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More Bandwidth Isn’t Always the Solution

When your network slows down, taking advantage of network intelligence can be a more effective and affordable solution.

Nowadays, more small businesses have a converged network running three types of traffic simultaneously—voice, video, and data. Delay-sensitive and real-time applications such as voice and voice applications have different characteristics and requirements from those of traditional data applications. Because they are real-time-based, voice and video applications will only tolerate a small amount of delay affecting delivery. Voice and video traffic will also only accept a small amount of network error and jitter, both of which degrade the quality of the transmission delivered to the end user. To effectively transport voice and video traffic over a network, mechanisms are required that ensure reliable delivery of packets with low latency. In addition, more and more companies are running automated backups during regular work hours, so converged network can easily get bogged down, resulting in slow and spotty performance. A simple and easy solution may be to add more bandwidth, but that isn’t always the best fix. Instead, network intelligence features in your switch can improve network performance more effectively and affordably.

Network intelligence features, such as QoS, can be used to set priority levels for different types of traffic. Without intelligence, the network handles traffic on a first-come, first-served basis, regardless of the type of traffic or how critical it is to your business. Whatever traffic reaches the switch first is the traffic the switch sends along. All the traffic is treated equally and there’s no guarantee any one application will get the bandwidth it needs. Even if you add more bandwidth to the network, voice-over-IP (VoIP) calls can still drop, video streams can still hang, and data can slow to a crawl. When you prioritize traffic, you’re giving the network instructions on how to best handle the traffic flowing through your switch, both within your local network and to the Internet.

Making your network more intelligent

The easiest way to add network intelligence is to upgrade your unmanaged switch to a smart switch, like the Cisco 200 Series Smart Switches. A smart switch is essentially an entry-level managed Fast Ethernet or Gigabit Ethernet switch that gives you control over network traffic. It’s more affordable than a managed switch and much less expensive than upgrading a Fast Ethernet network to Gigabit Ethernet and switching from DSL or cable Internet to a T1 line. Smart switches provide basic network intelligence with Quality of Service (QoS), VLANs, and multicast management features.

QoS lets you give priority to traffic based on how important they are to your business operations as well as the amount of delay-sensitivity and bandwidth they require. In general, you’d configure the switch to give the highest priority to voice traffic, then video, then data. This ensures that voice traffic has  the guaranteed performance levels required for calls to remain clear and unaffected by less critical traffic.

You can also use VLANS to optimize your network performance. VLANs let you isolate different kinds of traffic into the same group on your network. You can separate voice traffic from regular data traffic by putting all voice devices in a dedicated “voice VLAN”. One advantage of using voice VLANs is that your voice devices do not have to contend directly with all the broadcasts and other traffic from data VLANs.

The third type of network intelligence is multicast forwarding, which lets the smart switch send the same data to multiple users simultaneously. If 10 employees need to watch the same online video at the same time, for example, multicast forwarding treats those video requests as a single request in a single stream of traffic, instead of 10 separate streams of traffic.

As your network traffic becomes more complex, you can get more advanced QoS, VLAN, and multicast management features in a managed switch, such as the Cisco 300 Series Managed Switches. A managed switch offers more granular control and lets you fine-tune your network performance with greater specificity to further optimize network performance.

What network bottlenecks are you experiencing?

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  1. There is only one of me trying to run a network and I would like some more information. We have consistently been adding more bandwidth and still have problems.