Small businessmen have real challenges when it comes to IT in their business. They all need it and most of them don’t understand it. What makes it worse is the amount of terrible advice they get ranging from recommending they spend far too much money to “saving a packet” and having an unreliable environment that causes losses due to down time. I thought I’d write a few posts about this topic starting with The Network.
The Network is what ties everything together in the office. It’s driven by that pizza-box shaped thing that all the blue cables with the over-sized phone connectors plug into (otherwise known as a switch which has Ethernet cables with RJ-45 connectors plugged into it). The Network is one of the most innocuous and yet vital elements of your environment since if it fails, everything breaks. Because of this, it’s worth investing in a quality device. On the positive side, a quality network switch should last your business 5-7 years. There are a few considerations that need to be taken into account with any switch that you purchase; they are:
- Speed (Throughput)
- Power (Power over Ethernet)
- QoS (Quality of Service)
- Let’s cover each of these
A made a point to a colleague recently that Gigabit Ethernet is a waste of money but I didn’t expand on that point. Most PCs support GbE as do most File Servers. Unfortunately, most IP Phones do not. The Digital PABX is dead; very few vendors still make them and they are starting to cost far more than newer IP PABXs (VoIP) to manufacture and hence buy. One of the benefits of VoIP is being able to “double hop” a cable; i.e. plug the phone into the wall (and back to the switch) and then plug your PC into your phone. The problem here is that the majority of IP Phones only use 100Mbps Ethernet (IP telephony only consumes about 100Kbps) so even if you have Gigabit Ethernet at your switch, you still only get 100 Mbps Ethernet to your desk. The next issue is your File Server since it’s probably plugged into your network at GbE as well-meaning that if you are in an office of – for example – 40 people then you are sharing that GbE at a 1:40 ratio during peak periods of the day (NB: 100Mbps switches usually include a few GbE ports specifically to connect to File Servers (or other switches) specifically so that the Server has more bandwidth than any one user can consume). To fix this issue requires either aggregating multiple GbE links into your Server (generally you can use up to 8 without much difficulty) or investing in 10GbE between your Server and your switch. The problem with the former solution is that is is messy (up to 8 cables) and consumes a lot of network ports. The problem with the latter solution is that it can be fairly expensive. For these reasons, I generally recommend against GbE. The reality is that unless you work with very large files all day (e.g. desktop publishing, architects, etc.) you really won’t notice the difference. This becomes even more relevant if a business starts migrating towards a Cloud Infrastructure – where much (or all) of the data and applications are hosted elsewhere. In this situation, the performance of the network becomes almost completely irrelevant since the limiting factor (i.e. bottleneck) becomes the business’ link to The Internet or Private Network that connects them to the Cloud. Few small businesses today have links of speeds greater than 2-4Mbps (or ADSL but since that only provides high-speed downloads, it is less than ideal for Cloud deployments) although some in heavily urban areas may have up to 10Mbps – still far shy of the 100Mbps network they probably have deployed.
There is one caveat here though which is the relatively new high-speed Wireless network (802.1n) which requires that you run it across Gigabit Ethernet since it allows for connection speeds greater than 100Mbps (up to 600Mbps is allowed for in the design). My general recommendation for most small businesses is thus to deploy 100Mbps to the desktop and Gigabit Ethernet to the File Servers and newer Wireless Access Points.
Power over Ethernet
As per the previous section, virtually all Telephony these days is moving towards VoIP which inevitably leads to a need for Power over Ethernet (PoE) networks to power the phones (unless you want a power brick at each desk). PoE can also provide power for other devices such as Wireless Access Points, IP surveillance cameras, etc. The original standard for PoE was for 48v DC @ 14.4w (12.8 delivered) this is enough for virtually any device short of a a Pan Tilt Zoom camera which needs more power to drive its motors. The more recent standard – PoE+ - can deliver nearly 30w and is frequently all that is on offer these days. Since powering devices via DC over the Network is far more efficient than AC plugs, got with PoE+. NB: Some vendors are promoting even higher power delivery on their switches but these involve proprietary technology and are generally useless since there are few if any devices that current draw that much current. There is a new standard being developed to deliver higher power with the theory that you will be able to charge laptop batteries or power Thin Clients across the Network but until that standard is ratified, stick with the current technology.
Quality of Service (QoS)
In over 10 years of working with VoIP and Unified Communications, the number one issue I have encountered is organisations’ not deployment appropriate QoS for their IP Phones. The argument is always something along the lines of “VoIP only uses 100Kbps and we have a 100Mbps/GbE network; we have loads of capacity, we don’t need QoS! This is completely wrong as the nature of Ethernet Networking is such that – by default – applications which demand most bandwidth (e.g. print jobs or large file copies) get the most bandwidth (see my upcoming article CSMA/CD is a sledgehammer for a more technical overview of why this is so). This means that a single large print job can starve (and that is the technical term) your IP phones of bandwidth and hence cause poor call quality or even dropouts. This is relevant for other light-bandwidth applications as well (things like Telnet in the past and many current cloud applications). It is for this reason that QoS was developed as it allows for time-sensitive traffic to gain priority on the network over bulkier but less sensitive traffic (e.g. a half-second delay in the delivery of an email is irrelevant but a half-second delay in a phone conversation is unacceptable). There are two broad types of QoS; L2 and L3. The technical details of these are beyond the scope of this post but you should ensure your business invests in a switch that supports both L2 and L3 QoS.
This is a bit of a sticky subject. On the one-hand, a network switch is a mostly solid-state device, with the only moving parts being the cooling fans (if any) which makes it a very robust device with a much lower fail-rate than File Server, Printers or Desktops. On the other hand, as mentioned previously, if the Network breaks you might as well send everyone home. Whilst there are fully redundant Network devices available (where they can survive the failure of any single component), these are generally very expensive and are designed for large deployments or data centers. Most Network vendors offer a good compromise through either partially redundant Switches (most often supplied with multiple Power Supplies and modular data ports) or Virtual Chassis (where multiple network switches are “stacked” to act as a single switch, and File Servers can have links to each of them so that if a unit crashes, the File Server and at least part of the network will continue to function. Both approaches are quite solid; a redundant device has a far greater impact if it fails than does a Virtual Chassis but a redundant device is also somewhat less likely to fail. Choose one of these approaches if possible; avoid a single stand-alone device as this will leave the business quite vulnerable to a complete outage.
Maintenance in the IT world means the cost to maintain the warranty and software licensing of a device (rather than physical maintenance of something like an Air Conditioner). It is important that you maintain your device both for security and reliability – so that you can obtain a software patch if a problem is discovered with your switch’s software – and for recovery – so that you can rapidly replace a device that fails. The cost of maintenance can vary wildly from vendor to vendor. May offer “lifetime warranty” with a fine-print caveat that replacement could take up to 10 business days whilst the best offer “lifetime warranty” with Next Business Day replacement. The former offering is useless whilst the latter could still mean a day+ of lost business in the event of a failure. The appropriate maintenance for your Network should be the same as for your File Servers which is generally same day 4 hour response. Make sure that the vendor you buy your switch from offers this level of support and check its price; some vendors will charge you nearly as much (or more) for three years maintenance as the initial cost of the switch (so in its 5-7 year life you are effectively buying it three times).
I hope this helps you with your choice of networking device and I welcome any comments.