNA Media Server. • MPlayer Linux media player application. LINUX FOUNDATION CONFERENCES FORMER LINUX FOUNDATION’S EVENTS SPEAKER • ELC 2010 GeeXboX Enna: Embedded Media Center • ELC-E 2010 State of Multimedia in 2010 Embedded Linux Devices • ELC-E 2011 Linux Optimization Techniques: How Not to Be Slow ? • ABS 2012 Android Device Porting Walkthrough
3. 3 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Bibliographical References My Android bibles, from my Android mentors: Karim Yaghmour Marko Gargenta Followed by my own publications: « Discovering Android » Series of articles published in GNU/Linux Magazine France
4. 4 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Work Context • Designing an Enterprise Desktop IP Phone. • Differs heavily from usual Android devices: - Always connected, no battery - No Radio (GSM/CDMA). - No WiFi Station mode, AP only. - LAN through Ethernet PHY/Switch. - Always docked, no screen rotation. - No accelerometer, no GPS … - => Not a Smartphone
5. 5 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Give Unto Caesar What is Caesar's … Most of the work presented hereafter is courtesy of Fabien Brisset
6. 6 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. • Communicates with broadband processor for both voice and data. • Uses RIL and proprietary rild to interface with system. • Data connection is exported by Connectivity Manager through TYPE_MOBILE_* Dive Into Android Networking: Adding Ethernet Connectivity Radio Layer Interface
7. 7 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. • Communicates with BT chipset through BlueZ and libbluedroid. • Provides both audio and data management. • Data connection is exported by Connectivity Manager through TYPE_BLUETOOTH. • Interface with netd for tethering. Dive Into Android Networking: Adding Ethernet Connectivity Bluetooth Interface
8. 8 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. • Introduced with Ice Cream Sandwich for Near Field Communication. • Rely on NFC HAL. • Currently only support chips from NXP (PN544). • Uses Android Beam for P2P data exchange. • Doesn’t interface with Connectivity Service/Manager. Dive Into Android Networking: Adding Ethernet Connectivity NFC Interface
9. 9 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. • Rely on HAL for specific driver interface with JNI binding. • Data connection is exported by Connectivity Manager through TYPE_WIFI. • WiFi configuration is stored in file system and SQLite database. Dive Into Android Networking: Adding Ethernet Connectivity WiFi Station/AP/P2P Interface
10. 10 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. • Ethernet is supported through native Linux kernel drivers. • ifconfig / netcfg / ping commands work but remain at platform level. • Regular /etc/resolv.conf DNS is not supported due to Bionic host resolution. • Native system daemons (C/C++) support regular Linux networking API. • Java framework services and apps rely on Connectivity Manager and have no clue what Ethernet route/connection actually means. - Except for some apps (e.g. Browser, which relies on native implementation). • Barely no Android device features Ethernet - Except from some obscure Chinese tablets. • Ethernet connection type exists in ICS API. - But with no Connectivity Manager or Connectivity Service implementation. Dive Into Android Networking: Adding Ethernet Connectivity Android Ethernet Upstream Status
11. 11 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. • Enterprise Requirements: - Reliability: Ensuring data connection works in 100% cases for all possible applications. - HTTP(S) seamless proxy support for all applications. - Corporate firewalls prevents some services behavior (e.g. NTP). - Need to ensure everything stays behind the walls. - Ethernet 802.1x authentication. • Ethernet Connectivity Manager (ECM) Status - ECM patch has been done by Android-x86 team for netbooks. - Not 100% accurate or sufficient. Dive Into Android Networking: Adding Ethernet Connectivity Enterprise Requirements & ECM Status
12. 12 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. • Mismatch in implementation towards WiFi. • Rely on libnetutils dhcp implementation instead of DHCPCd. • Not completely binded on Connectivity Manager and Service. Dive Into Android Networking: Adding Ethernet Connectivity Ethernet Interface – ECM Patch Status
13. 13 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. • Changes in Android framework, Settings app and System UI. • Supports DHCP (ECM patch default) and Static IP (added) addressing. • Connection status is available in notification bar. Dive Into Android Networking: Adding Ethernet Connectivity Am I Connected or What ?
