Huawei HCIE-Datacom key terms

The backbone area in OSPF. All other areas must connect to it, either directly or through a virtual link, and inter-area routes are exchanged through it.

An Area Border Router has interfaces in at least two OSPF areas, including the backbone. It originates summary LSAs to condense topology between areas.

Link State Advertisements carry OSPF topology data. Common types include Router (1), Network (2), Summary (3), ASBR Summary (4), External (5), and NSSA External (7).

An area that blocks Type 5 external LSAs. Routers inside reach external destinations via a default route advertised by the ABR, reducing LSDB and CPU load.

A Not-So-Stubby Area blocks Type 5 LSAs but allows external routes to be injected as Type 7 LSAs, which the ABR translates to Type 5 at the backbone.

IS-IS hierarchy. Level 1 routers share a single area; Level 2 routers form the backbone. L1/L2 routers leak routes between levels, similar to OSPF ABRs.

The Network Entity Title is an OSI address assigned to an IS-IS router. Its system ID must be unique within the domain and is used to build the topology.

A BGP attribute listing autonomous systems a route has traversed. It is used for loop prevention and path selection, with shorter paths generally preferred.

Optional transitive tags attached to BGP routes. They carry no inherent meaning but let operators apply routing policy such as no-export or custom tags across peers.

A BGP router that reflects routes between IBGP clients, removing the full-mesh IBGP requirement. It uses cluster IDs and originator IDs to prevent loops.

Multiprotocol BGP extends BGP to carry address families beyond IPv4 unicast, such as VPNv4, IPv6, and EVPN, using extended communities and route targets.

An extended BGP community used in VPN routing. It controls which VRFs import or export a route, thereby defining VPN membership across the provider network.

Virtual Routing and Forwarding creates separate routing tables on one device. Interfaces are bound to a VRF, isolating customer or tenant traffic.

A set of labels prepended to a packet. Each label is pushed, swapped, or popped by routers, enabling forwarding decisions based on short fixed-length values rather than IP lookups.

Label Distribution Protocol advertises label bindings between MPLS routers so they agree on which label maps to which prefix, building label-switched paths hop by hop.

A source-routing architecture where the ingress node encodes a path as a list of segment IDs in the packet header, removing per-hop state in the core.

Segment Routing over IPv6 encodes segments as 128-bit IPv6 addresses in a Segment Routing Header, allowing programmable paths without MPLS labels.

Ethernet VPN uses BGP control plane signaling to distribute MAC and IP reachability for Layer 2 and Layer 3 services, commonly over VXLAN or MPLS transport.

Virtual Extensible LAN encapsulates Layer 2 frames in UDP, using a 24-bit VNI to support large numbers of isolated segments across an IP underlay.

A Layer 2 broadcast domain identified by a 12-bit tag. Access ports carry one VLAN untagged; trunk ports carry multiple VLANs with 802.1Q tags.

Spanning Tree Protocol prevents Layer 2 loops by electing a root bridge and blocking redundant ports, producing a loop-free logical topology.

Bundles multiple physical links into one logical interface, increasing bandwidth and redundancy. LACP negotiates bundle membership and detects misconfigurations.

A Layer 2 security feature that inspects DHCP messages, trusts only authorized server ports, and builds a binding table used by IP Source Guard and Dynamic ARP Inspection.

Validates ARP packets against the DHCP snooping binding table, dropping spoofed replies to prevent man-in-the-middle attacks on the local segment.

Identifying traffic by ACL, DSCP, or application signature so it can be marked and queued. Classification is the first step in differentiated treatment.

Scheduling packets into priority, weighted, or low-latency queues so that delay-sensitive traffic is served ahead of bulk traffic during congestion.

Policing drops or remarks excess traffic immediately; shaping buffers it and releases it at the committed rate, smoothing bursts at the cost of added delay.

A framework using IKE for key negotiation and ESP or AH for encryption and integrity, protecting site-to-site or remote-access traffic over untrusted networks.

Internet Key Exchange version 2 negotiates IPsec security associations. It supports NAT traversal, multiple child SAs, and more efficient rekeying than version 1.

Generic Routing Encapsulation wraps packets in an IP header to create point-to-point tunnels. It carries multicast and non-IP traffic but provides no encryption.

Network Address Translation rewrites source or destination IP addresses and ports at a boundary, enabling private addresses to reach public networks or overlapping address spaces to coexist.

Stateless Address Autoconfiguration lets hosts build addresses from a router-advertised prefix plus an interface identifier, without a DHCP server.

Neighbor Discovery Protocol uses ICMPv6 for address resolution, router discovery, and duplicate address detection, replacing ARP functions in IPv6 networks.

DHCP for IPv6 assigns addresses and other parameters. Stateful mode tracks leases; stateless mode supplies options such as DNS while hosts self-configure addresses.

Bidirectional Forwarding Detection provides fast failure detection between two nodes using short periodic control packets, triggering routing reconvergence in milliseconds.

A push-model monitoring approach in which network devices periodically stream structured operational data to a collector, replacing slow interval-based SNMP polling.

NETCONF is a protocol for configuring devices via XML RPC operations; YANG models the data structure. Together they enable model-driven, automated configuration.

A Huawei network management and control platform that provides SDN automation, fabric orchestration, and analytics for campus, WAN, and data center networks.