JNCIS-SP case studies
JNCIS-SP · Put your knowledge to work in context.
The Juniper Networks Certified Internet Specialist – Service Provider Routing and Switching (JNCIS-SP) is a mid-tier certification for network engineers who design, build, and operate service provider infrastructures on Junos OS. It sits above the associate-level JNCIA-Junos and below the professional JNCIP-SP, so it is the natural stepping stone for engineers moving from device-level configuration into protocol-level troubleshooting. The JNCIS-SP case studies are 5 cases and about 4,558 words.
1Totally Stubby Area Blocks the Customer's Redistributed Routes
A provider runs OSPF with area 0 in the core and area 51 for a managed customer edge. Two ABRs, PE-A and PE-B, sit between area 0 and area 51.
834 words, about 4 min2Level 1 Default Routing Sends Metro Traffic the Long Way
An ISP runs IS-IS with L1 areas 49.0001 (metro A, 60 routers) and 49.0002 (metro B, 35 routers) plus an L2 backbone. CR-1 and CR-2 are L1/L2 routers, each with an L1 link into metro A and an L2 link to the backbone.
907 words, about 5 min3Route Reflectors, Equal Local Preference, and a 70/30 Egress Split
AS 65010 has two border routers, BR-1 and BR-2, each with eBGP to a different transit provider. Both are route reflectors for 14 PE routers in a single cluster.
899 words, about 4 min4Dual Transport LSPs and a Hub-and-Spoke Route Target Design
A provider runs LDP between four P routers and two PE routers, PE-1 and PE-2. Two VPNs share the core: VPN-Red (route target 65100:100) and VPN-Blue (65100:200).
957 words, about 5 min5Dual-Homed Access Switch, STP Root, LAG and a Reload
A metro Ethernet edge uses two aggregation switches, AGG-1 and AGG-2, joined by a 2 x 10G bundle, each with one 10G link to access switch ACC-1. ACC-1 carries VLANs 100, 200 and 300 on a trunk to both AGGs.
961 words, about 5 min