Aruba Doc

Is IT a commodity? For Critical, Infrastructure Technology, Advantages Short-Lived – Against High Spending, Differentiation based on use of technology, Level of Innovation not indicative of mature industry How IT transformed industries? 1) Demand driven production, 2) More efficient processes (less inventory, lower cycle times, lower overhead costs, lower prices), 3) Direct Models (Apple, cut-out distributor), 4) Value Networks (Increased outsourcing of activities, Commoditization of industry).

Communication Carriers: Carrier,Analog/Digital, Charge, Data Rate 1) POTS ,A –Switched, Time, modem 2) Leased Analog, A –Leased, Fixed, modem, 3) T series, D –Leased, Fixed, 1.5 - 48 Mbps 4) SONET, D –Leased, Fixed, 51Mbps-2.5Gbps 5) X.25, D –Packet, Usage, negotiable-low 6) Frame Relay, D –Packet, Usage, negotiable-high,

7) ATM, D –Packet, Usage, negotiable-high, 8) MPLS, D –Packet, Usage, negotiable - high

Circuit switching, a channel is reserved from end-to-end for the communicating devices for the duration of the transmission. This channel is available to you for the duration of the call whether you use it or not. Hence, you are charged based on the duration of the call (switched service) or a monthly fee (leased service) and not based on what you send through the channel. Packet switching, all transmission is broken into small packets, each with a source and destination address. Each packet is routed through the network and may take different paths. Packets are assembled on the other side to form the message. There is no channel reserved through the network and charges are based on packets transmitted. Packet switching provides better utilization of resources as there are no reservations, but may degrade quality of service since high traffic levels in the network may increase the amount of time it takes a packet to reach its destination. As we will see shortly, packet switching introduces significant overhead and recent improvements are geared towards...