Nokia BGP Fundamentals for Services study plan
Nokia BGP Fundamentals for Services · Give each week a clear focus.
8 weeks · About 6 hours per week
BGP Fundamentals and Protocol Operation
Explain from memory the four BGP message types and the finite state machine transitions between Idle, Connect, Active, OpenSent, OpenConfirm, and Established
Describe how NLRI, path attributes, and the AS_PATH are encoded in UPDATE messages, including the role of ORIGIN, NEXT_HOP, and AS_PATH as well-known mandatory attributes
Distinguish iBGP from eBGP behavior on AS_PATH prepending, NEXT_HOP handling, and split-horizon-style loop prevention
Trace a route from origination through advertisement to a peer and identify at each step which attribute changes
Your checkpoint
A one-page hand-drawn or text diagram of the BGP FSM with each state's trigger event and a table listing every well-known and optional attribute with its category and purpose
BGP Path Selection and Best-Path Decision
Rank the standard BGP best-path steps in exact order and state which step breaks ties before the others
Work through five constructed route-comparison scenarios and select the winner, justifying the deciding step each time
Explain why LOCAL_PREF is exchanged only within an AS and how MED differs in scope and default behavior
Describe multipath and deterministic-med behavior and how each alters naive best-path reasoning
Your checkpoint
A scored set of five best-path scenarios with written justifications, plus a personal mnemonic sheet of the selection order that you can reproduce from memory
Route Advertisement, Filtering, and Policy
Build prefix lists, AS-path filters, and route maps that implement a stated peering policy for a customer, a peer, and a transit provider
Explain the difference between inbound and outbound filtering and predict the effect of each on advertised versus received routes
Configure and interpret a maximum-prefix limit with a warning and restart threshold, and describe what happens on violation
Describe communities (standard and large) and use one to tag and act on a route at a downstream router
Your checkpoint
A policy design document for a three-peer topology: for each neighbor, the inbound and outbound filters, the communities applied, and the expected RIB-in and RIB-out contents
BGP Sessions, Peering Types, and Transport
Compare eBGP multihop, loopback-based peering, and directly connected peering, and state when each is appropriate
Explain TTL security and its interaction with multihop peering
Describe authentication, TCP MD5, and TCP-AO at a conceptual level and their operational trade-offs
Diagnose a session stuck in Active or OpenSent given only a symptom description
Your checkpoint
A troubleshooting decision tree mapping session states and symptoms to likely causes and verification commands, validated against at least three invented failure scenarios
Scaling: Route Reflectors, Confederations, and Peer Groups
Explain why full-mesh iBGP does not scale and how a route reflector removes the requirement, including the roles of client and non-client
Describe cluster ID and ORIGINATOR_ID loop prevention and predict behavior with redundant reflectors
Compare route reflectors with confederations on configuration complexity, policy visibility, and AS_PATH effects
Design peer groups and session templates that reduce configuration repetition for a 20-neighbor edge
Your checkpoint
A scaling design for a 30-router AS: chosen mechanism, reflector placement and redundancy, peer-group structure, and a written justification of the trade-offs
Multiprotocol BGP and Address Families (IPv6, VPN, EVPN)
Explain MP-BGP and the role of MP_REACH_NLRI and MP_UNREACH_NLRI in carrying non-IPv4 address families
Describe how IPv6 unicast is enabled per neighbor and how next-hop handling differs from IPv4
Explain the VPNv4 route distinguisher and route target roles and trace a route from a VRF into the global table and back
Describe at a high level how EVPN uses BGP to distribute MAC and IP reachability and name the main route types
Your checkpoint
A written walkthrough of one VPNv4 route and one EVPN MAC route from originator to consumer, naming each attribute and address family involved
BGP Convergence, Timers, and Stability Mechanisms
Compare Keepalive, Hold, ConnectRetry, and MinRouteAdvertisementInterval and state the effect of each on detection time and churn
Explain route dampening, its parameters, and why it is often avoided in modern designs
Describe BGP graceful restart and long-lived graceful restart and what each preserves
Predict the convergence behavior of a two-path topology when one path fails, with and without additional-paths or BFD
Your checkpoint
A stability configuration checklist for a production edge covering timers, BFD, maximum-prefix, dampening decision, and graceful restart, each with a one-line rationale
Service Provider BGP Design and Troubleshooting & BGP Path Selection and Best-Path Decision & Route Advertisement, Filtering, and Policy
Assemble a complete SP edge design covering addressing, peering types, filtering, best-path manipulation, and scaling
Diagnose five mixed symptom scenarios that combine session, policy, and best-path faults
Reproduce the best-path order and the main attribute categories from memory without notes
Identify your three weakest objectives from the prior seven weeks and close each with a targeted review
Your checkpoint
A full mock exam attempt plus a written post-mortem listing each missed objective, its root cause, and the corrective action taken
Milestones
Week 2: Without notes, write the complete best-path selection order and correctly resolve three of four route-comparison tie-break scenarios
Week 4: Given a session symptom, name the likely cause and the first two verification commands within 60 seconds, for three of three scenarios
Week 6: Explain the difference between a route distinguisher and a route target, and trace a VPNv4 route end to end, without reference material
Week 8: Score at least 80 percent on the mock exam and show a written post-mortem covering every missed objective