Consider sending a large file from a host to another over a tcp connection that has no loss. A. Suppose tcp uses aimd for its congestion control without slow start. Assuming cwnd increases by 1 mss every time a batch of acks is received and assuming approximately constant round-trip times, how long does it take for cwnd increase from 6 mss to 12 mss (assuming no loss events)? B. What is the average throughout (in terms of mss and rtt) for this connection up through time 6 rtt?
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Database (Data) Tier − At this tier, the database resides along with its query processing languages. We also have the relations that define the data and their constraints at this level.
Application (Middle) Tier − At this tier reside the application server and the programs that access the database. For a user, this application tier presents an abstracted view of the database. End-users are unaware of any existence of the database beyond the application. At the other end, the database tier is not aware of any other user beyond the application tier. Hence, the application layer sits in the middle and acts as a mediator between the end-user and the database.
User (Presentation) Tier − End-users operate on this tier and they know nothing about any existence of the database beyond this layer. At this layer, multiple views of the database can be provided by the application. All views are generated by applications that reside in the application tier.