nETWORK INTERFACE
Layer 1
In this course, we will concentrate on routing (Layer 3) and switching (Layer 2), which will be the main focus of our sessions together. Of course, we will also cover topics such as transport (Layer 4) and physical (Layer 1). Ultimately, by the end of this course, you will have the skills to route and switch, particularly with Nokia devices.
Layer 2
Data Link
At this layer, interesting network structures such as Virtual Local Area Networks (VLAN), Virtual Private LAN Service (VPLS), Epipe, and cPipe exist. Several protocols have been developed to facilitate networking at this level. Devices primarily communicate with each other on this layer using MAC addresses. Some of the protocols found on Layer 2 include ARP, ATM, Ethernet, Frame Relay, and FDDI.
The complexities in these protocols can be simplified into two key functions: 1) Frames are transmitted across the network. 2) Frames are directed to the correct destination by identifying the MAC addresses of the intended devices.
Layer 2 networks are classified into 3 categories.
1) Point to Point Network
2) Shared Networks
3)Circuit based Networks.
Layer 2 networks
Point to Point
This describes a direct connection between two devices, which can be established through a wired, cabled, or wireless link. It is straightforward and does not necessitate addressing the source or destination. Examples of this architecture that we encounter include:
1) The link between a device and its remote control
2) Microwave communication links
3) Connecting two computers with cables, among others.
an example of a protocol used here is the PPP - Point to point protocol
Shared Networks
A shared network, also referred to as a multipoint connection, occurs when multiple devices communicate with each other using the same medium, such as a cable, switch, or 802.11 protocol. Instead of a dedicated link, each device takes turns using the shared medium, with the sequence determined by whichever protocol the network engineer has chosen to implement, such as Ethernet.
an Example of protocol used here is the ATM
Circuit based Network
Circuit-based communication employs dedicated channels or virtual circuits to establish a connection between two devices in different locations. Sometimes, the system is designed so that the circuit is established only for the duration of transmission and is dismantled when not in use.
An example of the protocol used here is the Ethernet