System Design, Development, Deploy and Infra

Before looking to cloud migration various factors need to be verified. Few of the are What is the business gain/value for the migration ? What is the organization goals in terms of cloud migration ? Rough estimation of migration cost vs business value What is the status of product life cycle ? Is it in sunset mode ? What are the COTS products used ? What is the license cost changes after migration if any ? Will you able to provide atleast AS-IS functional and non functional requirements of the application. What is the cloud migration strategy that benefit the clients, application and organization ? How to validate AS-IS functionality after migration. How many types of test cases are there ? Is there any need to create new test cases ? (Devils are in details) What is the level of data confidentiality ? What are the readily available cloud features help to reduce the cost of application ? Is user authn and authz are same after migration ? How to migrate users to new platform ? What is th...

  Skip List The skip list is a  probabilisitc data structure  that is built upon the general idea of a  linked list . The skip list uses probability to build subsequent layers of linked lists upon an original linked list. Each additional layer of links contains fewer elements, but no new elements. You can think about the skip list like a subway system. There's one train that stops at every single stop. However, there is also an express train. This train doesn't visit any unique stops, but it will stop at fewer stops. This makes the express train an attractive option if you know where it stops. Skip lists are very useful when you need to be able to concurrently access your data structure. Imagine a  red-black tree , an implementation of the  binary search tree . If you insert a new node into the red-black tree, you might have to rebalance the entire thing, and you won't be able to access your data while this is going on. In a skip list, if you have to insert...

  Consistency Every read receives the most recent write or an error. Availability Every request receives a (non-error) response, without the guarantee that it contains the most recent write. Partition tolerance The system continues to operate despite an arbitrary number of messages being dropped (or delayed) by the network between nodes. When a  network partition  failure happens, it must be decided whether to do one of the following: cancel the operation and thus decrease the availability but ensure consistency proceed with the operation and thus provide availability but risk inconsistency. CAP Theorem Euler Diagram Thus, if there is a network partition, one has to choose between consistency or availability. Note that consistency as defined in the CAP theorem is quite different from the consistency guaranteed in  ACID   database transactions . [4] Linearizability  or strict consistency :  Linear consistency to execute the operations are executed ...

  Protocol Buffers (protobuf) and JSON (JavaScript Object Notation) are both data interchange formats, but they have some key differences in terms of usage, efficiency, and features. Here are some points of comparison: Serialization Format: JSON: It's a human-readable, text-based format. It's easy to read and write for both humans and machines. Protobuf: It's a binary serialization format. While it's not human-readable, it's more compact and efficient for data interchange. Data Types: JSON: Supports a limited set of basic data types, including objects, arrays, strings, numbers, booleans, and null. Protobuf: Supports a broader range of data types, including scalar types (integers, floats, booleans, strings), maps, nested structures, and more. Schema: JSON: Schema is not explicitly defined, which means there is flexibility but less strict validation. Protobuf: Requires a predefined schema (defined in a .proto file). This schema provides a contract for the data s...