Today we're going to delve into the different hardware associated with networks; we're going to point towards the small business/home networking class, so I'll leave quite a few of the corporate items out as it won't be applicable to most people reading this short guide.Routers
- A router is simply a device which allows multiple systems to connect to the internet, while utilizing a single IP Address; basically, it's a simple way of sharing your internet connection.
There are two types of Routers:
- Wireless - A Wireless Router will allow you to serve your internet access to your computers by way of Wireless Networking (each system will need its own Wireless Card to "wirelessly" talk to your router, please note that you can "wire" the system to your network and it can talk to other systems in your network which are connected wirelessly).
- Wired - A standard Wired router will act the same as the wireless router above only with wired only clients.
These days, you'll likely be in the market for a Wireless Router, the different Wireless Specifications for WiFi are:
- 802.11a - Originally described as clause 17 of the 1999 specification, the OFDM waveform at 5.8 GHz is now defined in clause 18 of the 2012 specification, and provides protocols that allow transmission and reception of data at rates of 1.5 to 54 Mbit/s. It has seen widespread worldwide implementation, particularly within the corporate workspace. While the original amendment is no longer valid, the term 802.11a is still used by wireless access point (cards and routers) manufacturers to describe interoperability of their systems at 5 GHz, 54 Mbit/s.
- 802.11b - The 802.11b standard has a maximum raw data rate of 11 Mbit/s, and uses the same media access method defined in the original standard. 802.11b products appeared on the market in early 2000, since 802.11b is a direct extension of the modulation technique defined in the original standard. The dramatic increase in throughput of 802.11b (compared to the original standard) along with simultaneous substantial price reductions led to the rapid acceptance of 802.11b as the definitive wireless LAN technology.
- 802.11g - In June 2003, a third modulation standard was ratified: 802.11g. This works in the 2.4 GHz band (like 802.11b), but uses the same OFDM based transmission scheme as 802.11a. It operates at a maximum physical layer bit rate of 54 Mbit/s exclusive of forward error correction codes, or about 22 Mbit/s average throughput. 802.11g hardware is fully backward compatible with 802.11b hardware, and therefore is encumbered with legacy issues that reduce throughput by ~21% when compared to 802.11a.
- 802.11n - 802.11n is an amendment that improves upon the previous 802.11 standards by adding multiple-input multiple-output antennas (MIMO). 802.11n operates on both the 2.4 GHz and the 5 GHz bands. Support for 5 GHz bands is optional. Its net data rate ranges from 54 Mbit/s to 600 Mbit/s. The IEEE has approved the amendment, and it was published in October 2009. Prior to the final ratification, enterprises were already migrating to 802.11n networks based on the Wi-Fi Alliance's certification of products conforming to a 2007 draft of the 802.11n proposal.
- 802.11ac - IEEE 802.11ac-2013 is an amendment to IEEE 802.11, published in December 2013, that builds on 802.11n. Changes compared to 802.11n include wider channels (80 or 160 MHz versus 40 MHz) in the 5 GHz band, more spatial streams (up to eight versus four), higher-order modulation (up to 256-QAM vs. 64-QAM), and the addition of Multi-user MIMO (MU-MIMO). As of October 2013, high-end implementations support 80 MHz channels, three spatial streams, and 256-QAM, yielding a data rate of up to 433.3 Mbit/s per spatial stream, 1300 Mbit/s total, in 80 MHz channels in the 5 GHz band. Vendors have announced plans to release so-called "Wave 2" devices with support for 160 MHz channels, four spatial streams, and MU-MIMO in 2014 and 2015.
- 802.11ad - IEEE 802.11ad is an amendment that defines a new physical layer for 802.11 networks to operate in the 60 GHz millimeter wave spectrum. This frequency band has significantly different propagation characteristics than the 2.4 GHz and 5 GHz bands where Wi-Fi networks operate. Products implementing the 802.11ad standard are being brought to market under the WiGig brand name. The certification program is now being developed by the Wi-Fi Alliance instead of the now defunct WiGig Alliance. The peak transmission rate of 802.11ad is 7 Gbit/s.
Now we'll talk about Hubs and Switches, please note that most routers come with a 3-5 port switch built into them.Hubs & Switches
- A "Network Hub" will allow you to connect multiple systems into your network, it functions much like a switch however a "Network Switch" will actually manage your traffic which goes through it and is thus the recommended medium.Cabling Standards
- There are many types of network cable, all listed as "categories":
- Category 1 - Previously used for telephone and doorbell wiring.
- Category 2 - Previously used for "Token Ring" networks.
- Category 3 - Rated at 16 MHz
- Category 4 - Rated at 20 MHz, Previously used for "Token Ring" networks.
- Category 5 - Does NOT support Gigabit Networks - 100 MHz Rating
- Category 5e - Supports Gigabit Networks (although not recommended) - 100 MHz Rating - 2500 Mbit/s
- Category 6 - Supports Gigabit Networks, Backward Compatable with Cat5 - 250 MHz Rating - 5000 Mbit/s
- Category 6a - Supports 10 Gigabit Applications - 500 MHz Rating - 10000 Mbit/s
- Category 7 - Supports 100 Gigabit Applications - Rated at 600 MHz - 100000 Mbit/s
Since most modern networking equipment support "Automatic Crossover", we won't even go into the different types of crossover cabling that is available. Additionally, fiber optic cable is generally out of the scope of this article.
We recommend Cat6/Cat6a cabling for any wired networking project as Cat7 is outside of the official cabling standards (though, it costs about the same as Cat6a); if your organization doesn't rely on official specifications then Cat7 cables could be worthwhile due to the throughput rating.
You should not use any cabling prior to Cat5e, they're not rated for 10/100 MHz networks and several are not recognized as cabling standards (even Standard Cat5).