jsonschema - "required" keyword in JSON schema -

i got below schema http://json-schema.org/examples.html, want know if required keyword can come @ top level. or can come within properties if there property of type object.i not find thing related in specification http://tools.ietf.org/html/draft-fge-json-schema-validation-00#section-5.4.3.

{     "title": "example schema",     "type": "object",     "properties": {         "firstname": {             "type": "string"         },         "lastname": {             "type": "string"         },         "age": {             "description": "age in years",             "type": "integer",             "minimum": 0         }     },     "required": ["firstname", "lastname"] } 

so below example valid schema

{      "title":"example schema",    "type":"object",    "properties":{         "firstname":{            "type":"string"       },       "lastname":{            "type":"string"       },       "age":{            "type":"object",          "properties":{               "minage":{                  "type":"number"             },             "maxage":{                  "type":"number"             },             "required":[                  "minage",                "maxage"             ]          }       }    },    "required":[         "firstname",       "lastname"    ] } 

4.4 keywords possibility validate container instances (arrays or objects) validate instances , not children (array items or object properties).

so see yes, can have on level validation should consider on same level required