Intra-AS refers to an internal autonomous system in which routing is internal to the autonomous system alone but completely invisible to those outside of it. That being said it is NOT necessary for every autonomous system to use the same intra-AS routing algorithm, because each one has administrative autonomy for routing within any autonomous system.
It is a wireless networking standard.It functions only on 5 Ghz only. 802.11ac has three times the bandwidth of 802.11n hence it can handle more number of users.It has multi-link throughput of 1 gigabit per second.It provides high throughput.It is very useful for environments with high user density.
