CS601 GDB Solution Feb 2015

“VidzAudios.com” is a large online streaming company operating in America, this company has implemented packet switching for media streaming, keeping in view the importance of packet buffers; packet switches with various sizes of packet buffers are already installed in company’s network. For Media streaming, network administrator has assured to use efficient queue management algorithms to schedule packets accurately in accurate queue according to its destination.

This company now wants to launch a new voice call service through packet switching, and developed a new network scheduler for this purpose, but this scheduler is causing bufferbloat because of which the network becomes practically unusable for voice calls”.

1. How packet buffers can be beneficial for “VidzAudios.com”, give any two advantages.

it could reduce their complexity, making them easier to build and easier to scale. A typical router linecard today contains about one million packet buffers, using many external DRAM chips. The board space the DRAMs occupy, the pins they require, and the power they dissipate all limit the capacity of the router. By Reducing the buffer size to tens of thousands of pacets, then packet buffers could be incorporated inside the network processor (or ASIC) in a small on-chip SRAM. Not only would external memories be removed, but it would allow the use of fast on-chip SRAM, which scales in speed much faster than DRAM.
2. What could be the possible reason of bufferbloat in above scenario?

Overly large buffers have been placed in some models of equipment by their manufacturers. In this equipment bufferbloat occurs when a network link becomes congested, causing packets to become queued for too long in those buffers. In a first-in first-out queuing system, overly large buffers result in longer queues and higher latency, but do not improve network throughput and may even reduce goodput to zero in extreme cases.