TY  - BOOK
AU  - Sheldon, Tom 
TI  - Encyclopidia of networking and telecommunications 
SN  - 0-07-044742-X 
U1  - 004.603 SHE  
PY  - 2004///
CY  - Tata mcgraw hill 
PB  - New Delhi 
KW  - TELECOMMUNICATION
ER  -