Amazon Web Service RDS-EC2 interaction

Question

I am pretty new to AWS.

I have an EC2 instance running a Java web app on Tomcat, and I need to connect it to an Oracle RDS instance. The intances are in the same region.

• what are the performance associated with the communication between two instances? Are they the same that I would see if both istances would run in my home LAN?
• what about security of RDS instance? If I open port 1521 in the security group (for allowing access to EC2 instance), then the db instance will be exposed to public network?

Do you think that for such situation would be better a VPC?

Thank you

Answer 1

P1) Make sure EC2 and RDS are in same AZ

P2) Make sure you use bigger instance types for NW bandwidth between them

P3) Add PIOPS to RDS if your app demands performance

Answer 2

I have not made any specific measurements, but the connection speed between RDS and EC2 should be very good. Just make sure that the machines are set up in the same availability zone.

Regarding security, you can also specify that access to your RDS machine should be open for specific EC2 groups, so normally the port won't be open publically.