Jump to content
RESET Forums (homeservershow.com)
  • Network Basics-Part 1


    Dave
     Share

    Basic Network Principles Sermon

    A computer on your network is connected via a NIC, or Network Interface Controller. The NIC is the part of the computer where the network cable plugs in to. When your PC wants to send data, the NIC converts that data to a FRAME and sends the data through the cable. A frame consists of a Destination Address, a Source Address and then the data. In data networking, the concept of Media Access Control protocol, or MAC, provides a unique ID (or address) for each device. The address is 48-bit and symbolized by three, four hexadecimal groups. This address does not tell the actual location of your device, it just tells the unique MAC ID.

     

    clip_image002

     

    With these MAC addresses our NIC can create a frame. Once the frame is sent another NIC will see its own MAC address on the frame and then accept the frame also seeing the address of the sender. This is a very basic description but it suits us for the show.

     

    If you are sending data to another network your NIC makes a packet. A packet is different than a frame in that it also includes the Destination and Source Network Address in addition to the MAC addresses. The one thing to note is that the MAC address will change as it goes across networks. The network address will stay the same.

    Fast Ethernet

    The Fast Ethernet was introduced in 1995. This standard is at 100 Mbit/s. Remember that when we talk Mbit/s that the number needs to be divided by 8 to get megabytes. For example, I get 30 Mbit/s download from my ISP which equates to 3.75 megabytes per second download. This conversion means that the highest theoretical speed in a 100 Mbit/s network is 12.5 megabytes per second. In reality you would be lucky to get 75% of that.

    Gigabit Ethernet

    Finalized in 1998, Gigabit Ethernet is the now becoming mainstream for desktop PC manufacturers and for home enthusiasts around the world. 1000BASE-T, as the copper wiring spec is known, actually uses all four cable pairs to transmit data in both directions. The speed of Gigabit is 1,000 Mbit/s which converts to 125 megabytes per second. Again, you will never get that max number and will settle for up to 80% or so.

     

    http://www.10gea.org/1000base-t/

    Network cabling (non-fiber)

    Cat 5e cable is used for Fast Ethernet although you can get away with using it for Gigabit. Cabling for Cat 5e can go 328 feet.

     

    Cat 6 Cable is used for Fast, Gigabit and even 10-Gigabit Ethernet. Cabling for Cat 6 can go 300 feet while 10-Gigabit lengths are limited to 180 feet. This is more than enough for any enthusiast listening to this show.

    Switches

    The switch is a multiport complex device that acts as a bridge at the MAC address level. Switches allow you to segment the network and allow for greater network capacity.

     

    When the packet enters the switch the destination mac address the switch looks within the broadcast domain.

     

    As I start talking about this keep in mind that there are two addresses. There is a Source MAC address and a Destination MAC address. Think of an eight port switch you can buy at Fry’s or BestBuy. You connect each device into a port. The switch keeps a table of the MAC address of each device. When you send a frame, the switch can do one of three things: Flood, filter and/or forward.

     

    If the destination MAC is a broadcast address then the frame is sent to all ports except the sending port and this is called Flooding. Flooding also happens if the destination MAC address is NOT in the table.

     

    If the MAC address is the same as the sender then there is no reason to forward it and this is called Filtering.

     

    If the Destination MAC address is in the table the frame is sent to the proper port and this is called Forwarding.

     

    Unicast is sent and the CAM table finds the PC and just forwards to the port of the MAC address. When PC two replies the switch sends the data

    Switching Methods

    Store and Forward – Receives entire frame before switching and verifies addresses and error checks. Latency is an issue at times but this is going to be the most common for Linksys, Netgear and D-Link switches.

     

    Cut Through – Starts as soon as it sees the MAC address. No error check so end device has to check

     

    Fragment Free - Receives first 64 bytes before forwarding, this prevents collisions.

     

    The switch allows many workstations to transmit at the same time.

     

    Cisco offers a good set of training documents for anyone looking for more information. The link will be in the show post.

    Routers

    Expensive and setup intensive a router connects two or more devices on separate networks. Your router is what is needed to communicate with your ISP and determines the path when transferring data from one network to another. Your router will control access, port forwarding and other network specific settings. You can also have your router do policy-based routing which sets some rules for things like QOS for applications like VOIP and gaming apps. The main purpose of a router though is to connect your network to another network (internet) and forward packets to their destination. Routers do not care about the actual data in the packet and only look at the address. We heard last week though that you can build your own router and use software to create your own forwarding decision structure.

