#Ip summary route calculator how to
#Ip summary route calculator manual
#Ip summary route calculator plus

More examples to follow, once I show some practice problems. Here’s the process, without a lot of embellishment, followed by 1 example. I’ll show the process in a few upcoming examples in some practice problems.

#Ip summary route calculator how to

If you have a method you already like, use it! Ignore what is here! But if you want to see another method, I’ve got a shorthand method of how to do it listed here. You can use many methods to find the best summary route. However, a summary route based on subnet 172.16.0.0/22 also includes all the addresses in those original three subnets, but not many others. The earlier answer, 172.16.0.0/16, means “all addresses that begin 172.16”, which is far more addresses than the addresses in those three subnets. For instance, with the earlier example, 172.16.0.0/16 includes all the addresses in the original three subnets, but the summary route includes many other addresses as well.įor example, consider the best summary route for those earlier three subnets: 172.16.1.0/24, 172.16.2.0/24, and 172.16.3.0/24. However, for CCNA, best summary generally means the summary route that includes all the addresses in the original subnets, but is the smallest such subnet. To determine the best summary route – in other words, the best subnet/mask combo to advertise as a summary – you need to think about the goals of a given network. Many possible summary routes exist for a given set of routes.

#Ip summary route calculator plus

For instance, if a router had routes for subnets 172.16.1.0/24, 172.16.2.0/24, and 172.16.3.0/24, you could advertise a summary route for subnet 172.16.0.0/16, because it represents a superset of original three subnets, in that it includes all the addresses in the original three subnets, plus some others.

#Ip summary route calculator manual

The term manual summary route refers to the fact that the summary route requires a configuration command that the engineer must type on some router.įor the CCNA exam, you need to be ready to look at a set of routes in a router’s routing table, and find a larger subnet/mask combination that could be configured as a summary route. That summary route represents a superset of the range of addresses compared to the original routes. Instead of advertising those multiple routes for smaller subnets, the router instead advertises that one summary route. The range of addresses that match that single route includes the same addresses in multiple other subnets in a router’s routing table. Ask questions if you have them!Ī summary route, sometimes called a manual summary route, is a route advertisement that lists a single route. Other later posts then give you some practice problems. What does that mean, and how do you do it? Today’s post hits the highlights at least, and points to more info. Today’s post sets up the topic of how to find a “best” summary route.