Pastebin

basic feature
* test or code can share
* can public, private,... (if login)
* such QR code is easy to read
* need preview for message app, that is, metadata

* UX
  * login user have longer retation of content
  * non login content will loss shorter time
    * they have time to test use this product

TA:
* non-coder, easy of use
* simple for mobile user
* quick note sharing link
* number: MAU will 10,000~50,000, scaling up
  * 1 million when mature

qps:
* DAU: 20% ratio
* 5 post per day
* 1,000,000 * 20% * 5 / 100,000 = 10 qps
* 3~6 month
* limit 1000 char for each note

volume requirement 
* 1,000,000 * 5* 6 * 1kB = 30GB 


read/write ratio: 200: 1
Actor
LB
Actor
Login
not login
Auth,
RateLimit
Backend
NoSQL
DB
SQL
Blob
Storage
Blob
Storage
User_id
xxxx
yyy
aaa
Content
Item 1
Item 2
Item 3
not login
public
login
public, private
RO
Cache
Write
NoSQL
NoSQL
DB
SQL
DB
SQL
Blob
Storage
Blob
Storage
Replication, Failover
Replication, Failover
Geo-replication