What are the key design issues of a computer network?

In my view, the key design issues with regards computer network can be considered the following:

1. Security

2. Scalability

3. Availability

4. Manageability, and

5. the quality of the hardware. 

key design issues of a computer Network

a. Connectivity

b. Cost-effective Resource Sharing

c. Support for common Services

d. Performance

have a look at

 https://www.classle.net/submission/key-design-issues-computer-network

• key design issues of a computer Network
• Connectivity
• Cost-effective Resource Sharing
• Support for common Services
• Performance

 1.Data Transfer Rules- The protocol used must determine the number of channels needed and the priorities to be used. This is based on the mode of communication (simplex, half-duplex and full-duplex)

2.The protocol that the layers use must be able to correct the sequence of the packets received if they are not in correct order.

3.Another major issue is the maximum size of data that can be sent and received at one go. This leads to the need for segmentation at the sending end and re assembly at the receiving end.

4.The problem is that if the sending packets are too small in size, then the process becomes inefficient.

 5. A The sender and receiver identification must be made possible for each layers. This can be achieved by some form of addressing.

        B common form of error control and error correction on both the sending and receiving ends.

6. Rate of sending and rate of receiving must    match. If the rate of sending is too high that the receiver cant cope up, it leads to congestion and packet loss. Flow control can be used in these cases.

 7. Choosing the best possible route between the sender and the receiver when more than one path is available for data traversal

Number One design issue of Computer Networks is to ensure full time connectivity, after connectivity the next ranked issue by priority is to ensure cost effective resource sharing, then on next level the important concern is related to give support for common services, and at last but not least, the union set of all issues is the Performance of Network.

planing an design and keep it flexible  

great planning an a design to meet the needs of the business, not the needs of the it team. Keep it flexible and ensure there are as few bottlenecks as possible (future).