Airtel 4G dongle works in Ubuntu 16.04.2 LTS

Step 1: sudo gedit /etc/usb_modeswitch.conf
DefaultVendor=0x19d2
DefaultProduct=0x1238

TargetVendor=0x19d2
TargetProduct=0x0017

StandardEject=1
MessageEndpoint=0x01
MessageContent="5553424312345678000000000000061b000000020000000000000000000000"
#MessageContent="55534243123456782000000080000c85010101180101010101000000000000"
#MessageContent="5553424312345678000000000000061b000000030000000000000000000000"
NeedResponse=1

Step 2: sudo usb_modeswitch -c /etc/usb_modeswitch.conf
Step 3: sudo apt-get install wvdial

Step 4: sudo gedit /etc/wvdial.conf
[Dialer Defaults]
Init1 = ATZ
Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
Init3 = AT+CGDCONT=1,"IP","airtelgprs.com"
Password = pass
Ask Password = 0
New PPPD = yes
Phone = *99#
Idle Seconds = 0
Modem Type = Analog Modem
Stupid Mode = 1
Compuserve = 0
Baud = 9600
Auto DNS = 0
Dial Command = ATDT
Modem = /dev/ttyUSB1
ISDN = 0
Username = user

Step 5: sudo wvdialconf
Step 6: sudo gedit /etc/ppp/options
Step 7: #'chat -v -f /etc/ppp/chat-ztisp'
Step 8: /dev/modemttyUSB2
115200

Step 9: sudo wvdial

Courtesy: http://blog.eternalthinker.co/2015/02/connect-airtel-4g-dongle-in-ubuntu-14-64-bit-network-manager.html