The topics in this chapter deal with the traffic generated by the routing updates in terms of both the network resources that they use and the information contained within them. This covers two different but related areas. The network overhead involved in routing updates has already been dealt with in other chapters, and it keeps recurring as a theme because all network traffic directly influences the network's capability to scale or grow. The issue is very complex and deals with the design of the network and configuring around that design.
The information propagated through the network is complex when dealing with one routing protocol. When multiple protocols have to share information so that the larger network can see every route available within the routing domain, life can become very confused. At this point, the information flow must be controlled and managed very closely.
This chapter deals with these issues, focusing mainly on the configuration of redistribution and route filtering. This is founded in a conceptual explanation and a brief consideration of the design issues that may affect the configuration. The Routing exam will probably concentrate on the configuration commands because the other areas are very esoteric and are very dependent on the individual design of any given network.
The BSCN course devotes 16 percent of its material to redistribution and filtering, which is more than any other single subject is allocated. The majority of these BSCN pages are concerned with configuration, so it is fair to conclude that the exam may concentrate on this area.
One of the reasons that the course is concerned with redistribution is because the fundamentals of filtering comprise many of the calls to the telephone support group. In addition, the Routing exam is one of the steps to becoming a CCNP, a highly coveted title that tells the world that you have competency in the management of large networks. Many of these large networks have some level of redistribution, and nearly all contain route filtering in some form.
Was this article helpful?