Juniper JN0-664 Exam Dumps - Actual Questions Answers

The customer interface in an LDP-signaled pseudowire is the interface on the PE router that connects to the CE device. An LDP-signaled pseudowire is a type of Layer 2 circuit that uses LDP to establish a point-to-point connection between two PE routers over an MPLS network. The customer interface can have different encapsulation types depending on the type of traffic that is carried over the pseudowire. The encapsulation types are ethernet-ccc, vlan-ccc, extended-vlan-ccc, atm-ccc, frame-relay-ccc, ppp-ccc, cisco-hdlc-ccc, and tcc-ccc. Depending on the encapsulation type, the customer interface can accept or reject tagged or untagged frames in the data plane, and include or exclude VLAN tags in the control plane LDP advertisement. The following table summarizes the behavior of different encapsulation types:

A sham link is a logical link between two PE routers that belong to the same OSPF area but are connected through an L3VPN. A sham link makes the PE routers appear as if they are directly connected, and prevents OSPF from preferring an intra-area back door link over the VPN backbone. To create a sham link, you need to configure the local and remote addresses of the PE routers under the [edit protocols ospf area area-id] hierarchy level1.

BGP FlowSpec is a feature that extends the Border Gateway Protocol (BGP) to enable routers to exchange traffic flow specifications, allowing for more precise control of network traffic. The BGP FlowSpec feature enables routers to advertise and receive information about specific flows in the network, such as those originating from a particular source or destined for a particular destination. Routers can then use this information to construct traffic filters that allow or deny packets of a certain type, rate limit flows, or perform other actions1. BGP FlowSpec can also help in filtering traffic and taking action against distributed denial of service (DDoS) attacks by dropping the DDoS traffic or diverting it to an analyzer2. BGP FlowSpec rules are internally converted to equivalent Cisco Common Classification Policy Language (C3PL) representing corresponding match and action parameters2. Therefore, BGP FlowSpec uses dynamically created routing policies to protect a network from denial-of-service attacks.

References: 1: https://www.networkingsignal.com/what-is-bgp-flowspec/  2: https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/iproute_bgp/configuration/xe-16/irg-xe-16-book/bgp-flowspec-route-reflector-support.html