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HTG Explains: Understanding Routers, Switches, and Network Hardware

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Today we’re taking a look at the home networking hardware: what the individual pieces do, when you need them, and how best to deploy them. Read on to get a clearer picture of what you need to optimize your home network.

When do you need a switch? A hub? What exactly does a router do? Do you need a router if you have a single computer? Network technology can be quite an arcane area of study but armed with the right terms and a general overview of how devices function on your home network you can deploy your network with confidence.

Understanding Home Networking Through Network Diagrams

Rather than start off with a glossary of networking terms—and in the process slam you with a technical terms with no easy point of reference—let’s dive right into looking at network diagrams. Here is the simplest network configuration available: a computer linked directly to a modem which is in turn linked through a phone line/cable/fiber optic uplink to the individual’s internet service provider.

2011-11-29_114329

It doesn’t get less complicated than this arrangement but there is a price to pay for the ultra-simplicity of the setup. This user cannot access the internet with a Wi-Fi device (thus no access for smart phones, tablets, or other wireless devices) and they lose out on the benefits of having a router between their computer and the greater internet. Let’s introduce a router and highlight the benefits of using one.  In the diagram below we’ve introduced two elements to the network: a wireless router and a laptop connecting to the network via that wireless connection.

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When should you use a router? Given the low cost of home routers and the benefits gained from installing one on your network you should always use a router (which almost always includes a firewall feature).

Home routers are actually a a combination of three networking components: a router, a firewall, and a switch. In a commercial setting the three pieces of hardware are kept separate but consumer routers are almost always a combination of both the routing and switching components with a firewall added in for good measure. First let’s look at what the router function does.

At the most basic level a router links two networks together, the network within your home (however big or small) and the network outside your home (in this case, the internet). The broadband modem provided to you by your ISP is only suited to linking a single computer to the internet and usually does not include any sort of routing or switch functionality. A router performs the following functions:

  • IP sharing: Your ISP assigns you one IP address. If you have a desktop, a laptop, a media box on your TV, and an iPad, that one IP address clearly isn’t going to cut it. A router manages those multiple connections and ensures that the right packets of information go to the right places. Without this function there would be no way for a person on the desktop and a person on the laptop to both browse the web as their would be no distinguishing between which computer was requesting what.
  • Network Address Translation (NAT): Related to the IP sharing function, NAT modifies the headers in packets of information coming into and out of your network so that they get routed to the proper device. Think of NAT like a very helpful receptionist inside your router that knows exactly where every incoming/outgoing package should go and stamps the department on them accordingly.
  • Dynamic Host Configuration: Without DHCP you would have to manually configure and add all the hosts to your network. This means every time a new computer entered the network you would have to manually assign it an address on the network. DHCP does that for you automatically so that when you plug your XBOX into your router, your friend gets on your wireless network, or you add a new computer, an address is assigned with no human interaction required.
  • Firewall: Routers act as basic firewalls in a variety of ways including automatically rejecting incoming data that is not part of an ongoing exchange between a computer within your network and the outside world. If you request a music stream from Pandora, for example, your router says “We’re expecting you, come on in” and that stream of data is directed to the device that made the request. On the other hand if a sudden burst of port probing comes in from an unknown address your router acts as a bouncer and rejects the requests, effectively cloaking your computers. Even for a user with a single computer a simple $50 router is worth it for the firewall functionality alone.

In addition to the inside-to-outside network functionality outlined above, home routers also act as a network switch. A network switch is a piece of hardware that facilitates communication between computers on an internal network. Without the switching function the devices could talk through the router to the greater internet but not to each other—something as simple as copying an MP3 from your laptop to your desktop over the network would be impossible.

