Why Would a Layer 2 Switch Need an IP Address (Know the Fact)

A layer 2 switch is a network switch that operates at the OSI model’s data link layer (layer 2). As such, it is in charge of transmitting packets between devices on the same network segment. To accomplish this, the switch must have an IP address in order to send and receive packets.

Layer 2 switches are part of the switch family and can only connect via MAC addresses. This makes them fast and efficient, but limits network capacity and connectivity. 

Moreover, layer 2 switches use IP addresses for internal and external communication between devices on the same network or on separate subnets with overlapping IP ranges. The following are some reasons layer 2 switches need IP addresses.

What Are the Function of Layer 2 Switch

Layer 2 switches, also known as data link layers, connect each computer on the network. A layer two switch, unlike a router, can broadcast messages to all ports at once. You can use the layer two switch’s single IP address for the full LAN instead of allocating addresses to each computer individually.

What Are the Usages of Layer 2 Switches

LANs employ Layer 2 switches to segment network traffic. This allows bandwidth to be allocated where it is needed while also preventing network congestion. They serve as the backbone of wired networks and are frequently the first devices to be placed when a wired network is set up. 

A layer two switch does not provide routing or bridging and instead operates at the OSI model’s data link layer.

Reasons Why a Layer 2 Switch Needs an IP Address

Here are some of the reasons why a Layer 2 switch requires an IP address.

1. Each Switch Has a Distinct Ip Address

A layer two switch, like any other network device, requires its own distinct address. The most popular type of addressing for network devices is an IP address. It enables computers to recognize one another as well as the location and type of network to which they are linked. 

Layer two switches are network switches that have their own IP addresses and perform packet filtering and routing at this level in the OSI model.

2. To Improve Network Management

The IP address is used by a layer-2 switch to connect with other network devices. To be able to do so, it must be set up with this information. In addition, it will often run a DHCP server, which assigns IP addresses dynamically as clients or other devices request them.

3. Designate VLANs

A layer 2 switch would require an IP address for a variety of reasons. The ability to remotely configure the device is the most obvious. Another reason is that you may have devices on different networks that need to connect with each other, requiring you to assign them both to the same VLAN on the switch. 

Finally, if you wanted to manage your layer 2 switches using SNMP, you’d need to give them an IP address.

4. Designate VLANs to Connect the Switches to the Rest of the Devices

It’s simple to connect switches to other devices. If the switch is connecting to another network device, such as a printer or computer, it will need an IP address. If the switch is linked to more than one network, a router may also be necessary.

5. For Inter-Switch Control Packet Exchanges

In order to connect with other layers 2 switches, a layer 2 switch will often have an IP address. This is due to the fact that the switches must exchange control packets in order to interact, and there is no native mechanism for them to do so without exchanging IP addresses. The IP address is typically assigned statically rather than dynamically.

6. LACP Trunking and 802.1Q Tunneling Need Ip Addresses

IP addresses are not assigned to Layer 2 switches, but they are required for 802.1Q tunneling and LACP trunking. This is due to the fact that when frames are transmitted from one device to another, they must include the destination’s MAC address.

Moreover, they also need the source’s MAC address in order to be delivered correctly. Based on the destination MAC addresses in the frame, the layer 2 switch must know which ports to forward frames out of.

7. Use ACLs to Protect Access

ACLs (Access Control Lists) are used to secure switches. You can use access control lists to designate which devices can connect to your switch and what kind of traffic they can send. ACLs are critical for protecting your network from intruders.

What Are the Advantages of Getting IP Adress

• An IP address is required for packets to be routed from one network to another.
• To obtain an IP address, the switch must first register with the DHCP server.
• If the switch is to be used as a default gateway, it will require an IP address.
• Remote access, such as SSH or telnet, requires the switch to have its own IP address.
• Without an IP address, the switch is unable to communicate with other network devices.
• A layer 2 switch must be set as part of your router’s LAN interface so that traffic may be routed through it and out into the Internet.

What Are the Disadvantages of Getting IP Adress

• A layer 2 switch cannot route packets across networks.
• A layer 2 switch cannot connect two distinct networks together, such as joining a network’s LAN and WAN.
• If the network has several VLANs and more than one IP scheme, allocating addresses for each VLAN will be difficult.
• Subnetting may allow it to handle several VLANs with a single IP address, but it complicates troubleshooting.

Last Words

Many networks rely on Layer 2 switches. They are frequently used to enable network segmentation or the division of computer networks into distinct and secure subsections. 

Network managers can construct virtual LANs, or VLANs, by isolating one set of computers from another using Layer 2 switches. IP addresses are generally required on layer two switches for these and other reasons.