ACCESS NETWORK--WIRELINE

 

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Let us start with wired access network.

 

Network diagram of 1st generation ( POTS—plain old telephone system )( fig-1 )::

 

Text Box: SUBSCRIBER X Text Box: SSS  

Text Box: COPPER ACCESS NETWORK IN LOCATION X OF CITY  

 

 

 

 

 

 

Text Box: BUILDING A Text Box: SUBSCRIBER Y  Building A is telephone exchange, there used to be mechanical exchanges with operator.

 

Subscriber X wants to talk to subscriber Y….X will dial operator code and will request to connect to subscriber Y ( mechanical switching by operator )

 

When number of connections increased and it was need of hour for automation than come auto electro-mechanical exchanges known as STROWGER  EXCHANGES

 

In automatic switching , subscriber X dials number assigned to subscriber Y and gets connected without any human interference

 

Old exchanges were electro-mechanical in nature i.e calls used to be routed with functioning of relays ( same as that of gear function in automobiles )

 

New generation systems have electronic switching which is based on LOGIC functioning of electronic circuits  with additional features embedded i.e IVR ( interactive voice ) , dial back tones , busy tones , toll free numbers , CLI ( caller line identification ) , voice mail box etc.

 

Access network need to be connected to central switch so that different subscribers can dial number

 for connectivity.

Text Box: SUBSCRIBER B

                                                        

Text Box: SUBSCRIBER D

 

 

Text Box: SUBSCRIBER C

 

 

 

 

 

Text Box: CENTRAL SWITCH

Text Box: COPPER ACCESS NETWORK IN LOCATION Y OF CITY  

 

 

Text Box: SUBSCRIBER A  

 

 

 

 

 

 

 

Old systems used to have copper in last mile ( incumbent network ).

 

 

Copper cables are  laid underground from exchange to subscriber premises with detailed planning of MDF ( main distribution frame ) ,  pillar boxes ,Street boxes and DP ( distribution box )

 

Copper cables roll-out take place with following specifications ::

 

a)     26 AWG ( 0.40 mm copper dia cables )( american wire gauge )

b)     24 AWG ( 0.51 mm copper dia cables )

c)      22 AWG ( 0.63 mm copper dia cables )

 

Typical distance between individual subscriber and  exchange used to be 5.0 kms ( 3 miles )….this parameter is dependent on LOOP RESISTANCE.

 

Apart from this ,exchange feeds -48 VDC supply to telephone sets

 

 

For detailed information , please contact :: vsaxena69@hotmail.com