You require a data replication solution that will replicate data from one disk array in your main data center to a second disk array in a remote data center. This is a crucial part of your High Availability Disaster Recovery solution. The distances involved require you to implement a WAN . You are looking at ATM as a possible WAN solution. Which of the four main types of ATM service would you select and why?
2:
You have implemented a SAN solution over an OC-3c/ STM -1 ATM link. Your business is utilizing more and more data as the days progress. You forecasted that the data usage over the ATM link will be approximately 85GB per hour . You are concerned about data getting to your destination SAN devices in a timely fashion. In particular, you are looking to improve the WAN link by upgrading the ATM link to an OC-12c/ STM -4 backbone to reduce the propagation delays in the WAN . Are your calculations correct, and will the solution meet your stated objectives?
3:
What is the difference between data consistency and data currency in the context of data replication? Which one is more important to an individual application that needs to be able to access online customer data records regardless of which of the paired disks it uses?
4:
What is the difference between hard and soft zoning in a Fibre Channel SAN ? Which type of zoning would you use if you were experiencing lots of HBA failures in your connected devices?
5:
Devices in a VPN use encryption to secure the communication channel they use. Do they use symmetric or asymmetric cryptography? Explain your answer.