14. 14 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. • Register Ethernet Service - In framework's core/java/android/app/ContextImpl.java: registerService(ETHERNET_SERVICE, new ServiceFetcher() { public Object createService(ContextImpl ctx) { IBinder b = ServiceManager.getService(ETHERNET_SERVICE); IEthernetManager srv = IEthernetManager.Stub.asInterface(b); return new EthernetManager(srv, ctx.mMainThread.getHandler()); }}); • Letting Connectivity Service know about Ethernet: - In framework's services/java/com/android/server/ConnectivityService.java: [...] else if (networkType == ConnectivityManager.TYPE_ETHERNET) usedNetworkType = ConnectivityManager.TYPE_ETHERNET; Dive Into Android Networking: Adding Ethernet Connectivity ECM Patch Additions
15. 15 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. • Forcing default network preferences: - In framework's core/java/android/net/ConnectivityManager.java: - public static final int DEFAULT_NETWORK_PREFERENCE = TYPE_WIFI; + public static final int DEFAULT_NETWORK_PREFERENCE = TYPE_ETHERNET; Issue: Android public API is being modified and make update-api is required. - In framework's packages/SettingsProvider/res/values/defaults.xml: - <integer name="def_network_preference">1</integer> + <integer name="def_network_preference">9</integer> - In framework's services/java/com/android/server/EthernetService.java: - Settings.Secure.putString(cr, Settings.Secure.ETHERNET_IFNAME, DevName[0]); + Settings.Secure.putString(cr, Settings.Secure.ETHERNET_IFNAME, "eth0"); Dive Into Android Networking: Adding Ethernet Connectivity ECM Patch Additions
16. 16 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. And now, bugs and workarounds for various use cases: Making Ethernet 100% functional. Dive Into Android Networking: Adding Ethernet Connectivity
17. 17 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Connection Information Symptom: What is my Ethernet IP configuration or MAC address info ?
18. 18 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Connection Information – IP Address • In Settings's res/xml/device_info_status.xml: <Preference android:key="ethernet_ip_address" style="?android:attr/preferenceInformationStyle" android:title="@string/ethernet_advanced_ip_address_title" android:summary="@string/device_info_not_available" android:persistent="false" /> • In src/com/android/settings/deviceinfo/Status.java: private void setEthernetIpAddressStatus() { EthernetManager mgr = getSystemService(ETHERNET_SERVICE); EthernetDevInfo info = mgr.getSavedConfig(); Preference ip = findPreference("ethernet_ip_address"); String addr = null; if (info != null) { if (info.getIpAddress() != null) addr = info.getIpAddress(); else addr = SystemProperties.get("dhcp.eth0.ipaddress"); } ip.setSummary(!TextUtils.isEmpty(addr) ? Addr : getString(R.string.status_unavailable)); }
19. 19 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Connection Information – MAC Address • In framework's JNI code core/jni/android_net_ethernet.cpp: {"getInterfaceMacAddress", "()Ljava/lang/String;", (void *)android_net_ethernet_getInterfaceMacAddress}, [...] static jstring android_net_ethernet_getInterfaceMacAddress(JNIEnv *env, jobject clazz) { struct ifreq ifr; strcpy (ifr.ifr_name, "eth0"); strcpy (ifr.ifr_hwaddr.sa_data, ""); sock = socket (AF_INET, SOCK_STREAM, 0); ioctl (sock, SIOCGIFHWADDR, &ifr); ptr = (unsigned char *) ifr.ifr_hwaddr.sa_data; snprintf (buf, 64, "%02x:%02x:%02x:%02x:%02x:%02x", (ptr[0] & 0377), (ptr[1] & 0377), (ptr[2] & 0377), (ptr[3] & 0377), (ptr[4] & 0377), (ptr[5] & 0377)); return env->NewStringUTF(buf); }
20. 20 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Connection Information – MAC Address • In Settings' res/xml/device_info_status.xml: <Preference android:key="ethernet_mac_address" style="?android:attr/preferenceInformationStyle" android:title="@string/status_ethernet_mac_address" android:summary="@string/device_info_not_available" android:persistent="false" /> • In Settings’ src/com/android/settings/deviceinfo/Status.java: private void setEthernetMacAddress() { EthernetManager mgr = getSystemService(ETHERNET_SERVICE); EthernetDevInfo info = mgr.getSavedConfig(); Preference mac = findPreference("ethernet_mac_address"); String addr = info == null ? null : info.getMacAddress(); mac.setSummary(!TextUtils.isEmpty(addr) ? addr : getString(R.string.status_unavailable)); }
