IPv6 address-type dictionary

During my IPv6 journey, I have encountered various descriptions/types of IPv6 addresses (temporary, link-local, anycast, preferred ..etc.) It was not easy to locate all of these, so I created my (ever updating) dictionary. (see my IPv6 course) “preferred address” as defined in rfc 4862: Used …”To handle the expiration of address bindings gracefully..” ..”Initially, an address is “preferred”, meaning that its use in arbitrary communication is  unrestricted. Later, an address becomes “deprecated” in anticipation that its current  interface binding will become invalid”.  “temporary address” described in rfc 4941 – “Privacy Extensions for Stateless Address Autoconfiguration in IPv6”. Temporary address is use to “makes it more difficult for eavesdroppers and other information collectors to identify when different addresses used in different transactions actually correspond to the same node”. Temporary IPv6 addresses are also referred to by DHCPv6 (rfc 3315) with the … Continue reading

IPv6 local routing

IPv6 behaves differently from IPv4 on local networks. ICMPv6 mechanism breaks the connection between assigning an address assignment, and using a prefix for routing/forwarding decisions. This article sheds some light on this new approach. (a guide to rfc 5942) IPv6 Local Networks In the IPv4 world, configuring an ipv4 address on an interface means also that the matching (sub)network prefix is directly connected through this interface. The process of assigning an address, and configuring a local network prefix is the same process. For IPv6 this is a little problematic. Suppose an ISP (Internet Service Provider) is connected to a subscribers,and the subscribers’ CPE (customer premise equipment) is configured in a bridged mode (refer to the top image). This means that the ISP can use a single prefix to assign addresses to more than a single subscriber. But then subscribers will … Continue reading

front end developer – 2016

Front end developer (or front end web developer) is not a new term now. 2012 is in the past now, but front programmers are still in demand. Problem is, more skills are needed, and you need to prepare yourself better than before. I’m buildint this page as an on-going guide for front-end developers. What is needed remarks subject Needed as ever. Current version is 5. This is: – a new version of the HTML language – a set of technologies that allows more diverse and powerful Web sites and applications.  HTML Javascript is the most important skill for a front end developer. This language is misleading: Javascript if not simple !!! It is the basis for all front end web programming: – web site (and web application) programming – hybrid mobile application programming (using a framework line phonegap/cordova or other) – server and desktop programming. … Continue reading

AngularJS Lesson 2: model-view-cotroller or MVC

We are talking about a rather old concept (MVC was developed during the 70’s for Smalltalk language) where one seperates between: the data of the application (model) the logic (controller) display of the data (view) This way it is possible to change the view of some data without changing the logic that controlls its value. MVC in AngularJS Data (i.e. model) can be even simple Javascript variables. for example:

AngularJS stores these variables in a structure called $scope (behund the scene this is just a regular JS object). Usually these variables are also kept inside another object (for reasons we will meet later):

View in AngularJS is a par of an HTML page. Example:

Notice that the view contains new tags that are not part of HTML. These tags came with AngularJS (and are called directives). Controller is … Continue reading

AngularJS lesson1: single-page applications

how internet pages are created Web sites create their pages in the server, combining them from html parts created using data from a database, and making server decisions using code stored in the server. When the product (which is an html page) is complete, the server sends the html code to the client (that is an html browser) and there it is loaded and displayed. sunstantial part of the “wisdom” of the site is done in the server that is taking care of interrcting with the user by creating menus, responding to input etc. single page applications Single page applications can do all that, but in general they work differently. In single page apps, html code  is created inside the client using Javascript, or is downloaded once from the server. Now, the server support the client by supplying data when needed, … Continue reading

Installing Phonegap on Window-7 (part 1)

Phonegap is an Adobe project, based on (and almost identical to) the open source project Apache Cordova. As we’ll see later, Installing both projects is almost identical.  NodeJS NodeJS ia a server side program that enables writing Javascript programs. In this case, we’ll use NodeJS locally, as one of the tools in Phonegap set of tools. mainly we’re after a package manager tool called npm that will help us install more later. Installing NodeJS is simple:  just download the installaion file from NodeJS site, (by pressing INSTALL on the main page) save the file in whatever directory and run it. No options to choose, no changes.  Installing GIT GIT is a version control tool created by Linus Torvalds, to manage the Linux source code. GIT let us get remote source from repositories, and that’s exactly what it’ll do for us later. … Continue reading