1 Overview
1.1 This section shows you:
- The cabling needed to connect the components of your network.
- The difference between twisted pair and coaxial cabling.
- How to connect a coaxial network to a twisted pair network.
2 Twisted pair or coaxial cabling?
2.1 Twisted pair cables and coaxial cables are different types of cable that can be used to connect the equipment when creating a network. Twisted pair cable is easier to use.
2.2 Coaxial cabling was used in Ethernet networks before twisted pair cabling. Coaxial cabling cannot be used in Fast Ethernet networks.
A coaxial network is created by joining sections of coaxial cable with T-pieces, or Y-pieces, to form a long segment. The two free ends of the segment are terminated using end-pieces. PCs are connected to the T-pieces or Y-pieces so that network information, sent along the segment, reaches all the devices.
2.3 The whole coaxial segment must remain intact for the network to operate. This means that if a section of cable is damaged or disconnected, the network is broken making it unusable. Also, making changes to the network, such as adding new PCs, breaks the segment. This makes the network unusable while these changes take place over a period known as 'network down-time'.
2.4 Twisted pair cabling is replacing coaxial cabling. It is more commonly used because it is easier to use and more flexible than coaxial cable. As a result, the majority of Ethernet network equipment today has ports for twisted pair cabling.
A small, twisted pair network is typically created by connecting a hub, or switch, directly to PCs using twisted pair cabling. The hub or switch distributes the network information to the PCs.
2.5 Twisted pair cable has easy-to-use connectors that simply slot into the ports on the devices and network equipment.
If one of the twisted pair cables is damaged or disconnected, only that specific connection is broken and the rest of the network remains operational. Making changes to the network, such as adding PCs, is easy and can be done without affecting other devices on the network.
For Ethernet networks, you can use either Category 3 or Category 5 cable. However, if Category 5 cable is used, you can upgrade your network from Ethernet to Fast Ethernet in the future (as Category 3 cable cannot be used for Fast Ethernet networks).
3 Connecting an existing coaxial network
3.1 Coaxial cabling is more commonly found in older Ethernet networks. To provide a migration path to twisted pair cabling use one of the following OfficeConnect hubs:
If you have 10BASE5 thick coaxial cabling, use the Ethernet Hub 4C and an appropriate transceiver. Contact your supplier for more information about transceivers.
3.2 Connecting the hub to a coaxial network is simple. All you have to do is make the appropriate connection from the existing network to the coaxial port on the hub.
As well as providing a direct coaxial connection to an existing coaxial network, the hubs provide twisted pair ports for flexible connection to the new equipment and other OfficeConnect units. See the Installing a Device installation section on this CD.
When adding hubs to the network, check Ethernet and Fast Ethernet rules in the Network Rules subsection of this CD.
4 Connecting to a WAN
4.1 You can connect to your WAN with an OfficeConnect LAN Modem using either an ISDN or analog connection (check with your supplier for which cable to use).
There are typically three types of telephone cable:
RJ-11/RJ-11 cable is used for analog POTS (plain old telephone system) connections. Use this cable if you have 3Com's OfficeConnect 56K LAN Modem.
RJ-45/RJ-11 is used in North America and other countries that do not require an external NT-1 device. Use this cable if you have the U version of 3Com's OfficeConnect ISDN LAN Modem.
RJ-45/RJ-45 is used in Europe and other countries where an external NT-1 device is required. Use this cable if you have the S/T version of 3Com's OfficeConnect ISDN LAN Modem. Check with your local 3Com reseller for the LAN Modem version available for your geographical area.