Most routers have 4 Ethernet ports which allow you to plug in 4 devices and have them communicate via the switch function. If you need more than 4 Ethernet connections you’ll need to upgrade to a router with a larger port bank (a rather expensive proposition that will usually only boost you up to 8 ports) or you can pick up a dedicated switch. Note: You only need to upgrade if you’re running out of physical ports for hard line connections. If you only have one computer and one networked printer plugged into your 4 port router (and everything else on your network is Wi-Fi based) there is no need to upgrade to gain physical ports. That said, let’s take a look at a network with a dedicated switch.

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Although the 4-port limit on the super majority of home routers was more than enough for most home users, the last 10 years have brought a significant increase in the number of networkable devices within the home. It isn’t uncommon to have multiple computers, multiple game consoles, media centers, printers, file servers, and more that all connect to the Ethernet LAN (while you may get away with putting your Wii on the Wi-Fi network for things like dedicated video streaming and media server access it is much preferable to have a hard line connection). Once you’ve reached that level of device saturation it’s necessary to add in a switch with 8, 16, or more ports to properly support your growing home network.

As a side note, historically people often relied on hubs because they were so much cheaper than pricey switches. A hub is a a simple network device that does not examine or manage any of the traffic that comes through it—it’s a “dumb” network device—by contrast switches actually interact with the data packets and actively direct them. Because hubs have no management component there are frequent collisions between packets which leads to an overall decrease in performance. Hubs suffer from a number of technical shortcomings which you can read about here. Consumer grade networks switches have fallen in price so steeply over the last 10 years that very few hubs are even manufactured anymore (Netgear, one of the largest manufacturers of consumer hubs, no longer even makes them). Because of the shortcomings of network hubs and the low prices of quality consumer-grade network switches we cannot recommend using a hub. When you can pick up a perfectly good high-speed 8-port switch for $25 there’s no good reason to use an outdated hub on a home network—if you’re curious why a network admin would ever deploy a hub you can read about it here.

Returning to the topic of switches: switches are an excellent and inexpensive way to increase the size of your home network. If you outgrow the bank of 4 ports on the back of your router the simplest thing you can do to expand your network is to purchase a switch with an appropriate number of ports. Unplug the devices from your router, plug all the devices into the switch, and then plug the switch into the router. Note: switches have absolutely no routing functionality and cannot take the place of a router. Your router likely has a 4-port switch built into it but that does not mean your new 8-port dedicated switch can replace your router—you still need the router to mediate between your modem and switch.

Decoding Network Speed Designations

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Now that you’ve got a clear picture of how exactly your network should be physically configured let’s talk about network speeds. There are two primary designations we are interested in: Ethernet and Wi-Fi. Let’s take a look at Ethernet first.

Ethernet connection speeds are designated in 10BASE. The original Ethernet protocol, now 30 years old, operated as a max speed of 10 Mbit/s. Fast Ethernet, introduced in 1995, upped the speed to 100 Mbit/s. Gigabit Ethernet was introduced shortly after that in 1998 but didn’t gain much traction in the consumer market until recently. As its name suggests, Gigabit Ethernet is capable of 1000 Mbit/s. You will commonly see these designations noted on networking gear and its packaging as 10/100 or 10/100/1000 indicating which Ethernet version the device is compatible with.

In order to take full advantage of the maximum speeds all the devices in the transfer chain need to be at or above the speed rating you want. For example, let’s say you have a media server in your basement with a Gigabit Ethernet card installed and a media console in your living room with a Gigabit Ethernet card but you are connecting the two together with a 10/100 switch. Both devices will be limited by the 100 Mbit/s ceiling on the switch. In this situation upgrading the switch would boost your network performance considerably.

Outside of transferring large files and streaming HD video content across your home network there is little need to go out and upgrade all your equipment to Gigabit. If your primary computer network usage involves browsing the web and light file transfers 10/100 is more than satisfactory.

Understanding Wi-Fi Speeds

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Wi-Fi speeds are designated by letter, not by number. Unlike the easy to translate number-as-network-speed designation we find with Ethernet the Wi-Fi designations actually refer to the draft versions of the IEEE 802.11 networking standard that dictates the parameters of the Wi-Fi protocol.

