IonaParnell919

出典: くみこみックス

When you happen to be studying to pass the BSCI exam and earn your CCNP certification, you are going to be introduced to ISIS. ISIS and OSPF are both link-state protocols, but ISIS functions fairly differently from OSPF. You should master these facts in order to earn your CCNP. 1 of the significant differences amongst OSPF and ISIS will be evident to you when you 1st begin your BSCI exam studies, and that is the terminology. ISIS makes use of terms that no other protocol you've studied to date utilizes, and understanding these new terms is the first step to BSCI and CCNP exam success. 1st off, what does "IS" stand for in "ISIS"? It stands for "Intermediate Method", which sounds like a group of routers. As opposed to Autonomous Systems, which are logical groups of routers, an Intermediate System is basically a single router. That's it. You are going to also become familiar with Finish Systems, referred to in ISIS as an "ES". The Finish Technique is merely an finish host. ISIS and OSPF both use the concept of areas, but ISIS takes a various method to this idea. ISIS routers use three distinct types of routing levels, according to the place a router has been placed in. Level 2 routers are linked only to the backbone and serve as a transit device in between non-backbone locations. Level 1 routers are completely internal to a non-backbone place. enagic ISIS makes use of each Level-1 and Level-two Hellos, which means that the two types of routers just mentioned can not type an adjacency. Fortunately for us, there is a middle ground, and that is the Level 1-2 router. These routers connect non-backbone places to backbone areas. L1-L2 routers preserve two separate routing tables, one for L1 routing and one more for L2 routing. This is the default setting for a Cisco router, and L1-L2 routers can type adjacencies with both L1 and L2 routers. image what is an ionizer Part of the challenge of understanding ISIS is finding used to the differences in between ISIS and OSPF. Keep studying the terminology, master a single idea at a time, and soon you will be a master of ISIS and a CCNP to boot!