Solutions Guide - Networking Hardware
What networking hardware do you need?
All networks need basic hardware components including, cable, network interface
cards and hubs. More complex networks require additional components including
routers and switches. The following is a listing of these components and the
factors that need to be considered in their selection.
Category 5 UTP Cable
Cable:
There are three basic types of cabling: Coax, Fiber optic and Unshielded Twisted
Pair (UTP).
Coax is widely installed in older networks but is not recommended for new
network installations. Fiber is used for high-speed networks and to connect
networking devices separated by large distances.
UTP is currently the most common and recommended cabling type. UTP is inexpensive,
flexible and can transmit data at high speeds. All new installations should
be installed with Category 5 UTP cabling and components. The cabling and components
should be installed and tested in accordance with the TIA 568-A (Telecommunication
Industry Association) standards. This will insure that your cabling system
will meet the bandwidth requirements of 100Mbps Fast Ethernet as well as tomorrows
faster technologies.
Network interface cards: Every computer needs a Network Interface Card (NIC)
to connect to the network. To select the proper network interface card, determine
the speed, bus type and cable connection required.
Network Interface Card
Speed:
Ethernet NIC’s come in two transmission speeds:10Mbps Ethernet and 100Mbps
Fast Ethernet. You can also purchase dual speed NIC’s which can operate
at both 10Mbps and 100Mbps. An advantage of installing dual speed NICs is
that you won’t need to replace them when you upgrade your network to
Fast Ethernet. If you choose Fast Ethernet, all network components must be
rated for this higher speed including your cabling, hubs, and switches.
Bus type: A Network Interface Card plugs into an empty slot on your computer’s
motherboard. You must determine your existing "Slot" or "Bus" type. Most new
computers have PCI (Peripheral Connect Interface) and ISA (Industry Standard
Architecture) slots.
PCI cards should be chosen over ISA because they can transfer data faster
and can support the higher transmission speeds of Fast Ethernet.
Older computers may have ISA, EISA or MCA slots. For older computers, make
sure you have an ISA slot available because most manufactures no longer support
the other bus types. Laptop computers require a credit card size device called
a PC Card to connect them to the network.
Laptop PC Card
Cable connection:
Network Interface Cards can support three types of cable connections: Unshielded
Twisted Pair (UTP) referred to as 10BaseT, Coax referred to as 10Base2, or
Fiber-Optic referred to as 10BaseFL. The majority of new networks are installed
with 4-pair UTP (10BaseT) cabling which uses a rectangular 8-pin modular connector.
Hubs:
Hubs are the central connection point for all devices on your network. The
following factors should be considered when selecting a hub.
24 port hub Speed:
Hubs come in two transmission speeds:10Mbps Ethernet and 100Mbps Fast Ethernet.
You can also purchase dual speed 10/100Mbps "auto-sensing" hubs which sense
what types of network interface cards are attached to them.
In addition, there are "switched" hubs that have one or more 100Mbps-uplink
ports (usually connected to file servers) with the remaining 10Mbps ports dedicated
to desktop PCs.
Shared versus switched:
A shared 10Mbps Ethernet hub repeats information to all computers on the network.
In a shared 10Mbps Ethernet environment, each computer on the network competes
for the same 10Mbps bandwidth. Switched 10Mbps Ethernet hubs have one or more
100Mbps uplink ports that are attached to file servers. In a switched 10Mbps
Ethernet environment, each computer receives a dedicated 10Mpbs of bandwidth.
The maximum available bandwidth in this switched environment is 100Mbps. Switched
hubs increase the performance of your network by reducing network traffic and
providing dedicated bandwidth to computers on your network.
Quantity of ports:
Hubs typically come in 4, 8, 12, 16, 24 and 48 port models. To determine
the number of ports you need, consider the number of desktop PCs and servers
you currently have and allow for at least three years of growth. Also consider
other devices which may be directly connected to the hub such as printers and
routers.
Port partitioning:
Hubs providing this feature can partition-off (shut down) a specific port
when errors are detected on this port. This prevents a malfunctioning network
interface card or other device from affecting the entire network.
Diagnostics:
All hubs should come with diagnostic LED’s to simplify troubleshooting
of network faults (i.e. active connection, transmit, receive, collision and
fault). Some hubs also come with network utilization meters which provide a
simple way to monitor the amount of traffic on your network.
Stackable Hubs:
A stackable hub has a dedicated high-speed interface allowing it to be connected
in series to other stackable hubs. This allows you to add hubs to your existing
network to accommodate additional users.
Managed versus unmanaged:
Managed or "smart" hubs send diagnostic information across the network to
other computers for monitoring purposes. These hubs can notify administrators
of problems and allow the network to be remotely monitored. Managed hubs are
typically used for large networks or for smaller networks requiring remote
troubleshooting and administration.
Routers:
Routers are intelligent devices that use both hardware and software to connect
two networks together. There are four common applications for routers.
ISDN Router
Internet connection:
Routers are used to connect your network to the Internet so that all users
can send and receive e-mail and browse the web over a single Internet connection.
WAN connection:
Routers are used to connect your network to another network (branch office
or main office) over a wide area network (WAN) link.
Segment large networks:
Routers are used to segment (subnet) larger networks. Segmenting breaks a
network into smaller segments for better performance, manageability and security.
Connect dissimilar networks:
Routers can perform media translation when connecting two different types
of networks together (i.e. Ethernet to Token Ring).
Factors to consider when purchasing a router: Some routers integrate several
networking components into one device including network hubs, ISDN adapters
(Integrated Services Digital Network), CSU/DSUs (Channel Service Unit/Data
Service Unit), etc. Some key features to look for in a router are quantity
and type of LAN/WAN interfaces, security, built-in firewall, protocol support,
management capability, and capacity (in packets-per-second).
Bridges:
A bridge is a device that reduces unnecessary network traffic by dividing
your network into logical segments. Bridges are used when a network has grown
in size to the point where network performance starts to degrade and troubleshooting
becomes difficult. A bridge will examine the destination address (MAC address)
of frames transmitted over the network. If the frame is addressed to a device
on the other side of the bridge, the bridge will transmit the frame. Conversely,
if the frame is addressed to a device on the same side of the bridge, the bridge
will simply ignore the frame. In this fashion, a bridge reduces the amount
of traffic on your network. In todays networks, switches have largely replaced
bridges.
Switches:
Unlike a hub that repeats data to all devices attached to it, a switch only
repeats data to devices that the data is intended for. Switches increase network
performance by segmenting larger networks into smaller networks while still
maintaining a connection between them. Switches also increase network performance
by providing dedicated bandwidth to each device connected to it.
8 10Mbps port switch with 3 100Mbps uplink ports
Factors to consider when purchasing a switch: Switches should be used in both
new and existing networks to accommodate a large number of users. Switches
can be installed in existing networks without having to change any existing
equipment such as cabling, network interface cards, hubs, routers, etc. You
should look for the same features in switches as are found in hubs. Some specific
features to look for are capacity and support for virtual LANs (vLANS allow
you to segment your network using software).
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