So finally, near the end of the flight season, the time for my first solo flight in a glider has come.
Got two solo flights in a row thanks to my flight instructor :). And yes, this time nobody was in the backseat anymore.
1. Anycast v/s Multicast v/s Broadcast v/s Unicast
Multicast is like a broadcast that can cross subnets, but unlike broadcast does not touch all
nodes. Nodes have to subscribe to a multicast group to receive information.
To use Anycast you advertise the same network in multiple spots of the Internet, and rely on
shortest-path calculations to funnel clients to your multiple locations. As far the network
nodes themselves are concerned, they’re using a unicast connection to talk to your anycasted nodes. Anycast is announcing the same network in different parts of the network,
in order to decrease the network hops needed to get to that network.
A database shard is a horizontal partition of data in a database or search engine. Each
individual partition is referred to as a shard or database shard. Each shard is held on a
separate database server instance, to spread load.
3. PV v/s HVM
HVM AMIs are presented with a fully virtualized set of hardware and boot by executing the
master boot record of the root block device of your image. This virtualization type provides
the ability to run an operating system directly on top of a virtual machine without any
modification, as if it were run on the bare-metal hardware. The Amazon EC2 host system
emulates some or all of the underlying hardware that is presented to the guest
Paravirtual guests can run on host hardware that does not have explicit support for
virtualization, but they cannot take advantage of special hardware extensions such as
enhanced networking or GPU processing.
For the best performance, we recommend that you use current generation instance types
and HVM AMIs when you launch your instances