Switching Technology
Another approach to pushing beyond the limits of Ethernet technology is the development of switching technology. A switch bridges Ethernet packets at the MAC address level of the Ethernet protocol transmitting among connected Ethernet or Fast Ethernet LAN segments.
Switching is a cost-effective way of increasing the total network capacity available to users on a local area network. A switch increases capacity and decreases network loading by dividing a local area network into different segments, which don’t compete with each other for network transmission capacity.
The switch acts as a high-speed selective bridge between the individual segments. The switch, without interfering with any other segments, automatically forwards traffic that needs to go from one segment to another. By doing this the total network capacity is multiplied, while still maintaining the same network cabling and adapter cards.
Switching LAN technology is a marked improvement over the previous generation of network bridges, which were characterized by higher latencies. Routers have also been used to segment local area networks, but the cost of a router, the setup and maintenance required make routers relatively impractical. Today switches are an ideal solution to most kinds of local area network congestion problems.
VLAN (Virtual Local Area Network)
A VLAN is a group of end-stations that are not constrained by their physical location and can communicate as if a common broadcast domain, a LAN. The primary utility of using VLAN is to reduce latency and need for routers, using faster switching instead. Other VLAN utility includes:
Security, Security is increased with the reduction of opportunity in eavesdropping on a broadcast network because data will be switched to only those confidential users within the VLAN.
Cost Reduction, VLANs can be used to create multiple broadcast domains, thus eliminating the need of expensive routers.
Port-based (or port-group) VLAN is the common method of implementing a VLAN, and is the one supplied in the Switch.
Features
24×10/100Mbps Auto-negotiation Fast Ethernet RJ45 ports
2×10/100/1000Mbps Auto-negotiation Gigabit RJ45 ports
2×mini-GBIC ports(shared with two Gigabit RJ45 ports)
All RJ45 ports support Auto-MDI/MDIX, so there is no need to use cross-over cables or an up-link port
Full/half-duplex transfer mode for 10/100Mbps RJ45 port
Full-duplex transfer mode for Gigabit port
Wire-speed reception and transmission
Store-and-Forward switching scheme capability to support rate adaptation and ensure data integrity
