The Delhi Zone of Indian Army has set up a SynchronousDigital Hierarchy (SDH) network based on STM-1 called Delhi Zone Access Network(DZAN) designed to meet the growing bandwidth needs of Indian Army organizationsin Delhi. It helps in convergence of all types of communications includingvoice, data, image, and video–conferencing. The network can be integrated withthe Army satellite network making communication easy within DZAN network. Itwill also help in connecting to other Army commands in the central, east, west,and south along with the Army headquarter, once the VSAT link is established.

The earlier network, based on the MTNL backbone, was badlynetworked and access within different offices in the Delhi region was a problem.Being a public network, security was also a problem. The use of optical fibre inthe backbone and copper in the local loop has solved the security as well asaccess problem, says Brig RK Malik, commandant, Army Headquarters Signals.

In the first phase of the network around 700 subscribers havebeen connected to six different nodes located in Dhaula Kuan, SP Marg, ArjunVihar, Mahipalpur, Shankar Vihar, and EDP Enclave. Around 12 km of optical fibrehas been laid in the mountainous terrains of Delhi. Around 19 km is still to belaid out. In the second phase seven additional optical nodes are to beestablished at Sena Bhawan, RK Puram, Ridge Road, Delhi HQ area, R&RHospital, South Block, and Army House. In the third phase four more opticalnodes are to be established and DZAN infrastructure will be utilized totransport 64 Kbps data and voice channels over entire Delhi from the ArmyIntranet.

The total cost of the project is Rs 9 crore of which Rs 2.5crore has been utilized in the first phase.

The system is based on STM-1 and provides bandwidth up to 155Mbps that can be upgraded to STM-4 providing bandwidth of 622 Mbps. In thebuilding premises copper is used providing a bandwidth of 64 Kbps. Initially,the network will be used for voice and data connectivity. In future, the networkwill be also used for videoconferencing and Virtual Private Network solutionsfor closed user groups.

The DZAN network is based on Bandwidth Manager 3600 ofNewbridge and ISDN switch from Alcatel called Omni PCS 4400. One can increasethe bandwidth using voice compression and ADPCM technology. Even the NetworkManagement System is flexible as it can be monitored from any node. One can alsotrack the fault down to a card level thereby decreasing the downtime.

This network is an important milestone for the northerncommand of Indian Army. In future more secure networks coming up that willstrengthen the intelligence wing of Indian Army.

Pravin Prashant