How to correctly specify key[] in zabbix when receiving SNMP trap?

Question

Monitoring

I am engaged in setting up monitoring of a satellite receiver 2WCOM DSR01. Zabbix accepts traps from the listener of the following form:

SNMP trap

16:57:37 2017/08/08 PDU INFO:
notificationtype TRAP
transactionid 2064
messageid 0
version 1
errorstatus 0
community Public
errorindex 0
receivedfrom UDP: [192.168.18.49]:41861->[192.168.18.177]:162
requestid 7776
VARBINDS:
iso.3.6.1.2.1.1.3.0 type=67 value=Timeticks: (131065843) 15 days, 4:04:18.43
iso.3.6.1.6.3.1.1.4.1.0 type=6 value=OID: iso.3.6.1.4.1.21529.3.2.1.0.1
iso.3.6.1.2.1.1.1.0 type=4 value=STRING: "DSR01 Basic"
iso.3.6.1.2.1.1.5.0 type=4 value=STRING: "2wcom DSR01"
iso.3.6.1.2.1.1.6.0 type=4 value=STRING: ""
iso.3.6.1.4.1.21529.11.1.2.0 type=4 value=Hex-STRING: 07 E1 08 08 10 39 25 00
iso.3.6.1.4.1.21529.11.1.3.0 type=2 value=INTEGER: 1
iso.3.6.1.4.1.21529.11.1.4.0 type=2 value=INTEGER: 1942
iso.3.6.1.4.1.21529.3.2.1.4.1.3.0 type=2 value=INTEGER: -9900
iso.3.6.1.4.1.21529.3.2.1.4.5.1.0 type=2 value=INTEGER: 1

In this case, only the value is of interest:

iso.3.6.1.4.1.21529.3.2.1.4.1.3.0 type=2 value=INTEGER: -9900

But if you create an Item with the key key[3.6.1.4.1.21529.3.2.1.4.1.3.0], then zabbix still does not parse the message and accepts it as is:

SNMP trap

16:57:37 2017/08/08 PDU INFO:
notificationtype TRAP
transactionid 2064
messageid 0
version 1
errorstatus 0
community Public
errorindex 0
receivedfrom UDP: [192.168.18.49]:41861->[192.168.18.177]:162
requestid 7776
VARBINDS:
iso.3.6.1.2.1.1.3.0 type=67 value=Timeticks: (131065843) 15 days, 4:04:18.43
iso.3.6.1.6.3.1.1.4.1.0 type=6 value=OID: iso.3.6.1.4.1.21529.3.2.1.0.1
iso.3.6.1.2.1.1.1.0 type=4 value=STRING: "DSR01 Basic"
iso.3.6.1.2.1.1.5.0 type=4 value=STRING: "2wcom DSR01"
iso.3.6.1.2.1.1.6.0 type=4 value=STRING: ""
iso.3.6.1.4.1.21529.11.1.2.0 type=4 value=Hex-STRING: 07 E1 08 08 10 39 25 00
iso.3.6.1.4.1.21529.11.1.3.0 type=2 value=INTEGER: 1
iso.3.6.1.4.1.21529.11.1.4.0 type=2 value=INTEGER: 1942
iso.3.6.1.4.1.21529.3.2.1.4.1.3.0 type=2 value=INTEGER: -9900
iso.3.6.1.4.1.21529.3.2.1.4.5.1.0 type=2 value=INTEGER: 1

Or traps will be transferred to Item in this form if there is a line in trap:

iso.3.6.1.4.1.21529.3.2.1.4.1.3.0 type=2 value=INTEGER: -9900

?