    References

    http://www.cisco.com/E-Learning/bulk/subscribed/tac/cim/iprouting/basic_ip_routing_concepts/mod_frameset.htm

     Share


    User Feedback

    Recommended Comments

    Great Network Basics Part 1 sermon, looking forward to the following sermons. Great addition to my Know How library. Would be great to know what software or hardware you recommend to check the LAN speed of a small home network?
    Link to comment
    Share on other sites

    I recommend LAN Speed Test, (LAN_SpeedTest.exe,) It is about 60KB in size and creates a new file each time to test upload and the read speeds. Default file size is 100MB, but you can make it whatever size you wish.
    Link to comment
    Share on other sites



    Create an account or sign in to comment

    You need to be a member in order to leave a comment

    Create an account

    Sign up for a new account in our community. It's easy!

    Register a new account

    Sign in

    Already have an account? Sign in here.

    Sign In Now

  • Our picks

    • I throw this out every once in a while.  Is anyone interested in writing up "semi-formal" reviews here on the forums?  I say semi-formal because they don't have to be pro level, just a good attempt at telling the story about the gear.  Something you have purchased lately.  You don't have to go buy stuff, just incorporate what you have already have purchased.  Hit me up with any questions.  You never know where it will lead!
        • Like
      • 3 replies
    • D-Link has dropped a couple of new products and additions to their lineup of smart home gear.  Hold on because there is a lot of gear!
      Let's start with cameras.  D-Link has new Wi-Fi cameras, the Full HD Pan and Tilt Pro Wi-Fi Camera (DCS-8302LH) and Full HD Indoor and Outdoor Pro Wi-Fi Camera (DCS-8526LH).  These are not just new, and good looking cams, they can now perform people detection and glass break detection.  The new cameras also feature expanded ways for customers to save video, including ONVIF Profile S, which enables custom storage and streaming options to personal NAS devices, built-in storage microSD capacity up to 256 GB, as well as free and paid cloud storage options. 
       

       
      This year's camera models include both an indoor and an outdoor model. The outdoor model features a spotlight and siren that can be triggered when motion is detected, deterring potential intruders. The indoor model pans around to give a full 360-degree view of any room and tracks motion. Both include two-way audio. 
      Full HD Pan and Tilt Pro Wi-Fi Camera is the model (DCS-8302LH), available in Q2, 2020, and retail pricing will be $99.99.
      Full HD Indoor and Outdoor Pro Wi-Fi Camera is the model (DCS-8526LH), available in Q3, 2020, and retail pricing will be $119.99.
      One of my favorite products is Wi-Fi.  D-Link has a whole lot of new products coming including Wi-Fi 6, Mesh, Alexa and Google Assistant integration, IFTTT, Parental Controls, and more!
       

       
      There are so many new SKU's that I can't make heads or tails of them!  I'm going to be speaking with D-Link more this week and will sort all of these out. I do want you to see all they are offering and what the release date and projected retail pricing will be.

      AC1900 Scalable Mesh Wi-Fi Router (COVR-1900-US), Q1 2020, $119.99
      AC1750 Mesh Wi-Fi Router (DIR-1750-US), Q1 2020, $99.99
      AC1900 Mesh Wi-Fi Router (DIR-1950-US), Q1 2020, $119.99
      AC1750 Mesh Wi-Fi Range Extender (DAP-1755-US), Q1 2020, $99.99
      AC1950 Mesh Wi-Fi Range Extender (DAP-1955-US), Q1 2020, $109.99
      Smart AX1500 Mesh Wi-Fi 6 Router (DIR-X1560-US), Q1 2020, $119.99
      Smart AX1800 Mesh Wi-Fi 6 Router (DIR-X1870-US), Q2 2020, $139.99
      Smart AX2400 Mesh Wi-Fi 6 Router (DIR-X2460-US), Q3 2020, $159.99
      Smart AX5400 Mesh Wi-Fi 6 Router (DIR-X5460-US), Q1 2020, $279.99
      AX1800 Mesh Wi-Fi 6 Range Extender (DAP-X1870-US), Q2 2020, $129.99
      AX1800 Whole Home Mesh System (COVR-X1872-US), QX22020, $269.99
        • Like
      • 0 replies
    • RESET Merch Shop
      Get ya Merch here!  I've created a T-Shirt shop with the famous RESET paperclip. I've pasted that clip on just about everything so you can wear it around town!  Cable bags, Coffee Mugs, T-Shirts, and more. 
       
      https://reset.threadless.com/
       
      or you can get it it via
       
      https://reset.fm/store
       
      Here is the main design.
       

       
      Below is a part of the order that I put in!  
       
       

       
      The Heather Grey above is the Extra Soft version and it is awesome.  I highly recommend the softness!    The "Chili Red" is the Tri-Blend and probably my favorite feel and color.