21. 21 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Android DNS Entry Management Symptom: DHCP can't seem to provide me with valid DNS entries. • Match Android process (AID) authorizations to update system properties in init's init/property_service.c: { "rw.", AID_SYSTEM, 0 }, { "net.", AID_DHCP, 0 }, • In DHCPCD's dhcpcd-hooks/20-dns.conf: for dnsaddr in ${new_domain_name_servers}; do setprop dhcp.${interface}.dns${count} ${dnsaddr} + setprop net.dns${count} ${dnsaddr} + setprop net.${interface}.dns${count} ${dnsaddr} count=$(($count + 1)) done • In framework's ethernet/java/android/net/ethernet/EthernetStateTracker.java: SystemProperties.set("net.dns1", mDhcpInfo.dns1); SystemProperties.set("net." + mInterfaceName + ".dns1", mDhcpInfo.dns1);
22. 22 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity HTTP(S) Proxy Symptom: I'm behind HTTP(S) proxy. I need my apps to seamlessly know about that !
23. 23 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity HTTP(S) Proxy • Overlay frameworks/base/core/res/res/values/config.xml: <string name="config_default_proxy_host" translatable="false">a.b.c.d</string> <integer name="config_default_proxy_port" translatable="false">8080</integer> • In framework’s services/java/com/android/server/ConnectivityService.java: String proxyHost = context.getResources().getString( com.android.internal.R.string.config_default_proxy_host); int proxyPort = context.getResources().getInteger( com.android.internal.R.integer.config_default_proxy_port); mGlobalProxy = new ProxyProperties(proxyHost, proxyPort, null); SystemProperties.set("net.http.proxy", proxyHost + ":" + proxyPort);
24. 24 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Custom NTP Server Symptom: I'm behind corporate firewall and can't do NTP request. My company provides its internal NTP server.
25. 25 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Custom NTP Server • Overlay frameworks/base/core/res/res/values/config.xml: <!-- Remote server that can provide NTP responses. --> <string translatable="false" name="config_ntpServer">a.b.c.d</string> <!-- Timeout to wait for NTP server response. --> <integer name="config_ntpTimeout">20000</integer> • In framework's core/java/android/util/NtpTrustedTime.java: - final String defaultServer = res.getString(com.android.internal.R.string.config_ntpServer); + String defaultServer = Settings.System.getString(resolver, Settings.System.NTP_SERVER); • In framework's services/java/com/android/server/NetworkTimeUpdateService.java: - Force NTP update on Ethernet state change: if (netInfo.getState() == NetworkInfo.State.CONNECTED && netInfo.getType() == ConnectivityManager.TYPE_ETHERNET) mHandler.obtainMessage(EVENT_ETHERNET_CONNECTED).sendToTarget(); [...] case EVENT_WIFI_CONNECTED: case EVENT_ETHERNET_CONNECTED: onPollNetworkTime(msg.what);
26. 26 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Custom NTP Server • In Settings's res/xml/date_time_prefs.xml: <EditTextPreference android:title="@string/ntp_server_time" android:key="ntp_server" android:singleLine="true" android:summary="192.168.1.1" android:inputType="textUri"/> • In Settings' src/com/android/settings/DateTimeSettings.java: EditTextPreference pref = findPreference("ntp_server"); String server = Settings.System.getString(getContentResolver(), Settings.System.NTP_SERVER); pref.setText(server); pref.setSummary(server);
27. 27 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Email Symptom: I can't download email attachments. • In src/com/android/email/AttachmentInfo.java: - if (networkType != ConnectivityManager.TYPE_WIFI) { + if ((networkType != ConnectivityManager.TYPE_WIFI) && (networkType != ConnectivityManager.TYPE_ETHERNET)) { • In src/com/android/email/service/AttachmentDownloadService.java: - if (ecm.getActiveNetworkType() != ConnectivityManager.TYPE_WIFI) { + if ((ecm.getActiveNetworkType() != ConnectivityManager.TYPE_WIFI) && (ecm.getActiveNetworkType() != ConnectivityManager.TYPE_ETHERNET)) {
28. 28 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Connectivity Route Symptom: I can't access to Google Play Store. The application just crash !
