Updated: Sep 15
What is Networking?
Networking is a core of Information Technology (IT), and is one the fastest growing areas of IT. It involves the process of building, using, and maintaining computer networks – including hardware, software, and protocols.
What is Networking Model
A network model reflects a design or architecture to accomplish communication between different systems. Network models are also referred to as network as protocol suits. It mainly categorises three parts
OSI (Open System Interconnection by ISO “International Organisation for Standardisation)
TCP/IP (Transport Control Protocol/ Internet Protocol
Devices and Protocol Referencing
Layer 2 Switching VLAN
A layer 2 switch can assign VLANs to specific switch ports, which in turn are in different layer 3 subnets, and therefore in different broadcast domains. VLANs allow for greater flexibility by allowing different layer 3 networks to be sharing the same layer 2 infrastructure.
A VLAN (Virtual Local Area Network) is a logical collection of devices such as workstations, servers and network devices that are connected in the manner such that they appear to be on the same LAN despite their geographical distribution. LANs are implemented to achieve security, scalability and quick to adapt changes in network requirements and relocation of workstations and server nodes.
There are many Reasons why we need VLANs
When you have two departments both are connected two one switch. It means one department belongs to one network or one broadcast domain. One domain means when one computer broadcast everyone can respond. This type of network design could response problems, at least one traffic congestion and poor performance. If there are too many users in one broadcast.
Different Departments share their confidential documents in same network. And it occurs third party can access to the confidential data and data can be harm.
After I understand these two problems there are some options can use for them:
We can use more switches and routers Sales department can use their own switch and another Finance department can use their own switch. Now there are in two independent networks and two separate broadcast domains with a layer 3 devices or Router in between two networks can talk to each other without any interruption.
We can create one VLAN with one switch. Physically those two departments share on physical switch but virtually they are in two different independent VLANs .In addition can use one router so that two VLANs can talk to each other using trunk. Trunk can carry different network data over one physical line simultaneously.
We can use Multilayer switch to create two independent VLANs. So the difference is that we don’t need physical router in between instead, these two VLANs can share and talk to each other using Inter VLAN Routing technique. Multilayer switch we can create different VLANs and provide routing abilities across the VLAN without physical router in between.
Benefits for Choosing Smaller Broadcast domain
To reduce received broadcast frames on each device
Reduce security risks, reducing the number of hosts that receive copies of frames that switch flood
Improve security for hosts with sensitive data
Flexible designs that group users by department instead of by physical location