If you are studying for a CCNA, you will find useful links and information here.
Here’s an outline of the CCNA syllabus: (Note: This is a very brief outline. For the official syllabus click here: https://learningnetwork.cisco.com/community/certifications/ccna/syllabus)
- OSI stack
- TCP/IP v4 in depth.
- TCP/IP v6 overview
- Basics of Cisco IOS, including how and where the configuration is stored, backup and restore, setting up passwords, telnet, etc.
- Layer 2 switching. VLANs, including VTP, dot1q, and inter VLAN switching.
- Spanning Tree Protocol
- Static routing.
- Dynamic routing: RIP version 1 and 2 and the differences between them.
- Dynamic routing: EIGRP – configuring, commands and load balancing.
- Dynamic routing: OSPF
- Cisco SDM (overview)
- LAN technologies: DHCP, DNS, NAT, ACLs
- WAN interfaces
- PPP
- Frame Relay
First tip: GNS3 software to make up a virtual router lab.
Second tip: Free short course and exam: Charles Sturt University. A good start. http://www.itmasters.edu.au/free-short-course-cisco-ccna/