A high-availability router attached to the backbone frame switch moves traffic between virtual LANs.
In a frame-based virtual collapsed backbone, workgroup- level frame switches replace (or assist) overtaxed shared-media hubs and ease desktop bottlenecks.
But unlike a conventional bridge, which transfers packets by way of shared memory or an internal bus, a frame switch is built around a high-speed switching fabric.
Replacing a shared-media hub with a frame switch divides the LAN into multiple segments and gives each segment full LAN bandwidth.
Few organizations require full LAN bandwidth to every desktop, so the most common place to install a frame switch is behind a shared-media hub.
Like a frame switch, this device interfaces directly to traditional LANs and is transparent to existing applications and network operating systems (NOSs).
Frame switches, also known as LAN switches, offer the performance boost of LAN segmentation without consuming router ports and without requiring new NICs.
Cell switches differ from frame switches in two important ways:
Today, when phone companies have over-committed their frame switches
, the maximum CIR, which is 1.1 mbps out of the total, is probably a safer investment to preserve your share of bandwidth.