Introduction to HAProxy Stick Tables

HTTP requests are stateless by design. However, this raises some questions regarding how to track user activities, including malicious ones, across requests so that you can collect metrics, block users, and make other decisions based on state. The only way to track user activities between one request and the next is to add a mechanism for storing events and categorizing them by client IP or other key.
Out of the box, HAProxy Enterprise Edition and HAProxy give you a fast, in-memory storage called stick tables. Originally, stick tables were created to solve the problem of server persistence. However, StackExchange, the network of Q&A communities that includes Stack Overflow, saw the potential to use them for rate limiting of abusive clients, aid in bot protection, and tracking data transferred on a per client basis. They sponsored further development of stick tables to expand the functionality. Today, stick tables are an incredibly powerful

Original URL:

Original article

The Private Blockchain Fallacy

In all the blockchain hype, a simple, yet self-refuting idea
keeps popping up: a Private Blockchain.

In order to understand why a private blockchain is nonsense, we must
first define what a block chain is and what it is not. Since Nakamoto
coined (PDF) the term, lets see if
his description helps:

a peer-to-peer distributed timestamp server to generate computational
proof of the chronological order of transactions

It does highlight some important traits of “a block chain” (Nakamoto
used a space between both words, I use the current popular term

peer-to-peer: implying distribution; at least ruling out a central
computational proof: implying it to be verifiable
timestamp-server/chronological ordering: it’s goal, but also implying
Marco Iansiti and Karim R Lakhani have a more accessible explanation:

an open, distributed ledger that can record transactions between two
parties efficiently and in a verifiable and permanent way.

open (often called permissionless)
distributed (often called decentralized)
permanent (often called immutable)
In other words: anything that does not match those criteria, is by

Original URL:

Original article

A Cat Meme Photographer from a Century Ago

Much as internet surfers — i.e. everyone in 2018 — enjoy sharing silly and picturesque JPEGs with one another that feature clever quips or inspirational sayings, Americans of a century ago passed around similar memes. They were called postcards, or souvenir cards, and mailing them to friends and relatives was immensely popular for sharing a gilded, snowy holiday scene or even a lolcat.
One hundred years before e-mail inboxes crowded with pictures of cats adorned with text like “I CAN HAS CHEEZBURGER?” and “CEILING CAT IS WATCHING YOU,” lolcats (and loldogs and lolrabbits) were already at the height of fancy. The rise of postcards at the turn of the century enabled Pennsylvanian Harry Whittier Frees to build a career out of photographing cute animals donning hats and britches.
Frees’s work was unique at the time because his shots seemed to display an unlikely cooperation from his furry talent in assuming human poses.

Original URL:

Original article

Proudly powered by WordPress | Theme: Baskerville 2 by Anders Noren.

Up ↑

%d bloggers like this: