TY  - BOOK
AU  - Zacker, Craig 
TI  - Upgrading & troubleshooting networks: : The complete reference 
SN  - 0-07-041267-7
PY  - 2008///
CY  - New Delhi: 
PB  - Tata Mcgraw-Hill Publishing Company Limited, 
KW  - Networks
KW  - OSI reference model
ER  -