Configuring Cisco ISR 1100 router for 4g/3g Cellular communication


For ISR1100 router introduction please visit my blog ISR1100 Introduction

Coming to 4g configuration, this is really interesting topic which I wanted to pick for a very long time and thankfully I got newly manufactured and fresh in market router in my hand. This is Cisco ISR1100 router which comes in many variant and is just like the old 800 series routers. Cisco has WLAN model, LTE model, DSL model and normal enterprise router model for this platform.The difference between old 800 routers and this platform is that this is IOS-XE based device with enhanced performance. You can find more details on Cisco website about the model. I will also try to put some introduction blogs for this.

Lets come to the point and configure Our Cisco ISR 1111-4PLTEA router for cellular communication. Before jumping into CLI we need to get a SIM card and an Antenna(no good signal in lab ūüôĀ ) . Router has slots available for two SIM cards on the device. I have inserted Airtel (4G subscriber in India) SIM card in the router . You can see below image with SIM card and the Antenna installed.


C1111-4PLTEA SIM and Antenna
C1111-4PLTEA SIM and Antenna


Once the above setup is done we need to enable cellular communication through the CLI configurations. Below is step by step configuration.

We need to configure profile with the APN name which is in our case. You can get this information from the provider.

C1111-4PL#cellular 0/2/0 lte profile create 1

Now once the cellular profile is activated we can start configuring the cellular interface and NAT etc so that we can have internal hosts in the network to communicate the outside world.

Gig0/0/0 is the interface which connects to my internal network and the cellular0/2/0 is the once bind with SIM slot 0.¬† Check out the configurations below …

interface GigabitEthernet0/0/0
 ip address
 ip nat inside
interface Cellular0/2/0
 ip address negotiated
 ip nat outside
 dialer in-band
 dialer idle-timeout 0
 dialer-group 1
 ipv6 enable
 pulse-time 1
ip nat inside source list 1 interface Cellular0/2/0 overload
ip route Cellular0/2/0
access-list 1 permit any
dialer-list 1 protocol ip permit

If you are familiar with the cellular configuration on the 800 series router you will notice that we do not need to specify the encapsulation(Slip,ppp,hdlc etc ) here.

One this configuration is done DO NOT forget to start the “interesting traffic” for the dialer ACL defined range. Else you would not see the cellular interface negotiating IP address.

C1111-4PL#sh interfaces cellular 0/2/0
Cellular0/2/0 is up, line protocol is up
 Internet address is
 MTU 1500 bytes, BW 50000 Kbit/sec, DLY 20000 usec,
 reliability 255/255, txload 1/255, rxload 1/255
 Encapsulation HDLC, loopback not set 
 Keepalive not supported
 DTR is pulsed for 1 seconds on reset
 Last input never, output 14:32:42, output hang never
 Last clearing of "show interface" counters never
 Input queue: 0/375/0/0 (size/max/drops/flushes); Total output drops: 0
 Queueing strategy: fifo
 Output queue: 0/40 (size/max)
 5 minute input rate 0 bits/sec, 0 packets/sec
 5 minute output rate 0 bits/sec, 0 packets/sec
 9235 packets input, 1563495 bytes, 0 no buffer
 Received 0 broadcasts (0 IP multicasts)
 0 runts, 0 giants, 0 throttles
 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
 14387 packets output, 896568 bytes, 0 underruns
 0 output errors, 0 collisions, 3 interface resets
 0 unknown protocol drops
 0 output buffer failures, 0 output buffers swapped out
 0 carrier transitions

C1111-4PL#show ip interface brief
Interface               IP-Address      OK?    Method    Status   Protocol
GigabitEthernet0/0/0      YES    NVRAM      up       up
Cellular0/2/0    YES    IPCP       up       up

Following are few verification commands, you can see I am able to reach to the outside world, ping for is working and the signal strength is also good after putting Antenna to the router. Before that the signal strength was less than -110 dBm and I was getting hardly any ping response.

4G LTE radio signal strength
Signal Strength and Ping

You can see the packet input and output stats for a particular profile with the help of cellular connection command.



There are many other verification commands but I think above set of details should be enough for you to verify a working Cellular connection.

Thanks and reaching out to this blog please rate the post and follow the blog for email updates about new posts.

Stay tuned and happy learning.


2 thoughts on “Configuring Cisco ISR 1100 router for 4g/3g Cellular communication

  1. CISCO 1921 ISR is not supporting the encapsulation type SLIP.
    It says “only ppp supported”
    I changed IOS as well, but of no use.
    Kindly if anyone can suggest the solution?????
    How can I enable SLIP on CELLULAR INTERFACE…

Leave a Reply