Hey as per my idea there are various branches of Tata communications ltd in Delhi and here I am giving you its details

Tata Communications Limited
Tata Communications Limited is a global Telecom Indian business conglomerate Tata Group. The company’s infrastructure includes sub-sea, terrestrial communications networks, data centers and it provides fixed line and wireless services. It also holds shares in Neotel in South Africa

Subsidiaries
Tata Communications Transformation Services (TCTS)
Tata Communications Data Centers Limited (TCDC)
Tata Communications Payment Solutions Limited (TCPSL)

Tata communications ltd in Delhi

Tata Communications Ltd
Internet Service Provider
21, Greater Kailash I
092686 88355

Tata Communications Ltd
Internet Service Provider
Tata Communications Ltd, 2 Bangla Sahib Road CP,
092123 88553

Tata Communications
Telecommunications Service Provider
Old Wireless Building, Opposite Savitri Cinema, Greater Kailash 1
097119 11150

Tata Communication Shop
Telecommunications Service Provider
Mandir Wali Gali, Palam, Mahavir Enclave Part 1