29. 29 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Connectivity Route Reverse engineering apps may help: • Dex2jar - Extracts usable classes.jar from APK archives. - See http://code.google.com/p/dex2jar/ • Java Decompiler (jd-gui) - See http://java.decompiler.free.fr/?q=jdgui
30. 30 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Connectivity Route • Many (certified?) apps assume that WiFi or mobile connection is always present. - We need to trick the system for Ethernet. - But this is truly an ugly hack. • In framework's services/java/com/android/server/ConnectivityService.java: public NetworkInfo getNetworkInfo(int networkType, int uid) { - return getNetworkInfo(networkType, uid); + switch (networkType) { + case ConnectivityManager.TYPE_MOBILE: + case ConnectivityManager.TYPE_WIFI: + case ConnectivityManager.TYPE_WIMAX: + networkType = ConnectivityManager.TYPE_ETHERNET; + break; + default: + break; + } + return getNetworkInfo(networkType, uid); } • Android shouldn't expose WiFi Manager API ! - Apps should always go through Connectivity Manager for all network information. • Limitations: - Connectivity Manager API can't configure default connection type (currently hardcoded). - Too few information on existing devices' connectivity states.
31. 31 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Download Provider Symptom: My browser works fine but I just can't download files. • In DownloadProvider's src/com/android/providers/downloads/DownloadInfo.java: - Add Ethernet connectivity support case ConnectivityManager.TYPE_ETHERNET: return DownloadManager.Request.NETWORK_ETHERNET; [...] if (networkType == ConnectivityManager.TYPE_ETHERNET) { return NETWORK_OK; // anything goes over ethernet }
32. 32 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Multimedia Streaming Symptom: My browser works fine but I can't play multimedia contents. • Force Chrome HTTP stack instead of Android HTTP stack. - By default, Stagefright can't bypass proxy (see frameworks/base/media/libstagefright/Android.mk) - Overlay in your device's device.mk file: HTTP := chrome • In framework's media/libstagefright/chromium_http/support.cpp: char value[PROPERTY_VALUE_MAX]; property_get("net.http.proxy", value, "Unknown"); net::ProxyConfigServiceAndroid cfg = new net::ProxyConfigServiceAndroid(); if (strcmp(value_proxy,"Unknown") != 0) { std::string proxy = value; cfg->UpdateProxySettings(proxy, ""); } set_proxy_service(net::ProxyService::CreateWithoutProxyResolver(cfg, net_log())); • In framework's services/java/com/android/server/ConnectivityService.java: - Optionally force proxy detection in proprietary OMX Codecs: SystemProperties.set("net.proxy", host + ":" + port); SystemProperties.set("rw.HTTP_PROXY", "http://" + host + ":" + port);
33. 33 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Phone / SIP VoIP Symptom: I can do VoIP SIP calls over WiFi but not over Ethernet. • Overlay frameworks/base/core/res/res/values/config.xml: <bool name="config_sip_ethernet">true</bool> • In framework's voip/java/android/net/sip/SipManager.java: public static boolean isSipEthernet(Context context) { return context.getResources().getBoolean(com.android.internal.R.bool.config_sip_ethernet); } • In framework's voip/java/com/android/server/sip/SipService.java: boolean mSipOnWifiOnly = SipManager.isSipWifiOnly(context); boolean mSipEthernet = SipManager.isSipEthernet(context); boolean connected = (info != null && info.isConnected() && ((!mSipOnWifiOnly || info.getType() == ConnectivityManager.TYPE_WIFI) || ( mSipEthernet && info.getType() == ConnectivityManager.TYPE_ETHERNET)); • In Phone's src/com/android/phone/SipCallOptionHandler.java: return ((ni.getType() == ConnectivityManager.TYPE_WIFI) || !SipManager.isSipWifiOnly(this)) || ((ni.getType() == ConnectivityManager.TYPE_ETHERNET) && SipManager.isSipEthernet(this));
34. 34 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Network Statistics Symptom: How much data did I use ? Where are my network statistics ?
