Nokia BGP for Internet Routing study plan

Explain from memory each BGP message type (OPEN, UPDATE, NOTIFICATION, KEEPALIVE, ROUTE-REFRESH) and the exact state machine transitions FSM passes through from Idle to Established

Describe how NLRI, path attributes, and the fixed 19-byte header with its length/type fields are encoded in an UPDATE, and why multiple prefixes can share one UPDATE

Compare iBGP and eBGP behavior: next-hop handling, AS_PATH prepending, TTL, loop prevention, and the requirement for a full mesh inside an AS

Configure two eBGP neighbors and one iBGP neighbor on Nokia SR OS with explicit peer-as, local-address, and import/export policies, then verify sessions reach Established with show commands

Diagnose a session stuck in Active or Connect by reading SR OS neighbor state output and identifying the missing or mismatched parameter

Rank the BGP best-path steps in exact order, including weight, local preference, locally originated, AS_PATH length, origin, MED, eBGP over iBGP, IGP metric to next hop, and tie-breakers

Predict the winner for at least six constructed prefix scenarios where each scenario differs in only one attribute

Explain why an SR OS implementation may evaluate weight or local preference differently from other vendors, and where the decision boundary sits

Distinguish deterministic MED, always-compare-MED, and default MED comparison, and state when each changes the outcome

Trace a full decision for one prefix using SR OS show router bgp routes detail output, naming each step that was evaluated

Build import and export policies in SR OS that set local preference, prepend AS_PATH, and modify MED, and confirm the effect on the Loc-RIB and Adj-RIB-Out

Explain the difference between well-known mandatory, well-known discretionary, optional transitive, and optional non-transitive attributes and give an example of each

Construct a community scheme (for example no-export, no-advertise, and site-specific tags) and apply it with policy match and action entries

Describe how NEXT_HOP is rewritten on eBGP export and why an iBGP router may need a next-hop-self policy

Use route reflection or explicit policy to control which prefixes leave an AS, and verify with show router bgp routes advertised

Explain route reflector cluster design, ORIGINATOR_ID and CLUSTER_LIST loop prevention, and when a client-to-client reflection is allowed

Compare route reflectors with confederations on configuration complexity, policy visibility, and scaling limits

Describe BGP timers (Keepalive, Hold, ConnectRetry, MinRouteAdvertisementInterval) and the effect of each on convergence and session stability

Configure a route reflector with two clients and one non-client in SR OS and verify reflected routes carry ORIGINATOR_ID

Tune advertisement interval and hold timers in the lab and measure the change in convergence time for a withdrawn prefix

Design a multihoming scheme that prefers one ISP for inbound and outbound traffic using local preference, AS_PATH prepending, and MED, and justify each knob

Explain the limits of MED across AS boundaries and why it is not a reliable inbound traffic-engineering tool between different providers

Build a prefix filter and an AS_PATH filter (including bogon and own-prefix filters) and apply them inbound on every eBGP session

Describe RPKI origin validation states (valid, invalid, not found) and how a router uses them in policy

Explain TCP MD5, TTL security (GTSM), and maximum-prefix limits as protective measures, and state what each does and does not stop

Explain multiprotocol BGP extensions: MP_REACH_NLRI, MP_UNREACH_NLRI, and how AFI/SAFI identify IPv6 unicast versus other families

Configure an IPv6 eBGP session in SR OS using the ipv6 address family and confirm IPv6 prefixes appear in the BGP table

Describe how next-hop handling and link-local addressing work for IPv6 BGP sessions

Review the BGP Fundamentals domain at a deeper level: route refresh capability, graceful restart, and their negotiation in OPEN

Identify three common causes of an IPv6 session failing to establish that do not occur in IPv4

Map SR OS BGP configuration hierarchy (router bgp, group, neighbor, afi-safi blocks) and explain inheritance from group to neighbor

Use at least eight SR OS show and debug commands to inspect neighbor state, received and advertised routes, policy results, and update statistics

Interpret common SR OS log and trap events for BGP session flaps and identify the root cause from the event text

Perform a policy troubleshooting exercise: given a prefix that is not being advertised, isolate whether the cause is policy, next-hop reachability, or session state

Explain SR OS commit, candidate configuration, and rollback behavior as they apply to BGP changes in production

Complete a timed 60-question mixed-domain practice set and score at least 80 percent

Re-derive the full best-path order and the attribute type table from memory without notes

Re-run the two weakest lab exercises from weeks 1 through 7 and confirm correct output

Write a one-page summary of the five concepts you got wrong most often, with the corrected reasoning for each