Computer Networking For Business
Are you looking for File/Printer Sharing and High-Speed Internet Access?
Do you want to be able to share a printer or files with all of the other computers in your business? Do you want high speed Internet connectivity? How about sharing streaming Audio or Video files among computers? If so, then Computer Networking is for you.
At ADI we take the time to explain the different options for cabling and Internet connectivity to help you make the right choice for your business. Call or email today for a free quote or read on for more information.
DATA NETWORK CABLING
Businesses of all sizes have a computer network today. With a computer network, you can share data and printers, digital photos, video, and music with other computers in your business. The network can be based on peer to peer connections using 95/98/2000/XP/Vista/Windows 7 networking, or on a server-based network using a Windows NT/2000/2003/2008 or Linux server, or Network Attached Storage (NAS). Also, with high-speed Internet access becoming commonplace, a computer network makes a lot of sense. By adding a device called a router, all of the computers in the business can get high-speed access to the Internet at speeds from 56k bits/sec to 155 Mbits/sec or more. The most common options for business Internet connections are DSL and Cable Modems for small businesses and fractional T1 (up to 1.5 Mbit/sec), T1 (1.5 Mbit/sec) or DS3 (45Mbit/sec) for larger businesses. The most common networking technology for moving data around your business are Etherent (10 Mbit per second, Fast Ethernet (100 Mbit per second), or Gigabit Ethernet (1000 Mbit or 1 Gigabit per second). These technologies run over 4 pair cabling as follows:
Category 3 cabling - Ethernet
Category 5 cabling - Ethernet, Fast Ethernet, or Gig Ethernet (with some limitations)
Category 5E cabling - Ethernet, Fast Ethernet or Gig Ethernet
Category 6 cabling - Same as Category 5e but made to a higher standard
Category 7 cabling - Same as Category 6 but made to a higher standard. This cable is shielded and will have a different connector (not a standard yet)
ETHERNET, FAST ETHERNET AND GIGABIT ETHERNET
No matter what technology you choose for connecting to the Internet, or what operating system you choose for your network, you will want to run Ethernet between your computers. Ethernet has been around since the mid-eighties, and is by far the most popular option. Ethernet runs at 10 Mbits/second, and will run over Cat 3 or above cabling. Ethernet's big brother, Fast Ethernet, runs at 100 Mbits/second, and will run over Cat 5 or above cabling. Cat 5E fixes a near end cross-talk problem that is in some Cat 5 cables, and is preferred for Gigabit Ethernet. In reality, Fast Ethernet is more than enough for most business networks but since most products today support Gigabit Ethernet, you might as well use it. Most business class computers have an Ethernet adapter as a standard option which uses an RJ-45 connector and will allow you to connect it to the Ethernet network. You will need a device called a switch to connect multiple devices together. Ethernet is an IEEE standard (802.3), and the standard calls out a 4 pair (8-wire) cable. In reality, Ethernet only uses 2 pairs of wires, one for transmit and one for receive (Gig Ethernet uses all 4 pairs). At ADI, we recommend running a Category 6, 4-pair cable, home run to your data center. We usually run a Cat 6 cable for network to all locations that have a phone.
A switch is a device that inter-connects all of the PCs, servers and printers together so that they can communicate with each other. There are many options available here, but the main options are speed and managed or non-managed. Most low end switches will support 10/100 Mbit with more expensive ones supporting 10/100/1000 Mbit. Most low end switches are non-managed which means that you really have no way to look into the switch and see what is going on when things go wrong. Managed switches usually have a web interface so you can connect to the switch and configure it and also troubleshoot the network when things do go wrong. Switches can be purchased with 4, 5, 8, 16, 24 or more ports. High end switches are expandable so you can add more ports as your network grows.
In addition to running Cat 6 cabling all over your building, you could choose to add wireless. There are wireless options that run at 11 Mbit/sec (802.11b) and 108 Mbit/second (802.11g) that are cheap and easy to install, or you could choose some of the newer 600 Mbit/sec (802.11n) wireless technologies. Either way, you will buy an Access Point that will connect into your network, and a wireless Network Interface Card (NIC) for each PC that will be connected to the network. Most laptops and many descktop computers are being sold with a wireless NIC built-in as a standard option. When using a wireless network, security is an important consideration. There are easily available tools on the Internet that allow you to snoop the airwaves and look for wireless access points. If you just buy a wireless access point and install it in a default configuration, ANYONE will be able to connect to your network and possibly hack into your computer systems. Here are some of the terms you will see in your access point:
Service Set identifier (SSID)--This is the name of your network and should be changed from the default. With easily available tools found on the Internet, you can sniff this name and if it is the only security you are using, it is not effective at all. Let’s say you buy a Linksys access point and leave the SSID at the default, and someone in a neighboring business buys a Linksys wireless NIC card. Since they have the same defaults, he will be able to connect to your network. If you change the SSID, it at least makes it slightly harder. Keep in mind you have to change it on both the access point and all wireless network cards in your business.
