VPN Tunnelling and what Microsoft uses (PPTP)

Virtual Private Networks (VPNs) offer a cost effective alternative to other mechanisms to connect geographically distance offices such as leased lines (sometimes called "private circuit"), which involves paying a monthly lease to a provider in exchange for a permanent connection between two locations. A problem can be lack of guaranteed bandwidth which you get with a leased line.

The first form of VPNs were software defined networks (SDNs) developed by AT&T in the 1980s.

Today's technology relies on tunnelling protocols, the main ones being:

• IP Security (IPSec) which is an open standard that deals with authentication and security of transmission over the public network.
• PPTP or Point to Point Tunnelling Protocol, developed by an industry consortium including Microsoft and 3Com is used by Windows.
• Layer 2 Tunnel Protocol (L2TP) was developed by Cisco to replace IPSec

Tunnelling offers the safety and security required to make VPNs a viable proposition. It behaves like an envelope for letters - the data packet in the payload of another packet which follows another protocol. This technique also allows routing of non IP packets.

The tunneled packet header contacts a bunch of information relating to the protocol of the enclosed packet, the initiator and potentially a checksum to ensure data was not corrupted during transmission.

Pdf Files in Windows 8 and when not to use Windows Reader

Pdf files are opened automatically by Windows 8 Reader which has built in PDF support. This is neat for casual reading. The catch - not all features of PDFs are supported. Worse still, if you resave the file in Reader, you are likely to lose functionality. You may therefore need to install Adobe Reader and set the default PDF application on your files to link to Adobe.

Visual Studio Online

Visual Studio Online allows you to create projects online and is free for up to five users. It allows you to use Version Control, specifically git or Team Foundation. Additionally, it offers process templates including Scrum and Agile.

What's New in IE11

IE11 includes the so-called "F12 Developer Tools". It includes the DOM Explorer which includes expand and contract functionality on HTML nodes. It also includes a Debugger and Profiler.

Windows 8 Shortcuts (Including Command Prompt)

In what follows, WB stands for "Windows Button".

WB-C   -> Open Charms (Frequently used Windows Functions)
WB-E   -> Open File Manager
WB-R   -> Open Run (then type cmd to open Command Prompt)

Alt-F4 -> same as before (close current window)

Cntrl-Shift-Escape -> Task Manager

The Windows Client/Server Runtime Subsystem (CSRSS)

csrss.exe is a component of Windows NT family operating systems that runs the user mode (all code outside of the kernel) of the Win32 subsystem.

Image Path Name in Task Manager

We can check the Image Path Name in Task Manager.  Click on View then Select Column. It can be useful to see if common exe files are running from their expected locations. For example, rundll32.exe should run from C:\Windows\system32 or C:\WINNT\system32.