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This category consists of posts which form “1st beta” of the Vol. 2 (Development) of the upcoming 3-volume monster “Development & Deployment of Multiplayer Online Games”. Please note that order of the posts is “as they were published on this site”, and is not exactly the same as the order of the Chapters within Vol. 2. For Chapters in correct order – please refer to ToC of Vol. 2.

D&D of MOGs: Vol.2 (1st beta), page 1:

Packet Loss for an App-Level Developer. Part I. Router Failures, BGP Convergence Time, AQM, Traffic Shapers.

Quote: “All the routers, switches (actually – pretty much each and every device which forms Internet infrastructure) – are allowed to drop each and every packet.”
Another Quote: “TCP, when it observes a dropped packet, interprets it as an indication of congestion – and slows down.”

Indirect and Client-Centric Payment Processing. Logging and Reconciliation

Quote: “Fortunately, there is a neat crypto-trick which makes this schema usable for Server-oriented games in general – and multi-player games in particular”
Another Quote: “if you’re using TCP to communicate, you should log everything right before it goes into your send() call (and right after it comes out of your recv() call”

Direct Payment Processing. Recovery from ‘Unknown’ Transaction Status. PCI DSS.

Quote: “With the Direct Processing, customer should trust us (the merchant) with their details”
Another Quote: “On the other hand, most of PCI DSS requirements make perfect sense regardless of formal compliance”

Payment Processing. Credit Cards. Chargebacks and Collateral Damage

Quote: “Chargeback monster will come from under the bed and will eat all your hard-earned money!”
Another Quote: “it is trivial to develop a system with guaranteed zero chargeback rate – to achieve this, it is sufficient to decline each and every transaction at pre-filter stage”

Gradual OLTP DB Development – from Zero to 10 Billion Transactions per Year and Beyond

Quote: “to make an efficient representation usable for OLAP – we need to modify our data on its way to OLAP replicas”
Another Quote: “Each of the DB Server Apps is a replica master, but all replica targets are within the same Replica DB”

Representing The Same Data Structure in SQL and NoSQL (from Classical Codd-style SQL to Key-Value NoSQL with SQL-with-XML and Structured NoSQL in between)

Quote: “while duplication MAY indeed improve performance – undue duplication also MAY hit performance pretty badly”
Another Quote: “NoSQL will usually call for another denormalisation on top of what we’ve described above for SQL-with-XML.”

OLTP. Compiling SQL Bindings.

Quote: “If we’re speaking about millions transactions per day over just a few hundred of different SQL statements – compiling those statements a million times (instead of a few hundred times) will be a dramatic waste of resources.”
Another Quote: “Once upon a time, I observed the largest C++ file in my career – it was a 30’000-line file(!) consisting merely of ODBC bindings (and that was just for 300 or so SQL statements)”