802.11b was the first version widely adopted by consumers. 802.11b devices operate at a maximum transmission of 11 Mbit/s but the speed is highly dependent on signal strength and quality—realistically users should expect 1-5 Mbit/s. Devices using 802.11b suffer from interference from baby monitors, bluetooth devices, cordless phones, and other 2.4GHz band devices.

802.11g was the next major consumer upgrade and boosted the max transmission to 54 Mbit/s (realistically about 22 Mbit/s accounting for error correction and signal strength). 802.11g suffers from the same kind of 2.4GHz band interference that 802.11b does.

802.11n is a significant upgrade to the Wi-Fi standards—devices use multiple-input multiple-output antennas (MIMO) to operate on both the 2.4GHz and relatively empty 5GHz bands. 802.11n has a theoretical maximum of 300 Mbit/s but accounting for error correction and less than ideal conditions you can expect speeds in 100-150 Mbit/s range.

Like Ethernet, Wi-Fi speeds are limited by the weakest link in the direct network. If you have an 802.11n capable Wi-Fi router but your netbook only has an 802.11g capable Wi-Fi module you will max out at the 802.11g speeds. In addition to the speed limitations there is a very pressing reason for abandoning the oldest popular Wi-Fi protocol 802.11b. You must use the same level of encryption on every device in your network and the encryption schemes available to 802.11b devices are weak and have been compromised (WEP encryption, for example, can be compromised in a matter of minutes by a moderately skilled child). Upgrading your Wi-Fi router and wireless equipment allows you to upgrade your wireless encryption as well as enjoy faster speeds. If you haven’t done anything to secure your router now would be a good time to read our guide to locking down your Wi-Fi network against intrusion.

Also like Ethernet, upgrading to the maximum speed—in this case 802.11n—is best suited for people moving large files and streaming HD video. Upgrading to 802.11n will have a negligible impact on your web browsing speed but will have an enormous impact on your ability to wirelessly stream HD content around your home.


At this point you’ve got a handle on how your home network needs to be laid out and you have an understanding of what the network speed designations mean and how they impact you and your network. It’s time to upgrade your switch, roll out some new Wi-Fi bandwidth, and enjoy a better optimized home network.

Jason Fitzpatrick is warranty-voiding DIYer and all around geek. When he's not documenting mods and hacks he's doing his best to make sure a generation of college students graduate knowing they should put their pants on one leg at a time and go on to greatness, just like Bruce Dickinson. You can follow him on if you'd like.

  • Published 11/29/11

Comments (39)

  1. chess

    cool always good to review this stuff.

  2. Koni

    Great article and good introduction. One question: let’s say you need to add more ports to a network but it is in a room that only has one cable running to it. can you use the four ports on the back of the router and them put a switch in the room you need more ports? Meaning that not all devices would be plugged into the switch. While I know this works as I have done it is this a good setup?

  3. Markie

    Great you just summed up most of what I leanred in cisco last year haha anyways this is a great introduction to networking

  4. hydroment

    It is not necessarily a bad thing. But at the same time not necessarily a good thing. It depends on which devices are communicating with each other more frequently and with what volume of bandwidth. Say you have a home video server, kitchen recipe wi-fi laptop, kid’s school work computer, and smart home thermostat all connected to the router, leaving one port to attach a switch. To the switch you have connected a network capable plasma TV, network printer, Dad’s computer (downloading loads of freeware) and Xbox 360 for the kid. This would all be connectable, but the problem is in that there is the potential of bottlenecking the single lan segment to the switch, while there is little traffic between the ports on the router. If dad starts downloading an ISO copy of Ubuntu Ultimate Gamer Ed.(25Mbps cable), at the same time Mom starts streaming Hope Floats in 1080p (35Mbps) from the video server, and Jr. starts playing WOW online (lots of data packets) and little Suzy printing her school report of 25 page full page full color to the networked printer, there is the potential the Xbox game could lag or the video could lag, or worse, someBODY could nag.

