Before starting to work with Wialon, it is necessary to login. Use the command core/login for this action:

svc=core/login&params={"user":<text>,
		       "password":<text>}

After login session is created, you can execute some requests within it. If server haven't received any requests for 10 minutes the session will be killed.

You can find an example of this request in the sample Login/logout.

{
    "uid":<long>,	/* user ID*/
    "eid":<long>,	/* login operations count of current user */
    "ssid":<text>	/* session ID*/
    "pi":<int>,		/* ping interval */
    "tm":<uint>,	/* current time (UTC) */
    "user": {		
        "nm":<text>,		/* name  */
        "cls":<uint>,		/* ID of superclass "user" */
        "id":<long>,		/* ID */
        "gd":<text>,		/* GUID */
        "prp": {		/* custom properties */
		<text>:<text>,		/* property name: value */
		...				
	},
        "pup": {		/* private and public properties */
		<text>:<text>,		/* property name: value */
		...
	},
        "crt":<uint>,		/* creator ID */
        "bact":<uint>,		/* account ID */
        "fl":<uint>,		/* user flags */
	"usnf":{		/* user notifications */
		<text>:{		/* sequence number of notification */
			"t":<uint>,		/* lifetime (sec) */
			"d":<text>,		/* text of notification */
			"h":<text>,		/* subject */
			"s":<text>		/* sender */
		},
		...
	},
        "smsp":<text>		/* phone numbers of user (comma-separated) */
    },
    "classes": {		/* superclasses available for current user (key - superclass name, value - superclass ID): */
        "avl_hw":<uint>,		/* hardware type */
        "avl_resource":<uint>,		/* resource */
        "avl_retranslator":<uint>,	/* retranslator */
        "avl_unit":<uint>,		/* unit */
        "avl_unit_group":<uint>,	/* unit group */
        "user":<uint>			/* user */
    }
}

User flags are described in the chapter Set user settings flags.