EP29: On-line Gaming Protocol – by Alex Xu

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A typical apply is to make use of RUDP (Dependable UDP). It provides a dependable mechanism on high of UDP to supply a lot decrease latency than TCP and assure accuracy.

The diagram under reveals how dependable information supply is applied in on-line gaming to get eventually-synchronized states.

Suppose there’s a huge struggle in a simulation shooter sport. Characters A, B, and C open fires in sequence. How does the sport server transmit the states from the sport server to the sport consumer?

• Steps 1 and a pair of – Character A opens fires. The packet (packet 0) is shipped to the consumer. The consumer acknowledges the server.

• Step 3 – Character B opens hearth. The packet is misplaced throughout transmission.

• Steps 4 and 5 – Character C opens hearth. The packet (packet 2) is shipped to the consumer. For the reason that final efficiently delivered packet is packet 0, the consumer is aware of that packet 1 is misplaced, so packet 2 is buffered on the consumer facet. The consumer acknowledges the server for the reception of packet 2.

• Steps 6 and seven – The server doesn’t obtain the ack for packet 1 for some time, so it resends packet 1. When the consumer receives packet 1, all the next packets grow to be efficient, so packets 1 and a pair of grow to be “delivered”. The consumer then acknowledges the server for the reception of packet 1. No packets are buffered at this level.

Let’s first outline what “safe” means. A “safe” chat in a messaging App usually means the message is encrypted on the sender facet and is barely decryptable on the receiver facet. It is usually referred to as “E2EE” (end-to-end encryption).

On this sense, is Telegram safe? It relies upon.

Telegram’s standard non-public and group chats aren’t end-to-end encrypted
It usually means third events can intercept and browse your messages. Telegram makes use of the next method for safety:

• The encrypted message is saved in Telegram servers, however cut up into a number of items and saved in several nations.

• The decryption keys are additionally cut up and saved in several nations.

This implies the hacker must get message chunks and keys from all locations. It’s potential however extraordinarily tough.

Secret chats are end-to-end encrypted
 In the event you select the “secret chat” choice, it’s end-to-end encrypted. It has a number of limitations:

• B-Tree
  B-Tree is probably the most extensively used indexing information construction in virtually all relational databases.

  The essential unit of knowledge storage in B-Tree is often referred to as a “web page”. Wanting up a key traces down the vary of keys till the precise worth is discovered.

  LSM-Tree
  LSM-Tree (Log-Structured Merge Tree) is extensively utilized by many NoSQL databases, reminiscent of Cassandra, LevelDB, and RocksDB. 

  LSM-trees preserve key-value pairs and are continued to disk utilizing a Sorted Strings Desk (SSTable), through which the keys are sorted.

  Degree 0 segments are periodically merged into Degree 1 segments. This course of is named compaction.

  The most important distinction might be this:

• B-Tree allows quicker reads

• LSM-Tree allows quick writes

In the event you use markdown and mindmap, you will most likely like this device.