Glossary The All OSPF Routers multicast IP address, listened for by all OSPF routers. The All OSPF DR Routers multicast IP address, listened for by DR and BDR routers.

2Way (OSPF) A neighbor state that signifies the other router has reached neighbor status, having passed the parameter check.

6to4 An IPv6/IPv4 tunneling method.

ABR See area border router.

access layer A Cisco network design term that refers to the devices that connect directly to the user. For LAN designs, the access layer consists of the switches connected to end user hosts. For WANs, the access layer consists mainly of routers at remote sites.

Ack (EIGRP) An EIGRP message that is used to acknowledge reliable EIGRP messages, namely Update, Query, and Reply ...

Get CCNP ROUTE 642-902 Official Certification Guide now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.