In certain networks, for example; Multiprotocol Label Switching (MPLS) Virtual Private Network (VPN) applications rely upon Label Switched Paths (LSP’s) set up by Label Distribution Protocol (LDP), in these networks, it is possible for the IGP to become operational on a link on which LDP is not resulting in labeled traffic being blackholed. IP packets could still … Read more now..
Well-known IPv6 multicast addresses Source address is always unicast Router Advertisement(ICMPv6 type 134): Advertisements are sent periodically, every 200 seconds (cisco). They are also sent immediately as a response to a Router Solicitation message originated by an end host. Router Solicitation(ICMPv6 type 133): Sent upon an interface of a node being enabled (FF02::2). Redirect(ICMPv6 type … Read more now..
Serial interfaces can have different types of encapsulations and each encapsulation type determines the kind of keepalives that will be used. Enter the keepalive command in interface configuration mode in order to set the frequency at which a router sends ECHOREQ packets to its peer, keepalives can also be disabled with the “keepalive 0″ or … Read more now..