    If the Xbox, WiFi, school work computer, switch 1 and switch 2 were to be on the router, and the TV, Video Server were on switch 1, Dad’s computer, networked printer and smart thermostat on switch 2, bottlenecking could be minimized. Think of which devices talk with each other and what type of data is to be sent. Is the data in large chunks or is it a series of small data packets that each one needs to be read and handled? The tv and the video server are a likely pair. Xbox communicates with those outside the LAN, so put it closest to the ‘door’ on the router. Don’t add extra traffic control for the series of data packets to a switch that the router can handle. If connected to a switch, the data has to be handled twice (switch and router).

    In the scenario above, switch 1 has 2 devices. switch 2 has 3 devices. to further minimize bottlenecking, connect switch 1 to switch 2. this will give for an alternate path for the data if one route is busy.

    As stated above, upgrading (if not already in place) to a Gbit LAN would also aid in minimizing the problems.

  5. Nick S.

    @chess: Yes, you can do it up to seven times deep (your example consisting of twice).

  6. Zbigniew

    It is a great article. Good for many to see how to set up network at their home.

    However, I would suggest one more solution to extend the physical ports.

    As you said, we need router (with 4 ports – typical one). Probably it is with Wireless N (lately it is most common) – so I bought one to have fast transmition.

    So what I did.
    I counted that in one room I have Media Center, BD player, CABLE and SAT.

    In other room I have server computer (put in wardrobe), usb printer, usb scanner, sometimes laptop.

    So,
    I used my two old …. routers that I used before (one N and one G).
    Thus,
    The main router is the G router (I switched of the Wireless here). (DHCP activated)
    To this router is connected:
    1) Cable TV,
    2) Sat TV,
    3) Router nr 2 (WLAN port)
    4) TV

    Router nr 2 is the new N one. (used Wireless WPA2) (DHCP activated)
    Connected:
    1) BD player,
    2) Home Receiver
    3) Router nr 3 (Port 1)
    4) TV in other room

    Router nr 3 is the old N one. (used Wireless WPA2 – same as in router nr 2) (DHCP and Firewall not activated)
    Connected:
    1) Router nr 2
    2) Server
    3) Laptop
    4) USB spliter (connected to it printer and scanner).

    Works perfectly.
    All devices that I want are in my private network which is after 2 firewalls in routers.
    Switch does not have firewall as I know.

    Additional benefit is that I have extended Wireless range. It means: when I am in saloon my mobile phones use router nr 1, however if I go to bedroom mobile phones automatically switch to router nr 2 as mobile will have better signal (and it keeps the same IP).

    So, I wrote it all, as I think it would be nice to mention such configuration in your description, as even additional benefit is that many people have old routers – and people does not know how to use them.

    Best Regards

    Zbigniew Wasik

  7. Cat McGowan

    A great article for enlightening networking novices.

    Did anyone notice in the photo of the 8P8C connector the wires are not terminated per the color codes of either the T568A or T568B standard?

  8. Jim Stevens

    Thanks,Good info I can understand,

  9. Sliaf

    Great article. A lot of information for home users.

    Correct me if I am wrong but dual band wireless N can support 600 Mbit/s, you only have it listed at 300 Mbit/s.

  10. Osmosis

    As my noob, I think my system may be seriously lacking.
    My setup is as follows:

    DLS WiFi modem/router (I believe)> 4 port switch> 2 PCs.

    I use the WiFi for laptops, Xbox, Wii, kids DSi. My switch must not be a network switch, I can’t transfer files between my two PCs. I think I have a “dumb” switch/Hub.

    Should I replace the ISP provided modem/router with an aftermarket item? And, replace my hub with a network switch?

