sla based maintenance of ofc routes under hazaribagh ofc divison sla based maintenance of ofc routes , preventive , corrective and scheduled works for a period of one year for a total length of 265 km . , sla based outsourcing , ofc based route maintenance work ( sla ) including round the clock route-patrolling , jointing of interrupted cable , if required inserting additional cable between two ends ( preferably by doing underground and in extreme case by overhead ) . end to end optical power budget has to be kept within limit , for the same , if required , damaged / lossy section of ofc has to be replaced by new cable . all material ( except bsnl supply ) and labour should be supplied by the contractor including operating tools / instruments ( such as splicing machine ) and measuring meters ( such as otdr , power-meters ) etc . transportation of these materials and lying of ofc is the responsibility of the contractor . furnishing of detail reports of route and splice loss measurement with otdr may be submitted .