Managed Leased Line Network (MLLN)

Leased Line services with flexible access bandwidth

The MLLN is a Managed Leased Line Network system which is proposed to provide Leased line connectivity. With the State-of-the-art technology equipment, MLLN is designed mainly for having effective control and monitor on the leased line so that the down time is very much minimised and the circuit efficiency is increased thus achieving more customer satisfaction. This mainly deals with data circuits ranging from 64 KBPs to 2048 KBPs.

In MLLN network conventional PCM primary MUX and subscriber Modems are replaced by versatile MUX and network terminating units respectively. MLLN mainly consists of Digital Cross Connect (DXC), versatile MUX (V MUX), Network Terminating Units (NTU) and Network Management System(NMS). DXC's and VMUX's are inter connected via optical fibre links with alternate routing facility in case of any route failure. VMUX is in turn connected to NTU's placed at customer premises through 2 wire copper pair. At the top of it NMS is suitably placed at the Central location for effective control & monitor. NTUs are fully managed from NMS. They are programmable for different data speeds ranging from 64 KBPs (n x64 KBPs: nx1 to 32) depending upon the customer demand, thus having bandwidth control without changing Modem at his premises. NTUs operate on 230 V AC.

Features of MLLN

  • Control, Manage the leased line network
  • Bandwidth management as per the customer demand
  • Pro-active maintenance, without waiting for customer to book a complaint.
  • Self Diagnostic/software loops to check E1 connectivity to DXC, VMUX/software loops for checking copper pair at NTU point for immediately identifying the faulty section for trouble shooting .
  • Alternate routing in case of any route failure.
  • Generation of the periodic performance reports for self-analysis/customer.

Advantages to Customers:

  • Bandwidth management as per customer requirement(64 Kbps and nx 64 Kbps up to to 2048 Kbps ).
  • Saving the cost of modems. NTU is provided by BSNL without any charges.
  • Proactive maintenance
  • Time dependent bandwidth

Time Dependent bandwidth:- MLLN system is capable of providing deferential time dependent bandwidth on request. Following parameters shall be considered which accepting the request.

Minimum Period: One Month and in multiples thereof.
Minimum time per day: Six hours.
Bandwidth management: Bandwidth up-gradation shall be allowed. The down-gradation is not permitted. For example, a 512 Kbps circuit may be allowed to become 1024 Kbps for a minimum 6 hours per day(other 18 hours it may remain as 512 Kbps), but a 512 Kbps circuit cannot be downgraded to 128 Kbps for any period in the day.


a) NTU :
  • Annual Rental - As applicable (see tariff for leased line less than 2 Mbps)
  • Security Deposit (Refundable) - Rs. 10,000/- per NTU.

b) Time Dependent Bandwidth :
  • Time dependent higher B/W charges per month: (Difference in charges of two bandwidths per month) x1.5 fixed) x hours per day (minimum 6 hours) /24.
  • Charges for period more than one month but less than one year : In multiples of one month.
  • Charges for one year or more (at one time) : (Monthly charges as per (i) above x number of months) less 15% as discount. The period beyond 1 year shall be in multiples of complete month only.

c) Leased Line Charges:
The normal leased line charges apply
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