A question about MAN,DQDB and SMDS

[kidd]

This is a question from my lecturer,i really cannot answer it because i dun understand about DQDB and SMDS,so wish anyone expert can tell me about it or give me some information for it.It is not much website can be found the information.If u know some website about this,please let me know,i will research it.Thank you all...

The question is:

A metropolitan areal network(MAN) is a network designed to extend over an entire city.Most organizations find that even if they could get permits to lay cables on public land,a better alternative is to use the services of existing utilities,such as Telephone Company.These services include:distributed queue dual bus(DQDB) and switched multimegabit data services(SMDS).Explain how the data transmission in DQDB is done and how SMDS is used for MAN.

Thanks a lot for help me.

 

[russ_watters]

Please don't multi-post.

 

[ravenprp]

Sure, I can provide some information on DQDB and SMDS for you.

Distributed Queue Dual Bus (DQDB) is a network technology used in MANs to provide high-speed data transmission over a shared medium. It uses a dual bus architecture, where two buses are used for data transmission in opposite directions. The data is divided into cells and each cell is given a priority level, which determines its position in the queue. The bus is shared by multiple nodes, and each node has a unique address. When a node wants to transmit data, it first checks if the bus is available. If it is, the node sends its data in the form of cells. If the bus is busy, the node waits until it is available. The cells are transmitted in a round-robin fashion, with higher priority cells being transmitted first. This ensures fair access to the bus and prevents one node from dominating the transmission.

Switched Multimegabit Data Services (SMDS) is a technology used in MANs to provide high-speed data transmission over a switched network. It uses a packet-switching technique, where data is divided into packets and each packet is given a destination address. The packets are then routed through the network to their destination. SMDS uses a connectionless approach, meaning that there is no pre-established connection between the sender and receiver. This allows for more efficient use of network resources and faster transmission speeds. SMDS also supports multiple classes of service, allowing for different levels of data transmission based on priority.

In a MAN, SMDS is used as a backbone network to interconnect different LANs and provide high-speed data transmission between them. It is typically used for data-intensive applications such as video conferencing, file sharing, and real-time data transfer. SMDS provides a cost-effective solution for MANs, as it utilizes existing infrastructure and allows for easy scalability.

I hope this helps to answer your question and provide some clarity on DQDB and SMDS. As for websites, some good resources for further reading on these topics include Cisco's website and IEEE publications. I would also recommend checking out some academic journals and books on networking for more in-depth information. Best of luck in your research!