[ibr-dtn] Install ibr-dtn on TP-LINK 3040

Hi all, I have recently started working on DTN and I tried to install ibr-dtn on TP-LINK routers (TL-MR3040) ver.1.0. After installing OpenWRT on them, I followed the procedure for downloading IBR-DTN for OpenWRT from your website. Nevertheless, while trying to install ibrdtn package, I received the following error.

root@OpenWrt:/etc# opkg install ibrdtnd Installing ibrdtnd (0.10.2) to root... Collected errors: * verify_pkg_installable: Only have 244kb available on filesystem /overlay, pkg ibrdtnd needs 479 * opkg_install_cmd: Cannot install package ibrdtnd.

How can I overcome this issue? I have plugged a USB adapter, but I was not able to configure it properly to install there the packages. Thanks in advance!

Best, Theodoros