Ethernet or Token Ring

Ethernet or Token Ring

Keith Rulli

IT 242

February 12, 2014

Randy Guin

Ethernet or Token Ring

        Saguaro Federal is an organization associated with the federal government, and connected to banks and other businesses.  This organization’s status and size suggests to me that it would be able to fund whatever top of the line system that they decide on.  The use of mainframes suggests that the network moves a massive amount of information and must be able to support very heavy traffic.  If the network design to be implemented pertains to the mainframes and the servers for performance I choose a switched Ethernet network over a token ring.  The network switches reduce congestion more than other network devices would.

        Ethernet is the current standard for LAN’s in the market and less expensive.  Common Ethernet speeds are 10 Mbs/100 Mbps, although there is also 1000 Mbps (1 G), 10G, 40 G, and 100 G.  ("High-Speed Ethernet Planning Guide", 2011).  The NIC’s of the devices must be able to support the Ethernet speed.  Ethernet uses the Carrier Sense Multiple Access/Collision Detection (CSMA/CD) protocol, allowing all devices to transmit frames at any time.  When two or more stations transmit frames simultaneously it causes a collision which is immediately detected.  Then the stations involved in the collision are given a random time interval before they can attempt to transmit again.    

        Speeds of token ring networks are between 4 and 16 Mbps, including the speeds of token ring network cards. ("Token Ring Networks", n.d.).   Advances in token ring technology may now enable speeds up to 100 Mbps.   Bandwidth usage is optimized because collisions between transmissions are eliminated.  The right to transmit data is granted by a token that is passed sequentially around the ring structure.  When a computer has data to transmit, it recieves an empty token and attaches frames that contain data in packets.   The token ring protocol offers larger packet sizes than Ethernet and the faster the speed of the ring the larger the packet size. ("Does Anyone Actually Still Use Token Ring?", 2008). Larger packet sizes result in less packets on the wire or fiber-optic cable, reducing network  congestion which can cause response times to fluctuate.  Computers that the token is not addressed to ignore and pass it until it reaches it’s destination.  A token ring network device called a Multistation Access Unit (MAU), connects computers in a physical star topology while allowing data to move in a logical ring. ("Token Ring Networks", n.d.).