IBM's Token Ring protocol uses a star-wired ring topology. The Token Ring Multi-Station Access Unit (MSAU) is the heart of the Token Ring universe.
Star Topology Advantages
Cable Selection - The star topology permits the use of UTP, STP, coaxial and fiber-optic cabling. This allows for greater diversity and flexibility at setup time. The star topology is backwards compatible with the older cable types so long as the central hub/switch supports it.
Cable Installation - Cabling is straightforward and easy to install particularly when UTP CAT5 or above is used.
Connectivity - With devices, connecting directly to the central hub/switch greater freedom of configuration is possible. Moving a PC to somewhere else in the room or even to another star topology room is simple and speedy.
Reduced Outages - Network disruption and downtime is greatly reduced when connecting or removing devices. Generally, there is no need to power down any device other than the device slated for removal.
Peer-to-Peer - Simplified ad hoc Peer-to-Peer (P2P) networking schemata
Troubleshooting - Easier to use & more streamlined troubleshooting courtesy of the ability to isolate problem devices made possible by the star topology's physical connectivity simplicity
Upgrading - Component replacement, upgrading, the installation of service packs, hot fixes, patches and the addition of new features is a lot easier with a star topology than linear bus and physical ring topologies
LAN Switches - Implementation of a star topology in conjunction with LAN Switches, gives us the ability to fragment collision domains. This offers great improvements in network performance over bus and ring topologies
Routers and Virtual Local Area Networks (VLAN) - Adding routers and Virtual Local Area Networks (VLAN) will also improve network performance as well as providing for greater security control over resource allocation and access.
Star Topology Disadvantages
More Cable - More cable is required to implement a star topology than would be the case for a linear bus topology
Single Point of Failure - If the central hub or switch dies then the entire network will be unable to communicate with each other & externals networks
More Expensive - Hubs & switches are not free and additional cable adds to initial outlay costs to the implementation of the star topology in comparison to the linear bus topology
Network Operating System (NOS) Images
As I have been having trouble sending, the graphics with these articles I have decided to include said graphics for the entire series in a separate photo gallery entitled “Network Operating System (NOS) Images”.
I will also keep on trying to send them embedded into each article. Once the upgrade to the lines in our area is complete, things should be better.
Next time in “Network Operating System Ring and Tree Topologies”, we will look into the Ring and Tree Topologies including their implementation indicators. Until then enjoy!
