Unit 1: Network Infrastructure
This will allow you to demonstrate your networking skills, knowledge, and abilities, with a focus on enterprise-level switching, routing, and multicast components that support cross-platform (inter)operability and integration with the most recent software-defined technologies.
As is the case with IP addresses, Autonomous System Numbers (ASNs) are required to be indistinguishable from one another on the Internet. The primary reason for this is that the AS number is utilized by BGP as part of its method for preventing loop accumulation. When the Border Gateway Protocol (BGP) discovers a route that contains its own AS number in its path, the route will be discarded.
This is an example:
In the example above, two of the routers, R1 and R3, are sharing an AS number. Since the AS numbers are identical, R2 will accept the update sent by R1, but R3 will reject it.
For this reason, the Internet Assigned Numbers Authority (IANA) oversees the allocation of AS numbers, which are analogous to public IP addresses. You are need to submit a request in order to obtain an AS number for the Internet. They began with 16-bit AS numbers, which were assigned in the following way:
