These pdfs contains the lecture notes that I have prepared during teaching of Computer Network at Nepal Engineering College. These pdf are mostly prepared from course Text books
1. Data Communication and Networking. Forouzan
2. Data and Computer Communication. William Stallings.
3. Computer.Networks Tanenbaum
4. IIT Video lectures
5.Computer-Networking-A-Top-Down-Approach-Featuring-The-Internet Kurose-and-Ross
and CCNA online Curriculum prepared by Cisco Inc , Wikipedia and others.
Emergence of Network , principle of communication Network ,Reference Model and Multiplexing
Network Topology and Architecture
OSI Reference Model
TCP/IP Reference Model, IP Addressing and Subnetting
Network and Internet Layer
Data Link layer
Physical layers and its Design issues
Network Severs and Protocols
Network Management and Security
Introduction to Socket Programming
This chapter 10 pdf also contains the topics ipv6 and DES that was left during the lecture hour.
All lecture notes in a single PDF
daya's blog 
thank u sir…thank u very much
A marvellous job made simole for us teachers. Thank you very much Sir.