What is the fine-grained topic of the following text: Aircel is racing to work out intra-circle roaming pacts with other telcos to keep its network running to allow its users to port out to other operators if they wish to, after tower operator GTL Infrastructure disconnected about a third of the struggling carrier’s telecom sites in several circles. Only return the topic.
Aircel's plans for intra-circle roaming pacts following disconnection by GTL Infrastructure