Share
Explore BrainMass

Wide Area Network: ATM, CIR, CBR, VBR, UBR

Assume that your organization has to support the following information flows over the Wide Area Network (WAN):

- 10 standard PCM voice circuits
- 5 data communications streams that are each 64-kbps and are active 20% of the time.
- One 10-Mbps video stream
- E-mail traffic as best effort

[a] Given the leasing of a frame relay service, determine the appropriate committed information rate (CIR) for the service.

[b] Given the leasing of an ATM service, allocate the flow among the constant bit rate (CBR), variable bit rate (VBR) and unspecified bit rate (UBR) services.

Attachments

Solution Preview

[a] A standard PCM voice communication takes 64 kbps, so 10 standard PCM voice circuits will deal with 640 kbps voice data.
Voice and video stream data have real-time requirement, so enough bandwidth should be committed to support these.

If we assume the situation that each of the data communication stream is active exclusive of others, during it's share of 20% activity time, then 64 kbps should be added to above bandwidth commitment.

However it could happen that all these data communication streams are active simultaneously, in that case service should be able to accommodate this burst of 5*64 kbps. However this situation is not expected to be there all the time, so it is ...

Solution Summary

Though the attached 1_WAN_n_1_ATM_questions.doc has two questions, this solution addresses only the question posted in the description.

Please note that the given solution is more of a guidance rather than "the solution".

$2.19