Landline Telephone Exchanges, Capacities, Connections, Internet bandwidth, ADSL, GPON, Domain, Call Traffic
Time Telephone (PSTN) Bandwidth (Data-Internet) Bcube (ADSL internet) Triple Play (GPON voice/internet/Video-TV) Domain (.bd) Telephone Traffic (international)
30-Jun Number of Exchanges Telephone Capacity Telephone Connection Satellite Bandwidth Submarine Cable Bandwidth                   incoming outgoing
of the year- (down + up speed) Capacity Connection Comment Coverage Capacity Connection Comment Coverage   (million minutes)
Bangladesh Telegraph and Telephone Board (BTTB) Bangladesh Telegraph and Telephone Board (BTTB)    
1985 561 171834 151411                          
1986 580 187731 163959                          
1987                                
1988   203706 183115                          
1989   224660 192990                          
1990   244748 205500                          
1991   248505 216327                          
1992   253863 232730  
BTCL_logo.gif
                     
1993 620 269492 245947                        
1994 617 295982 262274                        
1995 621 314980 286605                        
1996 629 387769 316081                          
1997 621 440491 368017                          
1998 628 462573 412747                          
1999 631 474322 432968                          
2000 653 579794 491303                          
2001 662 688920 564880 2.5 Mbps                        
2002 668 746078 605931 2.5 Mbps                        
2003 652 920993 716721 6+4 Mbps                        
2004 638 966349 810158 14+8 Mbps                        
2005 698 1010009 857358 16+8 Mbps                        
2006 731 1203057 889174 24+8 Mbps 2xSTM1                      
2007 711 1328813 877522 24+8 Mbps 8xSTM1                      
Bangladesh Telecommunications Company Limited (BTCL) Bangladesh Telecommunications Company Limited (BTCL)    
2008 697 1315813 836111 24+8 Mbps 3xSTM4+8xSTM1                      
2009 693 1315030 866784 48+24 Mbps 4xSTM4+8xSTM1 19425 100               4310 351
2010 693 1326159 971746 48+24 Mbps 6xSTM4+4xSTM1  44500 5000   26 Zilla           3143 253
2011 698 1365386 990494 48+24 Mbps 9xSTM4 46848 8273   35 Zilla           4655 174
2012 MSU 263+RSU 484=747 1428381 935760     46878 12000                  
Exchanges in 626 locations                      
2013 MSU 216+ RSU/ONU 513=729, Exchanges in 580 locations 11471983 903299 28+8 Mbps (Internet), 36.5 Mbps Duplex (Voice) 3xSTM16+1xSTM4= 8 Gbps (Data), 32xSTM1= 5 Gbps 47000 13000   45 Zilla 0 0     11533 2390 66
                           
2014 MSU 243+ RSU/ONU 475=718, Exchanges in 595 locations 1471635 846174     89000 15440 DSLAM: 47K + ONU:42K=89K 45 Zilla 7848 0 1.71 lac (RODTS) project generates GPON/Softswitch services. 1/2/4 Mbps at Mirpur DOHS. 20Mbps per user designed, but board approved upto 4Mbps for internet. HD-IPTV will consume 8-12Mbps.        
                                                                                      (source: Printed Annual Reports of BTTB/BTCL)
 
What is E1?
 
A communication line that was developed by European standards that multiplexes thirty
voice channels and two control channels onto a single communication line. The E1 line
uses 256 bit frames and transmitted at 2.048 Mbps.
 
                                                                                             (courtesy: http://www.telecomdictionary.com/)
 
What is STM?
 
SDH Rates: SDH (Synchronous Digital Hierarchy) is a transport hierarchy based on
multiples of 155.52 Mbit/s. The basic unit of SDH is STM-1. STM-1 means Synchronous
Transport Module. Level-1.
 
Different SDH rates are given below:
 
STM-1 = 155.520 Mbit/s
STM-4 = 4xSTM-1 = 622.080 Mbit/s
STM-16 = 16xSTM-1 = 2,488.320 Mbit/s (~2.5 Gbps)
STM-64 = 64xSTM-1 = 9,953.280 Mbit/s (~10 Gbps)
 
Each rate is an exact multiple of the lower rate, therefore the hierarchy is synchronous.
 
 
What are SONET, SDH, PDH?
 
Synchronous optical networking (SONET) and synchronous digital hierarchy (SDH) are
standardized multiplexing protocols that transfer multiple digital bit streams over optical
fiber using lasers or light-emitting diodes (LEDs). Lower data rates can also be transferred
via an electrical interface. The method was developed to replace the Plesiochronous
Digital Hierarchy (PDH) system for transporting larger amounts of telephone calls and data
traffic over the same fiber without synchronization problems.
 
                                                                                                            (courtesy: http://www.wikipedia.org/)