1) OSI model inside and out. Know what each layer does with the information passed from both above and below it. Know which applications use which layer, i.e, MPEG, JPEG, RPC, SQL, EBCDIC, ASCII, Encryption.

2) Frame Relay as applicable to WAN protocols. I had so many questions on Frame Relay it was unbelievable (10-15).

3) Had several questions on ISDN. Know the difference between TE1, TE2, NT-1, and U. Know the difference between BRI and PRI. There weren't that many questions, they were evenly divided between "gimmes" and impossible, but if you can study for the impossibles, they are some free points.

4) Know access lists. Know the implicit deny all, know how a deny filter that doesn't specifically state inbound or outbound will filter. Know wildcard masks (not just the 0 and 255 ones either).



OSI MODEL

Layer 7 - Application:

The Application layer provides services to the software through which the user requests network services. This layer is not nor does it contain any applications, and your computer application software is not on this layer. In other words, a program like Microsoft Word does not exist at this layer, but browsers, FTP clients and mail clients do.

Layer 6 - Presentation:

This layer is concerned with data representation and code formatting.

Layer 5 - Session:

The Session layer establishes, maintains, and manages the communication session between computers.

Layer 4 - Transport:

The functions defined in this layer provide for the reliable tranmission of data segments as well as the disassembly and assembly of the data before and after transmission.

Layer 3 - Network:

This is the layer on which routing takes place. The Network layer defines the processes used to route data across the network and the structure and use of logical addressing.

Layer 2 - Data Link:

As its name suggests, this layer is concerned with the linkages and mechanisms used to move data about the network, including the topology, such as Ethernet or Token Ring, and also deals with the ways in which data is reliably transmitted.

Layer 1 - Physical:

The Physical layer's name says it all. This layer defines the electrical and physical specifications for the networking media that carry the data bits across a network.


Routers

Network Segmentation

Router Basics

Routed vs. Routing Protocols

Network Addressing

Subnetting

TCP/IP



Books I am using to study for the exam.

cover - This is a good basic book. I first bought the Todd Lammle book and found myself having to re-read pages. I then got the dummies book and now am crusing through the Lammle book with ease.
cover - This book by Todd Lammle is considered "the book" for the CCNA exam. I have spoken with may people who only read this book and passed the test. Very in depth and well organized.

Links to other study notes

CCNA Study Sanctuary

CCNA Study Notes





Jokes - Comics