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Glite Dictionary
💻 A network flag 🔤 An abbreviation ➕ A prefix meaning with
syn

syn

1 9.9
A flag in a TCP packet used to start a connection between computers
  • noun
  • /sɪn/
  • Specialized
translation icon : SYN
  • After the client transmits the SYN request, it waits for the server to respond with a SYN-ACK packet.

Examples

  • During the connection process, the client sends a SYN packet to initiate communication with the server.

  • The server is going to respond with a second packet, a SYN ACK.

  • I just get a black screen, though our firewall shows a SYN-ACK.

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  • Running Wireshark on the edge server, I see the connection coming in from the ocstest website, but it does not get past the (SYN).

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  • Check the presentation in Module 10 - Session Hijacking; here the TCP/IP 3 Way Handshake is defined as: SYN->

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  • The protocol specifies that a SYN flag is essential for establishing a TCP connection between two devices.

Surface Forms

syn singular
syns plural

Etymology

Syn in computer networks comes from the word synchronize, which means 'to make things start at the same time'. A SYN packet is the 'let's start together' signal used to open a connection, so it marks the start of communication.