What "single sign" table is used and why is this list of columns needed?

Question

I looked at the diagram and tried to figure out what this table can be used for:

CREATE TABLE "single_sign_ons" 
"token" VARCHAR(64) NOT NULL, 
"ip" VARCHAR(32) NOT NULL, 
"expired_at" DATETIME NOT NULL, 
"one_time" VARCHAR(64), 
"created_at" DATETIME, 
"updated_at" DATETIME, 
"user_id" INTEGER, 
PRIMARY KEY("token"));

What is the "single character" and why does the author of this table include these columns for this purpose?

Answer 1

This is a holder for logging in to the user I believe that the table will be used when the user logs in to verify that their session is still active and to allow them access to various servers / sites without registering a second time.

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Answer 2

Single Sign On - -. , , , . . , Kerberos .

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Answer 3

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Answer 4

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wikipedia :

http://en.wikipedia.org/wiki/Single_sign-on

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