 It is important to understand that although NM as we know is there as a mechanism to allow the availability of telephone numbers but it is also important to appreciate how the market has adopted NM and the journey that NM has traveled to become the de facto standard for the NGN. So we'll start with the drivers that led to the emergence of NM as an acceptable mechanism and then we briefly discuss some security concerns that surround NM. First the backward compatibility. For sure users continue to have telephone lines, mobile phones and hence the telephone numbers. So the telephone numbers will not go away and would remain as key identifiers for at least the telecom services. The increased use of NM actually is an excellent way to prolong the lifespan of telephone numbers. It means that now we are not looking at telephone numbers as something that we would like to shelf, instead we are looking at it as something that will stay with us and that is going to give us due services and functionality. As far as the number plans are concerned if you recall once we were using pure telecommunication assigned numbers they were quite rigid and they were based on the localities and the suburbs where we would reside. Here because of the convergence to IP there is an increasing detachment of the number from the location from the group of users from the services that were tied to the telephone numbers. So there is a need for increased flexibility not only with regards to the options that are associated with the telephone number but also with the numbering plans which the users seek. So if there is no flexibility on the user end to have a choice to select a certain kind of telephone number it means that the user would always try to seek an alternative and nobody would like to do that. So consequently the telecommunication service providers are increasingly trying to make flexible numbering plans. With a telephone number it is also important to understand that if we have one single telephone number and against that telephone number we can have a variety of services that we can associate that would further make the telephone number critical and important and it's going to stay with us. Then another important issue is the personal allocation to end users. Typically we saw that in the typical households there was one telephone number per household but with increasing flexibility that the users demand each individual user might be as well interested in having a telephone number of his or her own while residing in the same household. And lastly there is always a requirement to have a flexibility to have the telephone number that can be ported between services. So it means a single telephone number can represent any service at a particular instance of time. Now let's understand what has been the most important area with regards to the adoption of Inam. First of all Inam started getting significant attention and interest when voice over IP based applications and services were introduced in NGN. And there's a reason for that because voice over IP services are usually independent of the physical location and are also independent of the household or the per household basis. So the overall drivers that we saw in the last slide are very much applicable to the voice over IP communication scenario. Likewise the new voice over IP carriers actually try using this Inam along with SIP as an alternative to signaling standard 7. Signaling standard 7 as we all know is the signaling standard for the PSTN and PLMN networks. So in SS7 there's a dedicated network that comprises certain nodes which allow the transmission of the control signals. So with this emergence of Inam, we can now think about integrating it with SIP to do us the functionality what SS7 used to do alone. Because of the variety of Inam that is both public and carrier, some security and privacy issues do emerge. Especially in public Inam since an individual user is at liberty to reveal or associate virtually any information with his or her telephone number. So a whole set of interesting privacy and security vulnerabilities emerge. Of course, this data gets published on the internet. If it is with regards to an individual, it is risky for that individual. But if it regards to the carrier Inam or aka the infrastructure Inam, the problem is more significant because now we are talking about peering carriers that are exchanging information between each other for a group of users. So the solutions are not limited to, but solutions are related to authentication and authorization mechanisms that are overlaid in DNS, something called DNSSEC or DNS security measures. It is currently beyond the scope, but it's always an interesting way to explore what DNSSEC is about with regards to the Inam security.