Wired Equivalent Privacy (WEP)--WEP is an encryption algorithm whereby you setup an encryption key on both the access point and the wireless network cards. As data is transmitted it is encrypted (scrambled) and then decrypted (unscrambled) as it is received at the other end. WEP does have a flaw, and there is a tool available on the Internet that can be used to crack the WEP key. But the hacker has to capture around 1 million packets to determine the WEP key, so it takes some time. It is not nearly as easy as finding the SSID, but is doable. Using WEP will not be enough security in most networks.
Wireless Protected Access (WPA) v2--WPA v2 is newer standard that still uses WEP, but it dynamically changes the key every so often. The idea is that by the time a hacker has hacked the WEP key, it is no longer valid. You should always use WPA if it is available. Some older network cards and Access Points do not support WPA. Check the manufacturers web site and there may be a firmware update you can download to enable WPA v2.
Network Attached Storage (NAS)
Instead of using a Windows or Linux server, a NAS is a great choice. In a small network, the server is usually only used as a print server and as centralized storage. Today's NAS products from Netgear, Western Digital, Lacie and others can act as a print server and have lots of storage and are much cheaper and easier to maintain than a server. Usually they will have RAID which guards against data loss. With RAID, if a single hard disk fails no data is lost! They are available in sizes from a few Gigabytes to 10 Tyrabytes or more.
If you have a connection to the Internet, you MUST use a firewall. A Firewall is a device that allows connections out to the Internet, but does not allow people to connect in to your network from the Internet. There are many options here, but Cisco, Checkpoint and Juniper are popular firewall options in large companies with Linksys, D-Link and Netgear being the most popular for small business use. You can buy models that have a 4 or 8 or 16 port switch, a wireless access point, and a firewall all in the same product on the low end. Or you can buy just a stand alone firewall and connect it in to your switched network.
DSL (Digital Subscriber Line) is a technology that can piggy back high speed data services on to one of your existing phone lines. There are many types of DSL, all with different speed capabilities, and all incompatible with each other. The speed that you get depends on how far away you are from the Telephone Company, and how much money you want to spend. Speeds can be up to 20 Mb/second and may be asymmetrical (different speed in-bound than out-bound). Ask your Telephone Company if DSL is an option in your area, and what speeds are available. You get a DSL modem as part of the service, which has an incoming phone line connection, a phone output, and an Ethernet connection.
Other Telephone Company Options
For medium and large sized businesses, your Telephone Company will have options from fractional T1 (56k to 1.5 Mb) to T1 (1.5 Mbit/sec) to fractional DS3 (1.5 Mb to 45 Mb) to DS3 (45 Mb) to OC3 (155 Mb) or larger. Call your Telephone Company to find out pricing.
Cable modems connect to the cable TV system, and give you a high-speed connection to the Internet. If it is available in your area, you will get a cable modem that connects to the cable TV system, and has an Ethernet connection for connecting to the computers in your business. The speed can vary, but is usually in the 5 to 20 Mbits/second range. Most cable systems have been engineered or re-engineered to be bi-directional, but typically the speed you get from your cable modem will be asymmetrical. It will be faster for downloads than for uploads. Also, Cable TV providers are now offering telephone services bundled together with high speed Internet access. Ask your Cable TV operator for details. Cable is typically used in small or medium sized businesses.
Cellular companies like Verizon, AT&T (Cingular) and Sprint have a service that allows you to connect to the Internet by putting a card in to your laptop. But companies like Kyocera and D-Link make routers that will allow you to plug that card in to them. So as long as you are in Cellular range, you can use one of these routers and service to get Internet connectivity. Speeds can be from 1 Mbit/sec up to 20 Mbit/sec for 4G service. This is a great option for small businesses in remote areas where no other option is available, or for temporary networks like at a customer's site or a trade show.