35. 35 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Network Statistics • Overlay frameworks/base/core/res/res/values/config.xml: <!-- Set of NetworkInfo.getType() that reflect data usage. --> <integer-array translatable="false" name="config_data_usage_network_types"> <item>9</item> <!-- TYPE_MOBILE_ETHERNET --> </integer-array> <!-- The default iface on which to monitor data use --> <string name="config_datause_iface">eth0</string> • Update Logtags samples in framework's services/java/com/android/server/EventLogTags.logtags: 51102 netstats_ethernet_sample (dev_rx_bytes|2|2),(dev_tx_bytes|2|2),(dev_rx_pkts|2|1),(dev_tx_pkts|2|1),(xt_rx_bytes|2|2), (xt_tx_bytes|2|2),(xt_rx_pkts|2|1),(xt_tx_pkts|2|1),(uid_rx_bytes|2|2),(uid_tx_bytes|2|2),(u id_rx_pkts|2|1),(uid_tx_pkts|2|1),(trusted_time|2|3),(dev_history_start|2|3) • In framework's ethernet/java/android/net/ethernet/EthernetStateTracker.java: - One need to add support for LinkProperties LinkProperties mLinkProperties = mDhcpInfo.makeLinkProperties(); mLinkProperties.setInterfaceName("eth0");
36. 36 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Network Statistics • In framework's services/java/com/android/server/net/NetworkStatsService.java: - Need to collect Ethernet samples. import static android.net.NetworkTemplate.buildTemplateEthernet; NetworkTemplate template = buildTemplateEthernet(); devTotal = getSummaryForNetworkDev(template, start, end).getTotal(devTotal); devHistoryStart = getHistoryStartLocked(template, mNetworkDevStats); xtTotal = getSummaryForNetworkXt(template, start, end).getTotal(xtTotal); uidTotal = getSummaryForAllUid(template, start, end, false).getTotal(uidTotal); EventLogTags.writeNetstatsEthernetSample( devTotal.rxBytes, devTotal.rxPackets, devTotal.txBytes, devTotal.txPackets, xtTotal.rxBytes, xtTotal.rxPackets, xtTotal.txBytes, xtTotal.txPackets, uidTotal.rxBytes, uidTotal.rxPackets, uidTotal.txBytes, uidTotal.txPackets, trustedTime, devHistoryStart); • Adding ConnectivityManager.TYPE_ETHERNET support to Monkey's NetworkMonitor - Used to display time spent proceeding data from Ethernet interface.
37. 37 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Dive Into Android Networking: Adding Ethernet Connectivity Next Steps ? • Properly redesign the ECM patch to match WiFi architecture. • Port from Ice Cream Sandwich to Jelly Bean - Check if original ECM patch has been updated since early 2012. - Current changeset with extra features is 504 kB big. • Design Ethernet HAL for 802.1x / WPA support. • Contribute / upstream to Linaro ? • And then to Google ?
38. 38 COPYRIGHT © 2012 ALCATEL-LUCENT. ALL RIGHTS RESERVED. Thank You Dive Into Android Networking: Adding Ethernet Connectivity Thanks