18-03-2011, 06:38 PM
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 | M.Arsalan Qureshi | | Join Date: Oct 2008 Location: Garden Town, Multan Cantt
Posts: 616
Program / Discipline: BSTS Class Roll Number: 09-31 | |
 Process-to-Process Delivery: UDP, TCP, and SCTP
Process-to-Process Delivery: UDP, TCP, and SCTP
* The average data rate, peak data rate, maximum burst size, and effective band-width are qualitative values that describe a data flow. * A data flow can have a constant bit rate, a variable bit rate, or traffic that is bursty. * Congestion control refers to the mechanisms and techniques to control congestion and keep the load below capacity. * Delay and throughput measure the performance of a network. * Open-loop congestion control prevents congestion; closed-loop congestion control removes congestion. * TCP avoids congestion through the use of two strategies: the combination of slow start and additive increase, and multiplicative decrease. * Frame relay avoids congestion through the use of two strategies: backward explicit congestion notification (BECN) and the forward explicit congestion notification (FECN). * A flow can be characterized by its reliability, delay, jitter, and bandwidth. * Scheduling, traffic shaping, resource reservation, and admission control are techniques to improve quality of service (QoS). * FIFO queuing, priority queuing, and weighted fair queuing are scheduling techniques. * Leaky bucket and token bucket are traffic shaping techniques. * Integrated Services is a flow-based QoS model designed for IP. * The Resource Reservation Protocol (RSVP) is a signaling protocol that helps IP create a flow and makes a resource reservation. * Differential Services is a class-based QoS model designed for IP. * Access rate, committed burst size, committed information rate, and excess burst size are attributes to control traffic in Frame Relay. * Quality of service in ATM is based on service classes, user-related attributes, and network-related attributes.
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