When Should You Use a Multiplexer or Switch?

Multiplexing is a valuable technique used by computer networking and telecommunications experts to combine multiple signals into one, saving physical channel resources. Commonly, multiplexers are brought up in the same context as mechanical switches because they perform similar functions. So what are the differences between multiplexers and switches, and in what situation would you choose one or the other? In this blog, we will discuss the similarities and differences between these two alike components.

Multiplexers are devices that take multiple input signals and combine them into a single signal for efficient transmission. The best and earliest example of multiplexing is the telephone line, which transmits a single multiplexed signal over long distances. Using this method, companies have saved on transmission costs and avoided the necessity of multiple mediums. Once the signal has reached the intended output, a demultiplexer will complete the inverse operation, breaking the signal into its various constituents.

Switches are used in similar applications as multiplexers but perform different operations. A good example of switching technology is a telephone service with 10 users. If one were to connect all the users with direct lines, they would require 45 separate lines. While such a configuration might seem reasonable at first, consider the millions of users in a modern telecommunication system and how many lines would be needed to support direct connections. If we were to implement a switching system in this example, the total number of lines would only be 5 since the switch could effectively link only the users needing to be connected.

With this understanding of multiplexers and switches, one can better understand the appropriate applications for both devices. First, we will examine the various applications in which a multiplexer can be used:

Communication Systems: In fiber-optic communication systems, multiplexers can be implemented to transmit audio and video data from different sources through a single channel.
Computer Memory: Multiplexers have played a tremendous role in reducing the physical space required inside a computer to maintain a large amount of memory. Additionally, multiplexers cut down on the total number of wires needed to connect memory components to other computer parts.
Telephone Networks: Modern telephone lines are generally inconspicuous thanks to multiplexers, which take thousands of audio signals and condense them into just a few lines.

In all cases, multiplexers make data transmission much more affordable by decreasing the number of transmission lines necessary and reducing the system's complexity. When choosing multiplexer components, one should consider the various specifications and options available.

First, it is important to determine the amount of bandwidth necessary for the intended application and compare it to the capacity of the multiplexer. Also, one must ensure that the multiplexer's channel count is sufficient for the application. For example, if one is looking to merge four input channels into a single line, it would not be as cost-effective to purchase a six-to-one multiplexer. Finally, with next-generation multiplexers promising bidirectional function, one may consider paying a higher upfront cost to obtain that technology.

Switches are generally easier to choose from, as there are fewer technical specifications. In general, selecting an appropriate switch comes down to the complexity of the network in question. For example, if one manages a simple network in which they do not need to isolate single ports, they could choose an unmanaged switch, which is a more cost-effective solution. Likewise, if one plans to expand their network in the future, they may be interested in a managed network switch, which has the same functionality as an unmanaged switch, while still providing support for more robust future networks.

Another type of switch gaining popularity due to its price point and simplicity is the power over Ethernet (PoE) switch. These newer devices can be electrically powered using a standard RJ45 Ethernet cable, which removes the necessity for a new power source to be installed. While a suitable choice for many applications, the maximum distance between any two pieces of connected equipment is <100m.

Regardless of network complexity, one must consider the maximum transfer speeds supported by each switch. In general, all applications under 1,000Mbps are compatible with switches that utilize RJ45 cables. Any network that demands greater transfer speeds, such as 10Gb/s, will require switches that are compatible with fiber optic transfer technology.

When you are in the market for high-quality switches and multiplexers, contact our team of experts at Stacked Hardware. Owned and operated by ASAP Semiconductor, we offer customers cost savings and unbeatable lead times on over 2 billion components for the aviation, defense, and IT industries. Additionally, as an AS9120B, ISO 9001:2015, and FAA AC 00-56B accredited distributor, we subject much of our inventory to rigorous quality assurance testing before shipping to screen for potential defects. Browse our expansive parts catalogs today and submit a quote at any time using our Instant RFQ service or by contacting our team by phone or email.