Updating BS - EPC routing

In NITOS, the BS is attached through a networking switch to the EPC network. The networking switch that is being used, is the experimental networking switch where all the second Ethernet interfaces of the nodes connect to (aka. eth1). You can easily update the configuration to the EPC and the BS in NITOS, in order to use another node as their gateway to the EPC (or even as the EPC and do some rewritting functions there).

Initially, you have to find out which eNB you will be altering. This is shown in the beginning of "Simple LTE Tutorial". In general, for the NITOS indoor testbed it is node=2.

In order to update the addresses at which the eNB is searching for the EPC network, you have to send the following commands:

wget -qO- "http://lterf:5054/lterf/bs/set?epcIpAddress=NEW_EPCIP_ADDRESS&&node=2" 
wget -qO- "http://lterf:5054/lterf/bs/set?pgwIpAddress=NEW_EPCIP_ADDRESS&&node=2"

The NEW_EPCIP_ADDRESS should be a string in plain text, containing the IP address (eg. 192.168.200.200).

You will need to update the femtocell configuration in the EPC network as well. You can retrieve the existing eNBs configured at the EPC network with the following command:

wget -qO- "http://lterf:5054/lterf/epc/get?function=getENodeBList" | xml_pp

The XML doc that is returned is containing information about the IDs of the eNBs which are configured at the EPC side. You can get more information about each one of the eNBs with the following command:

wget -qO- "http://lterf:5054/lterf/epc/get?function=getENodeB&args=eNB_IDENTIFIER" | xml_pp

where the eNB_IDENTIFIER is one of the IDs that are listed through the getENodeBList function.

You can further update this configuration by using the following command:

wget -qO- "http://lterf:5054/lterf/epc/get?function=updateENodeB&args=eNB_IDENTIFIER,NEW_IP_ADDRESS" | xml_pp

Or you can further add/delete eNBs with the following functions:

wget -qO- "http://lterf:5054/lterf/epc/get?function=addENodeB&args=eNB_IDENTIFIER,NEW_IP_ADDRESS" | xml_pp
wget -qO- "http://lterf:5054/lterf/epc/get?function=deleteENodeB&args=eNB_IDENTIFIER" | xml_pp

In order for these changes to take effect, restarting the Base Station and the EPC network is required.