Traditional network infrastructures relied on one or two routers in the core. The network was then designed around these core routers. This failed to solve the problem of scalability because software-based routers have limited capacity and port density. They also introduced a potential bottleneck in the network (if the router was incapable of routing the many requests at one given port).

Yesterday's legacy routers with their limited packet forwarding schemes cannot keep up with new web applications. They are slow, expensive, difficult to manage, and often use proprietary routing protocols. They were designed to support yesterday's predictable traffic patterns instead of today's random, megabyte-intensive data flows.

Due to the costs of these routers, networks were designed with a few routers doing all the work. This led to ineffective isolation of networks and stressed ports on the routers. For example if multiple VLANs were logically connected via switches to the ports of a Cisco 2621, the one port (acting as a gateway to the internal network) would be limited to 100Mbps total bandwidth for all VLANs. Considering there are typically more then 6 different VLANs (when network properly isolated) that is 600Mbps of potential data at any one given time the router has to deal with. Resulting in the router becoming a bottleneck and dropping any packets it cannot handle.

At Interspots we use full Layer 3 routing web switches from Extreme Networks.

Layer 3 switching is routing in hardware. Traditional software-based routers forward in the 500,000 packets per second range. Layer 3 switches forward up to 48 million packets per second. Although they both route packets, the integration of forwarding using high-speed ASIC technology differentiate Layer 3 switches from traditional software-based routers.

500,000 packets might seem a great number, until you take into consideration that web hosting companies host hundreds to thousands of separate sites, and with packets all having to go through a software router things start to get congested.

Layer 3 insures that all your important packets of information between the web servers and the Internet have the fastest possible route and no slowdowns.

L3 switching incorporates a meshed backbone, meaning that all ports are connected to all other ports. Unlike costly software routers, there is no point of failure.

For example, a 48 port Layer 3 switch is equivalent to 48 traditional 2 port routers with 1 of each port connected to 8 computers and the 2nd port of each router would all have to be connected together. Realistically, 48 routers are very expensive and impractical.