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Showing posts from December, 2016

How to show Loader for $http calls in AngularJs ?

Hello Readers !!  In this post we are going to see how we can add a loader for $http calls in our angular applications. This loader will be shown whenever our angular application will send some call to server. I am assuming that you are aware of basics of AngularJs,  if not then please go through the AngularJs official Developer Documentation. So, lets begin, first of all we will be making simple loader UI with HTML and CSS . So our HTML will look somewhat as shown below. <div id="loader" class="loader" loading> <span class="fa fa-spinner fa-pulse fa-2x fa-fw loader-align"></span></div> Here I have used font-awsome’s spinner icon . You can keep same or can build your own loader/spinner, somewhat like this . Now let’s move to CSS part. Our loader should cover whole area of page and should not allow any actions unless all calls to server are finish. All we need to have div which will be having height and width 100% and z-inde

What is IP address "overlapping" within the context of NAT ?

IP address overlapping refers to a situation where two locations that want to interconnect are both using the same IP address scheme. This is not an unusual occurrence; it often happens when companies merge or are acquired. Without special support, the two locations will not be able to connect and establish sessions. The overlapped IP address can be a public address assigned to another company, a private address assigned to another company, or can come from the range of private addresses as defined in RFC 1918 . Private IP addresses are unroutable and require NAT translations to allow connections to the outside world. The solution involves intercepting Domain Name System (DNS) name-query responses from the outside to the inside, setting up a translation for the outside address, and fixing up the DNS response before forwarding it to the inside host. A DNS server is required to be involved on both sides of the NAT device to resolve users wanting to have connection between both networks.

What is Service Provider PAT Port Allocation Enhancement for RTP and RTCP?

The Service Provider PAT Port Allocation Enhancement for RTP and RTCP feature ensures that for SIP, H.323, and Skinny voice calls. The port numbers used for RTP streams are even port numbers and the RTCP streams are the next subsequent odd port number. The port number is translated to a number within the range specified conforming to RFC-1889. A call with a port number within the range will result in a PAT translation to another port number within this range. Likewise, a PAT translation for a port number outside this range will not result in a translation to a number within the given range.