What is a topology?
The physical topology of a network refers to the configuration of
cables, computers, and other peripherals. Physical topology
should not be confused with logical topology which is the method
used to pass information between workstations. Protocol
Point-to-point
The simplest topology is a permanent link between two endpoints.
Switched point-to-point topologies are the basic model of
conventional telephony. The value of a permanent point-to-point
network is the value of guaranteed, or nearly so, communications
between the two endpoints, and in this topology one device send
and only one will received ex: leased lines, ISDN, analog dial-up.
Bus topology
Bus networks (not to be confused with the system bus of a
computer) use a common backbone to connect all devices.
A device wanting to communicate with another device on the
network sends a broadcast message onto the wire that all other
devices see, but only the intended recipient actually accepts and
processes the message ex: Ethernet 10 base 5, 10 base 2
10 base T.
Advantages of a linear bus topology
Easy to connect a computer or peripheral to a linear bus.
Requires less cable length than a star topology.
Disadvantages of a linear bus topology
Entire network shuts down if there is a break in the main cable.
Terminators are required at both ends of the backbone cable.
Difficult to identify the problem if the entire network shuts down.
Not meant to be used as a stand-alone solution in a large building.
Ring topology:
In a ring network, every device has exactly two neighbors for
communication purposes. All messages travel through a ring in the
same direction (either "clockwise" or "counterclockwise"). A failure
in any cable or device breaks the loop and can take down the
entire network. Ring topologies are found in some office buildings
or school campuses ex: FDDI (Fiber Distributed Data Interface).
Star topology:
A star topology is designed with each node (file server,
workstations, and peripherals) connected directly to a central
network. hub or concentrator
Data on a star network passes through the hub or concentrator
before continuing to its destination. The hub or concentrator
manages and controls all functions of the network. It also acts as a
repeater for the data flow. This configuration is common with
twisted pair cable; however, it can also be used with coaxial cable
or fiber optic cable Many home networks use the star topology. A
star network features a central connection point called a "hub" that
may be a hub, switch or router Devices typically connect to the hub
with Unshielded Twisted Pair (UTP) Ethernet.
Mesh topology:
A mesh network in which every device connects to every other is
called a full mesh. As shown in the illustration below, partial mesh
networks also exist in which some devices connect only indirectly
to others there's a redundancy due to Multi backups ex: ATM, FR
it's a communication technique between far devices and Ethernet
The physical topology of a network refers to the configuration of
cables, computers, and other peripherals. Physical topology
should not be confused with logical topology which is the method
used to pass information between workstations. Protocol
Point-to-point
The simplest topology is a permanent link between two endpoints.
Switched point-to-point topologies are the basic model of
conventional telephony. The value of a permanent point-to-point
network is the value of guaranteed, or nearly so, communications
between the two endpoints, and in this topology one device send
and only one will received ex: leased lines, ISDN, analog dial-up.
Bus topology
Bus networks (not to be confused with the system bus of a
computer) use a common backbone to connect all devices.
A device wanting to communicate with another device on the
network sends a broadcast message onto the wire that all other
devices see, but only the intended recipient actually accepts and
processes the message ex: Ethernet 10 base 5, 10 base 2
10 base T.
Advantages of a linear bus topology
Easy to connect a computer or peripheral to a linear bus.
Requires less cable length than a star topology.
Disadvantages of a linear bus topology
Entire network shuts down if there is a break in the main cable.
Terminators are required at both ends of the backbone cable.
Difficult to identify the problem if the entire network shuts down.
Not meant to be used as a stand-alone solution in a large building.
Ring topology:
In a ring network, every device has exactly two neighbors for
communication purposes. All messages travel through a ring in the
same direction (either "clockwise" or "counterclockwise"). A failure
in any cable or device breaks the loop and can take down the
entire network. Ring topologies are found in some office buildings
or school campuses ex: FDDI (Fiber Distributed Data Interface).
Star topology:
A star topology is designed with each node (file server,
workstations, and peripherals) connected directly to a central
network. hub or concentrator
Data on a star network passes through the hub or concentrator
before continuing to its destination. The hub or concentrator
manages and controls all functions of the network. It also acts as a
repeater for the data flow. This configuration is common with
twisted pair cable; however, it can also be used with coaxial cable
or fiber optic cable Many home networks use the star topology. A
star network features a central connection point called a "hub" that
may be a hub, switch or router Devices typically connect to the hub
with Unshielded Twisted Pair (UTP) Ethernet.
Mesh topology:
A mesh network in which every device connects to every other is
called a full mesh. As shown in the illustration below, partial mesh
networks also exist in which some devices connect only indirectly
to others there's a redundancy due to Multi backups ex: ATM, FR
it's a communication technique between far devices and Ethernet
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