I have of two bird (bird1 and bird2 ) and two Cisco devices (cisco1 and cisco2). I have decided to confirue OSPF MD5 authentification. Whether are compatible Cisco IOS and BIRD at usage OSPF MD5 of authentification? Config of Cisco devices. interface Vlan550 ip address 10.10.1.3 255.255.255.128 ip ospf authentication ip ospf message-digest-key 1 md5 7 0636092546420B12034347 ip ospf priority 5 Config of bird devices interface "eth1.550" { hello 10; retransmit 5; cost 10; transmit delay 1; dead count 4; wait 40; type broadcast; priority 0; authentication cryptographic; password "Prjcsalfr45"; }; Cisco1 with cisco2 have installed the neighbourhood with each other. Bird1 and bird2 have installed the neighbourhood with each other, but CiscoХ birdХ not. Give examples of configs if exist. Vladislav Grishin