# ☁️ computing

Hardware , system design and system engineering = 1 PC

1 data center = 20 PC

Cloud = 10 data centers = 200 PCs

https://www.hitechnectar.com/blogs/learn-more-about-computing-environment-and-its-different-types/

Why use cloud ?

Heavy / Big data analytics(web traffic) or computation
Storage/data warehouse 
Maintenance or monitoring
Security
Integration with containers
Scaling applications automatically
Better networks

Ex : AWS , Azure , GCP , Digitalocean , IBM

Tips for optimal cloud :
Use multiple cloud providers
Virtualize interrupts and IO
Use VMs
Billing based on performance cycles
SLA ~ SRS(SDE)
Licensing (bulk or pay per use)

Jboss/glassfish = jsp servers(application server)
Tomcat = http server(appn server)
Nginx , Jetty (web server)
SOAP = XML based protocol
Cloudsim = simulation of cloud
VMware , Xen , Virtual box = Hypervisors
Hadoop = big data
SWT(wrapper) , Swing + applet [GUI]
Hibernate ORM
Mail.api Java
Spring+struts
Jsp + servlets
Xampp/wamp/Mamp (Linux local server)

Cloud networking concepts :
1) Traffic and congestion
2) nw virtualization
3) Routing
4) SDN
5) data center networks and physical infrastructure