1. Network Fundamentals

1. OSI and DoD Models

1.2 DOD Model and it’s capacity

DOD Model maps to OSI demonstrate as beneath:

IP is the convention that works at the Internet layer. It advances the parcels dependent on the system address (IP address) in the bundles and the steering tables.

The four layers of DoD demonstrate from Top to Bottom are:


1. Process Layer: Responsible for the usage of client level applications, for example, mail conveyance, document exchange, and remote login.

2. Host-to-Host Layer: Responsible for stream control, and retransmission of lost parcels. TCP and UDP conventions work at this layer.

3. Web Layer: Responsible for steering information over a system of systems. Steered conventions, for example, IP work at this layer. Steering conventions are likewise connected with this layer.

4. System Access Layer: Responsible for the conveyance of information fragments over a given specific equipment media. Distinctive conventions, for example, CSMA/CD work at this layer.

More Information :

Repeaters work at Physical (Layer 1),

Straightforward Switches work at layer 2 of OSI demonstrate, or, in other words, Layer. A switch takes a gander at the goal MAC address before sending the casing.

Switches work at Network (Layer 3) of OSI Reference Model.

The application layer is in charge of guaranteeing the accessibility of planned correspondence accomplice. This layer is additionally in charge of synchronizing sending and getting applications.

Introduction Layer is in charge of arranging information exchange punctuation.

The session layer is in charge of coordinating correspondence between frameworks

The transport layer is in charge of multiplexing upper-layer applications. It is additionally in charge of the foundation and tears down of virtual circuits.

ARP (Address Resolution Protocol): IP works at system layer. The IP address is a sensible location. In the event that a bundle is to be conveyed to a goal machine, its physical location (MAC address) should be known. ARP is a convention, which empowers a machine to acquire its MAC address from a known IP address.

RARP (Reverse Address Resolution Protocol): RARP is utilized to acquire an IP address from a known MAC address.

BooTP (Bootstrap Protocol): When a diskless workstation is fueled on, it communicates a BootP ask for on the system. A BooTP server reacts with its IP address, Default entryway, and so forth.