Maju reminded me about the language of IVC people by commenting on one of my previous posts on the same topic. Last time I wrote IVC spoke an extinct Caucasian language. The Caucasian language family is now mostly restricted to Caucasus mountains.
Before E3b clan from Africa, R1a1 clan from Central Asia, spread Afro-Asiatic and IE languages respectively to West Asia, most of the West Asia and Caucasus mountains were inhabited by Caucasian language speaking J1 hunter gatherer tribes. Please check Y-Haplogroup-J1 distribution among isolated endogamous communties that speak Caucasian languages in the region of Caucasus at Quetzalcoatl Anthropology forum.
It is possible that IVC might have spoken a language belonging to the same family. I suppose I claimed that based on the distribution of Ilishu-esque names via Google search. Iu Ilizhu was a translator from Meluhha recorded in Sumerian documents.
According to Maju, ili, iri etc.. are ancient West Asian terms of town or city. I suppose Dravidian Ur is very close. Incidentally, there are many place names in my region ending in "-ila" whose meaning is unclear at present.