    I have a printer and I would like it to be able to use it for both computers. I currently have to unplug and plug in the USB into the computer I want to print from.

  11. Paulo Cezar

    Great article. Very well written and direct to the point.

  12. ridgerunner114

    This is a very good well written article that shows clearly how to set up a home network.

    Thanks

  13. Joseph

    This is really good, in fact i love this, now i can answer some technical interview questions. Great work done!

  14. Michael

    Excellent post. It’s just what I needed exactly when I needed it. It’s off to the store for a switch. Thank you.

  15. Michael (2)

    Thank you so much. Now where do I find out how to successfully connect the network at my house (with a server) to the network at my mom’s house (with a server) so that both can be managed from one spot? I’ve tried to understand VPN, configuring a secondary domain controller, etc., but all I’ve ended up doing is messing up DNS badly and taking down one or both each and every time! HELP!!! ;)))

  16. zenpistolero

    I love the wiring in the cable connector pic. Is that a new standard I wasn’t aware of? Is this the new fashion season where stripes and solids go together? After crimping many thousands of those, when it’s wrong like that it might as well be flashing in neon.

    At least pins 3-6 and 4-5 are on pairs. I was troubleshooting an intermittent connection at a school that had me stumped until the teacher asked if the cable they had made was too long. The length wasn’t what caught my attention. Turns out he had been very careful to keep the pairs together. Chalk another one up to Layer 0.

  17. les

    wow – I understood that. Thanks

  18. randy kaiser

    Question: I have a modem, wireless router with blu-ray player,printer, ps3, amd dwsktop computer ,

    Should I connect the computer directly, (non wireless) for best results, instead of using the the reature of wireless?
    Thanks Randy

  19. bigrips

    Great article…. lots in useful info.

    I’m a bit of a networking novice, but this helped make sense of a lot of it.

    Question for you… Will buying a newer “N+” router, with QOS help with HD video streaming?

    I’ve got a couple HTPC’s running XBMC in the house… another great HTG article:

    http://www.howtogeek.com/72267/how-to-turn-your-computer-into-a-supercharged-tivo-with-sick-beard/

    One machine is connected via ethernet (and has the network drives connected via USB 2.0) and the other HTPC is connected via wi-fi and has the network drives added as video sources (SMB) in XBMC.

    The wi-fi machine (i3 4GB ram) stalls on even some SD video playback or loses wi-fi signal pretty often, even when nothing is downloading.

    I’m not doing any gaming on the network, and consistently get crazy download speeds on the machine connected via ethernet.

    The router is an N router (Belkin N Wireless router)

    Any idea why the wi-fi HTPC is having issues? Time for a newer “N+” router?

    Thanks,

  20. Jireh Ladera

    Great article! A very simplified approach! Love it! I now understand it more. :)

  21. Vysakh

    I was reading Networking for Dummies to learn basics of networking. Your article saved my time by skipping many pages. Also please explain how to transfer files among two connected to a router.

  22. Wayneluke

    @Silaf

    The way I understand it is that the bandwidth of your Wireless-N router is determined by the number of antenna on the device. Each antenna gives you 150 Mbps at optimal use. Most consumer devices come with two antenna which would limit you to 300 Mbps. Some like the Apple Airport have 3 antenna which give you 450 Mbps total bandwidth. However even if you find a router with 4 antenna, your individual devices probably won’t be able to take advantage of the all that bandwidth.

    Great article. Should follow up with bridging wireless routers and dealing with multiple-floor dwellings and radio interference.

  23. William R. (Bill) Harvey

    I have a Netgear 108 Mbps wireless firewall router WGT624v2 connected just as you show in your second simple diagram except there’s no computer direct connection: it’s just cable modem to wireless router. It is in an apartment for use of 3 students who need internet access for schoolwork. The problem is that the wi-fi doesn’t want to stay up. When I had it in my home connected to my computer by LAN cable, and wi-fi connection to my laptop, I frequently had log in to the router from my computer, examine the settings without changing any, and the laptop wi-fi connection would come up. Is this a characteristic of routers, or the Netgear in particular, or am I doing something wrong? Any ideas?

