 Now, we are going to look at the mobile YMAX network architecture. This architecture includes certain components and their interaction pretty much similar to what we have seen earlier in the 3GPP architecture. The YMAX forum has defined the overall architecture because IEEE had only focused on the physical and the data link layer. So YMAX forum has encompassed all these layers and whatever functionality the network is supposed to provide for these layers. The architecture for mobile YMAX release 1.0 and 1.x it means the other variants 1.1 and so forth and mobile YMAX 2.x is essentially the same. The only difference being mobile YMAX 1 is based on IEEE 802.16e and the version 2 is based on M. So this consequently translates into a change in the physical and data link layers of the mobile stations as well as the network elements. So the user equipment or the mobile stations would now differ. In the earlier version it was the mobile station in the more advanced 2.0 mobile YMAX it is advanced mobile stations. Let's look at the overall architecture starting from the leftmost side where we have the air interface or the user equipment. You see we have either mobile stations here or we have advanced mobile stations. Then we have the access service network that is the access side of the network architecture. Here we have either the base stations or we have advanced base stations. This difference in terminology essentially implies to better modulation and multiplexing schemes, revised packet structure, packet handling and the software components which handle these packets and traffic. Then we have the access service network gateways which provide connectivity between the mobile station and the connectivity service network. The connectivity service network is more or less the core network side that hosts servers which are responsible for providing both bearer paths as well as the bearer channels, bearer paths and the signaling network. So we see here we have the mobile stations, we have the access side, we have the connectivity side with a lot of application servers and other kinds of network management servers. So this is what we conclude, we have the mobile stations, the access service network and the connectivity service network. Just going a little more into detail on the access service network, this is like radio access network in 3GPP. It comprises homey node bees if you may of YMAX. So here the entities or the modules which provide services to the mobile station are either the signaling service and the data service. Signalling service actually is for managing and controlling the mobile station. It involves functionalities starting from authentication, the triple A services, the distribution of keys, qualitative service enforcement, queuing, scheduling, etc. Mobility management when a mobile station or a user equipment leaves one network, premises enter into the other and maintaining the connectivity. So once this control entity is done with its functionality, then the bearer path or the data path is established between the mobile station and the internet. Then we have the connectivity service network. Here connectivity implies the IP connectivity because the radio connectivity has already been taken care of by the ASN. So the CSN like the evolved packet core is all IP based. It involves all these different kinds of servers. Now the connectivity service network is responsible to provide services to the ASN which in turn is providing services to the mobile station. So indirectly CSN is providing the external IP connectivity, the public IP cloud to the mobile station.