Cisco Cisco AnyConnect Secure Mobility Client v3.x Release Notes

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Release Notes for Cisco AnyConnect Secure Mobility Client 3.0.x for Android Mobile Devices
 
  Known Issues and Limitations
We are pleased to report that Android 4.4 (KitKat) bug Google Issue #61948 (AnyConnect users will 
experience High Packet Loss over their VPN connection /users will experience timeouts) has been 
resolved in Google's release of Android 4.4.1 which Google has begun distributing to some devices 
via Software Update. The following problem information is provided for reference: 
Due to a bug in Android 4.4 (
also see the
), AnyConnect 
users will experience High Packet Loss over their VPN connection. This has been seen on the 
Google Nexus 5 running Android 4.4 with AnyConnect ICS+. Users will experience timeouts 
when attempting to access certain network resources. Also, in the ASA logs, a syslog message 
will appear with text similar to "Transmitting large packet 1420 (threshold 1405)." 
Until Google produces a fix for Android 4.4, VPN administrators may temporarily reduce the 
maximum segment size for TCP connections on the ASA by configuring the following sysopt 
connection tcpmss <mss size>
. The default for this parameter is 1380 bytes, reduce this value 
by the difference between the values seen in the ASA logs. In the above example, the difference 
is 15 bytes; the value should thus be no more than 1365. Reducing this value will negatively 
impact performance for connected VPN users where large packets are transmitted.
AnyConnect for Android may have connectivity issues when connecting to a mobile network using 
the IPv6 transition mechanism known as 464xlat. Known affected devices include the Samsung 
Galaxy Note III LTE connecting to the T-Mobile US network. This device defaults to an IPv6 only 
mobile network connection. Attempting a connection may result in a loss of mobile connectivity 
until the device is rebooted. 
To prevent this problem, use the AnyConnect ICS+ app, and change your device settings to obtain 
IPv4 network connectivity or connect using a Wi-Fi network.
For the Samsung Galaxy Note III LTE connecting to the T-Mobile US network, follow the 
 to set the Access Point Name (APN) on your device, making 
sure APN Protocol is set to IPv4
The AnyConnect ICS+ package may have issues when a private IP address range within the VPN 
overlaps with the range of the outside interface of the client device. When this route overlap occurs, 
the user may be able to successfully connect to the VPN but then be unable to actually access 
anything. This issue has been seen on cellular networks which use NAT (Network Address 
Translation) and assign addresses within the 10.0.0.0 - 10.255.255.255 range, and is due to 
AnyConnect having limited control of routes in the Android VPN framework. The vendor specific 
Android packages have full routing control and may work better in such a scenario.
An Asus tablet running Android 4.0 (ICS) may be missing the tun driver. This causes AVF 
AnyConnect to fail.
On a rooted device, in the superuser application preferences, Automatic response must be set to 
Prompt. Other settings may cause AnyConnect to hang. 
Due to Android issue 
, when pasting text from the clipboard, a space is inserted in front of the 
text. In AnyConnect, when copying text such as a one time password, the user has to delete this 
erroneous white space.
Guidelines and Limitations
Cisco IOS routers do not support the Cisco AnyConnect Secure Mobility client for Android at this 
time.
AnyConnect for Android supports only the features that are strictly related to remote access.
The ASA does not provide distributions and updates for AnyConnect for Android. They are 
available only on Google Play.