Resource Library

The most obvious difference is that hubs operate at Layer 1 of the OSI model while bridges and switches work with MAC addresses at Layer 2 of the OSI model. Hubs are really just multi-port repeaters. They ignore the content of an Ethernet frame and simply resend every frame they receive out every interface on the hub. The challenge is that the Ethernet frames will show up at every device attached to a hub instead of just the intended destination (a security gap), and inbound frames often collide with outbound frames (a performance issue).

That depends on their configurations. For example: While it makes very good sense to include redundant physical links in a network, connecting switches in loops, without taking the appropriate measures, will cause havoc on a network. Without the correct measures, a switch floods broadcast frames out all of its ports, causing serious problems for the network devices. The main problem is a broadcast storm where broadcast frames are flooded through every switch until all available bandwidth is used and all network devices have more inbound frames than they can process.

The key difference between hubs, switches and bridges is that hubs operate at Layer 1 of the OSI model, while bridges and switches work with MAC addresses at Layer 2 of the OSI model.

Software-defined networking (SDN) is a solution that will enable your organization to meet the demands of network programmability and automation. The result will be greater network agility to support new applications while complying with increasing security needs.

When properly utilized, VLANs and trunks provide flexibility, stability and ease of troubleshooting. This paper provides technical details about VLANs and trunks, along with design options at a basic to intermediate level. Recommendations and commands are included throughout.

Global Knowledge subject matter experts predict the top trends for 2020 in IT training, Microsoft, Cisco, AWS, cybersecurity and more.

Like it or not, Internet of Things (IoT) is upon us. There are a number of factors that will impact its adoption rate, and the inevitable privacy (or lack of) discussions will likely happen sooner than later. This is going to change the world as we know it, in many cases for the better. But we will need to keep an eye on the extent to which it invades our personal lives if it is going to be the positive force it has the potential to be.

As IT departments struggle with skills gaps and businesses attempt to recovery economically from the COVID-19 pandemic, these 10 IT skills are essential to drive success. Job roles in these areas pay well, but decision-makers are struggling to find qualified candidates. If you’re looking to make an IT skills investment or start a new career path this year, these are the areas to consider.

Switches play a vital role in moving data from one device to another. Specifically, switches greatly improve network performance, compared to hubs, by providing dedicated bandwidth to each end device, supporting full-duplex connectivity, utilizing the MAC address table to make forwarding decisions, and utilizing ASICs and CAM tables to increase the rate at which frames can be processed.

Instructor John Harmon continues his explanation of subnetting by showing how subnet masks can be used to sub-divide networks.