  24. SamF

    I still don’t know how to communicate between two computers (laptops using Win7/64) on my network. If it was covered in the article I missed it both times I read it. i need help with that. thanks

  25. dima

    great summary of basic home networking, very useful

  26. Matt

    PAT NOT NAT

  27. zarnaik

    This is the kind of things I love to learn about :)

  28. kasey

    good article. I have 2 questions: I have a desktop plugged into a router (n), then a modem. I use laptop and netbook wirelessly in other room, and am getting ready to hook up roku 2 wirelessly. Should I be able to communicate between computers? and how can I plug my usb printer into network so I can print to any room? Do I need a special cable to go from the printer (usb) to a ethernet port? Thanks

  29. raullllll

    i tried using a four port switch to connect my xbox and several computers and kept on getting a “conflicting IP adress” message.

  30. John

    Casey – you can’t plug a USB only printer into the network. You either have to leave it on one of the computers, which is OK but you must leave that computer on all the time in case someone wants to print, or buy a printer Ethernet adapter. They come in two flavors, one that attaches only to an Ethernet port, so must be near the switch, or one which has wireless and can be placed anywhere your wireless LAN can be reached. New printers usually have an option to have that device built-in.

  31. John

    Raullll – you need a device to manage DHCP to assign different addresses to each device, or do it manually. In your case, I would set each device manually to its own unique address, like 192.168.100.1 for the first, 192.168.100.2 for the second, and so on. Notice that those addresses are with in the range used for personal LAN devices.

  32. John

    William R. (Bill) Harvey – You shouldn’t have to log in the router and make changes once it is correctly configured. I would first suspect that you have interference on the channel that you have assigned to the router. There are 11 channels and, for some stupid reason, or none at all, manufacturers seem to pick either channel 1 or 6 99% of the time. I have an app in my Android phone which looks at the WiFi activity in the area and shows which channels are being used. I then switch the router to an unused channel. Microwave ovens and 2.4 GHz telephones also interfere with WiFi.

  33. Jim Stevens

    I like many of your articles and would like to print them. Would you please give us an option to print the articles? Thanks

  34. John

    Orange Stripe, Orange, Green Stripe, Blue, Blue Stripe, Green, Brown Stripe, Brown … Right?

  35. Stef

    Pay attention when switching your router to 802.11n, some wireless network cards do not support this standard ! So no conections possible at all, go to your router with a laptop and reset the configuration to support all standards. Greatings. Stef.

  36. Art Kennedy

    This is good stuff. I think I now understand that I cannot create a network of my local devices that uses the router to communicate. Is that right? Is it possible for my wi-fi enabled desktop to comm directly with my netbook, my kindle. Is that an ad hoc network? Do you have an article on that?

  37. Syed Arif

    Great Aritcel I love it .

  38. Frank B

    Great article…well written! My router/modem connected to the desktop is on one side of the house on the 2nd floor (and cannot be moved), and the HD tv is on the opposite side of the house on a lower floor. How do I improve the wireless connection speed and/or signal strength to improve streaming capabilities of the tv? Running a super long ethernet cable through the house is not a good idea, either.

  39. Pam Hartsfield

    I have a question. Would a person have another reason for installing a router not issued by their internet company? Does a router inable one computer to see what the others are doing that is hooked up to the router?? My friend wanted to put a router in my house. I told him my internet company offered routers at $25 and he? said he would rather purchase his own so he could control it. What did he mean by this? I’m just a little suspicious why he wants to install a router in my house. I’m not having trouble getting the internet. all I have is a computer and a tablet. Will this router enable another person if they are somewhere else see what I do on the computer. That is , if he wishes to????

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