TY  - BOOK
AU  - Halsall, Fred 
TI  - Data communications computer networks and open systems 
SN  - 81-7808-098-2 
U1  - 005.71 HAL  
PY  - 2003///
CY  - Pearson education asia 
PB  - New Delhi 
KW  - DATA COMMUNICATION
ER  -