       
      This is the Zip-Up Hoody, Heather Indigo, Sponge Fleece, Men's, Large.  In my podcast I couldn't remember what style it was but it is Sponge Fleece. It's REALLY soft on the inside. Soft outside as well. The only problem is with the zip up hoody the logo is on the back. Regular hoody, it will be on the front.
       
      https://reset.threadless.com/
       
      or you can get it it via
       
      https://reset.fm/store
       
      Thank you for supporting this community. Everything you purchase will help keep the lights on the hard drives spinning.
       
      • 0 replies
    • OneDrive Personal Vault and expandable storage
      Microsoft's OneDrive has a few new features and options worth pointing out.  Personal Vault and Expandable Storage.
       
      Personal Vault is a protected area in OneDrive that can only be accessed with a strong authentication method or a second step of identity verification, such as your fingerprint, face, PIN, or a code sent to you via email or SMS. 
       
      Personal Vault gives you an added layer of protection for your most important files, photos, and videos—for example, copies of documents such as your passport, driver’s license, or insurance information—should someone gain access to your account or device.
      Plus, this added security won’t slow you down. You can quickly access your important documents, photos, and files with confidence wherever you are, on your PC, OneDrive.com, or your mobile device.

       
      Beyond a second layer of identity verification, Personal Vault also includes the following security measures:
       
      Scan and shoot—Using the OneDrive app, you can scan documents or shoot photos directly into your Personal Vault, keeping them off less secure areas of your device, like your camera roll.
      Automatic locking—No need to worry about whether you left your Personal Vault or your files open—both will close and lock automatically after a period of inactivity.
      BitLocker encryption—On Windows 10 PCs, OneDrive automatically syncs your Personal Vault files to a BitLocker-encrypted area of your local hard drive.
      Restricted sharing—To prevent accidental sharing, files in Personal Vault and shared items moved into Personal Vault cannot be shared.
       
      Taken together, these security measures help ensure that Personal Vault files are not stored unprotected on your PC, and your files have additional protection, even if your Windows 10 PC or mobile device is lost, stolen, or someone gains access to it or to your account.
       
      Expandable Storage
       
      If you are and Office 365 Subscriber you get 1 TB of OneDrive storage space with all the other Office goodies like Word, Excel, etc.  I know personally that I have gone over the 1TB limit and have always wanted to be able to add additional storage to my account.  Now you can!

       
      Pick and option and keep on hoarding, errr, I mean saving! Cancel anytime, upgrade at any moment.
      • 1 reply
    • Ubiquiti adds new items to the Unifi Line including UAP Flex HD and the Unifi Dream machine
      Ubiquiti has been busy.  There area ton of new items to recently released and I'm going to share two of my favorites.
       
      The UAP Flex HD and the Unifi Dream machine. The Flex HD is a mouthful of descriptors like most of UI gear is.  It's a 2Ghz 2x2 MIMO, 5GHz 4x4 MU-MIMO, POE, Indoor/Outdoor, multi mount, mesh point that is no bigger than a can of Coke.

       
      You will still need the Unifi controller although you can configure it with basic functionality with the Unifi App.  I've always found it's best to configure with your controller and then use the app as an add-on.  There are several mounting options that include sitting it on a shelf! That is something that Unifi has not had before unless you count the ceiling AP I have awkwardly mounted placed on top of a few books.  It can be found on the Unifi store for $179.
       
      https://store.ui.com/collections/wireless/products/unifi-flexhd
       
      The Dream Machine is an altogether different beast that I hope lives up to its naming.  This is the gateway drug, for lack of a better term, to the Unifi world.  The starter kit.  It is an Access Point, Gigabit Switch, Security Gateway, and the Cloud Key all in one package.  The latter being the most significant as this is something that has deterred new users from getting started with Unifi.  Requiring new users to purchase a $100 item just to run the AP's has been somewhat of a roadblock in the past.  Granted, that is improving every year with the ability to run it in the cloud, on a NAS, a Pi, Docker, MacOS, and of course Windows, it is still a barricade to getting up and running when manufacturers such as Eero offer simplicity in an app.
       

       
      The switch includes 4 LAN Ports and 1 WAN port.  All of which are Gigabit and security services such as IPS are rated at Gigabit speed. It's $299 in the Unifi store but I'm unsure how nicely it will play with other Unifi gear.  This may be a nice "first AP" with its built in Cloud Key if you can add additional units or other Unifi access points.
       
      https://store.ui.com/collections/routing-switching/products/unifi-dream-machine
      • 4 replies
×
×
  • Create New...