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What is wide metric?
EIGRP wide metrics supports interfaces up to 4.2 terabits and uses a different composite cost metric formula. It has the following components: Throughput: this is the bandwidth, it uses a new scaled bandwidth formula. Latency: this is the delay, in picoseconds. 1000000000 picoseconds = 1 millisecond.
What is OSPF metric?
The OSPF metric for a route is the sum of the interface costs for all outgoing interfaces in the route. By default, a router’s OSPF interface cost is actually derived from the interface bandwidth: The faster the bandwidth, the lower the cost. OSPF considers the costs of the outgoing interfaces (only) in each route.
IS-IS link state PDU?
Link-state PDUs—Contain information about the state of adjacencies to neighboring IS-IS systems. Link-state PDUs are flooded periodically throughout an area. Contained within the CSNP is a link-state PDU identifier, a lifetime, a sequence number, and a checksum for each entry in the database.
Is router a type?
There are only two network types in IS-IS. Broadcast and Point-to-Point. Broadcast is default network type. If one end is configured with “isis network point-to-point” and other end is default network type.
What metric is used for RIP?
hop count
Routing Information Protocol (RIP) uses hop count as the metric to rate the value of different routes. The hop count is the number of devices that can be traversed in a route. A directly connected network has a metric of zero; an unreachable network has a metric of 16.
IS-IS routing protocol vs OSPF?
Both IS-IS and Open Shortest Path First (OSPF) are link-state protocols, and both use the same Dijkstra algorithm for computing the best path through the network. While OSPF was natively built to route IP and is itself a Layer 3 protocol that runs on top of IP, IS-IS is an OSI Layer 2 protocol.
How are is-is metrics calculated in traffic engineering?
Routes with lower total path metrics are preferred over those with higher path metrics. Unlike OSPF, in which the link metric is calculated automatically based on bandwidth, there is no automatic calculation for IS-IS. All IS-IS links use a metric of 10 by default. Normally, IS-IS metrics can have values up to 63.
Why does juniper advertise both old and new metrics?
By default, Juniper will advertise both old-style and new-style TLVs (wide-metrics is on by default). By in large, this default was made for networks that were in the middle of transitioning to the new-style functionality. Enabling wide-metrics-only simply tells IS-IS to suppress old-style TLVs.
How to use wide metrics in is-is?
By default, Junos OS supports the sending and receiving of wide metrics. Junos OS allows a maximum metric value of 63 and generates both pairs of TLVs. To configure IS-IS to generate only the new pair of TLVs and thus to allow the wider range of metric values, you must include the wide-metrics-only statement in the IS-IS configuration.
What happens when Junos is configured as wide metric only?
By default, Junos generates and accepts both wide and narrow style TLV`s. TLVs 2,22,128,134,and 135 are all present. When wide-metrics-only is configured for a level, Junos suppresses the generation of narrow-style-metric TLV`s.