What makes a switch layer 3

Within a layer 2 switch environment exists a broadcast domain. Any broadcast traffic on a switch will be forwarded out all ports with the exception of the port the broadcast packet arrived on. Broadcasts are contained in the same layer 2 segment, as they do not traverse past a layer 3 boundary. Large layer 2 broadcast domains can be susceptible to certain unintended problems, such as broadcast storms, which have the ability to cause network outages.

Also, it may be preferable to separate certain clients into different broadcast domains for security and policy reasons. This is when it becomes useful to configure VLANs. 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. Researchers felt this was too complicated, so they came up with the idea of a layer 3 switches that acted as routers with fast forwarding done through the underlying hardware. This is why the main difference between layer 3 switches and routers lies in the hardware. Just like any product, a layer 3 switch also comes with its own share of downsides.

Cost is one of the major downsides to a layer 3 switch. It costs much more than a traditional switch and configuring and administering these switches also requires more effort. So, an organization should be ready to spend extra resources to set up layer 3 switches.

Layer 3 switches are most applicable only for large intranet environments with many device subnets and traffic. Homes and small organizations do not need these switches. Lack of WAN functionality is another major disadvantage with layer 3 switches. When compared to layer 2 switching, layer 3 routing is relatively slower.

This can be an issue when you want to span VLAN over multiple switches for supporting multiple tenants and virtualization. This limitation means you have to plan well to avoid one LAN from using multiple switches. Now comes the big question: Do you need a layer 3 switch at all for your network?

Well, it depends on your network configuration and its size. If you answered yes to one or more of the above questions, you sure need a layer 3 switch for improved performance. In all other cases, it is optional. Layer 3 switches act as both switches and routers. But within VLANs, it gives you multiple options to manage your bandwidth efficiently. This is why layer 3 switches are a powerful and scalable technology for building high-performance Ethernets.

Have you implemented a layer 3 switch in your organization? Can you please share your experience with our readers in the comments section? Home » Networking » What is a layer 3 switch and why would your network need it? Lavanya Rathnam is a professional writer of tech and financial blogs. Creative thinker, out of the boxer, content builder and tenacious researcher who specializes in explaining complex ideas to different audiences. I have a home network with 79 wired and wireless address.

I am told that my Sonos is causing the other addresses to drop off when sonos needs the speed. I am told a layer 3 switch will cure this problem Since the cost is very high I want to make sure i need this. This prevents Sonos from dropping other addresses.

If you go for layer 3 switch, you have to ensure that Sonos is on the same subnet. Layer 3 switch is an Ethernet switch that switches packets by looking at both their network address for example, their IP or IPX address and their physical address for example, their MAC address.

This type of switch operates at both the network layer layer 3 and the data-link layer layer 2 of the 7 layers OSI Model Open Systems Interconnection reference model. This kind of switch combines the speed of an Ethernet switch with some of the capabilities of a router for building advanced, high-speed Ethernet networks. These switches perform on two levels: layer 2 and layer 3. Their layer 3 switching functionality can take one of two forms:.