We are conducting our lives and our businesses in an increasingly mobile world.  We need access to our critical business information from multiple locations and using multiple devices.

These needs often clash with the requirement to keep our data secure.  Exchange Servers are kept behind corporate firewalls which restrict who can access them and how they can connect to their mailboxes.

Secure mobile access to mailboxes on Exchange Servers is typically achieved through one or more of these methods:

• Virtual Private Network (VPN)
• Outlook Anywhere
• Outlook Web App (OWA)
• ActiveSync

Virtual Private Networks

A VPN is a secure communications tunnel established between two endpoints.  These endpoints can be two devices such as routers or firewalls, or can be between a client device such as a laptop and a firewall.

Mobile workers use VPNs to establish LAN-like network access to their corporate network.  This usually means that once connected to the VPN they have access to the same network resources they would be able to access when connected to the LAN from within the business premises.  In more security conscious environments this access is sometimes limited to just the few resources they need, but in a practical sense operates just as if they were on the LAN.

Using VPNs for access to Exchange Server makes sense when there are other needs for VPN access as well, such as access to application servers, file servers, or intranet sites.  Rather than each resource having its own independent access method, the VPN provides an “all in one” access solution.

However sometimes VPNs are not practical.  It is not uncommon for a mobile worker to find they are unable to establish a VPN tunnel because of restrictions on the foreign network they are currently working on.  This is mostly the case for IPSEC and PPTP VPN tunnels.  SSL VPN tunnels usually have no such problems because the SSL/HTTPS port is usually permitted out through firewalls.

Outlook Anywhere

Outlook Anywhere was formerly known as RPC-over-HTTPS, which accurately describes how it works.

The Outlook connection to a mailbox server over RPC is tunnelled through an SSL/HTTPS connection so that it can traverse firewalls, as well as to secure the communications over untrusted networks. Continue reading 4 Ways to Access Exchange Server Mailboxes through Firewalls

More and more companies are allowing employees to work from home via remote offices. Outfitted with high-speed internet, separate phone lines for fax and business calls and office white boards and most office workers are ready to be productive as if they were working in any office environment complete with interruptions – though not the usual kind.

One of the interruptions remote office employees will most often face is that of remote connectivity problems. The problem of a remote connection being down is that it is sometimes hard to pinpoint the exact cause of the remote connectivity issue.

For instance, users have reported remote connectivity problems when running Exchange 2003 on a Windows 2003 Enterprise Server. Remote users will experience “disconnected” status issues when connected remotely and Outlook will be displayed as being in “offline” mode. However, when users are in their company’s office they do not have any problems connecting to their Exchange mailbox while using Outlook 2007. And running in cached exchange mode does not appear to help either.

One of the first steps that an administrator should perform is to verify whether the Virtual Private Network (VPN) is working correctly or whether it is part of the problem. An administrator can bypass the VPN by configuring Outlook to communicate with the Exchange server via Remote Procedure Calls (RPC) over Hyper Text Transfer Protocol (HTTP). This will allow the administrator to confirm whether the remote communication problem still exists even when not using a VPN connection. If there is still a remote connection issue, while running RPC over HTTP, then the administrator will know that VPN is not part of the problem.

Continue reading Troubleshooting Unavailable Exchange Server

Virtual Desktop Interfaces like GoToMyPC can be more secure than VPNs for remote workers.

As workers become increasingly mobile, they’re demanding access to their computers–both at home and in the office–from whereever they can connect to the Internet. Cube rats want to access their home computers. Road warriors need to connect to their office desktops to maintain their productivity while traveling. Linking to headquarters is essential for telecommuters.

Over the last decade or so, the vehicle for establishing secure connections outside a company’s firewalls has been the Virtual Private Network, or VPN. It allows a remote computer to tap into a corporate network by creating a secure tunnel to it through the Internet. This method, though, can have security risks. That’s opened a market for alternatives to the hoary VPN.

Because VPNs originate with a company’s IT department, their operation is unquestioned by their users. After all, the reason users are told they need to use the VPN is so they can connect to headquarters securely. That creates a false sense of safety among users so they’re likely to transfer sensitive data through the VPN without using additional encryption and deploy protocols that transmit authentication credentials without any protection at all.

Continue reading More secure alternative to VPN

In another post I spoke of VPN and using secret keys to secure communications. VPN stands for Virtual Private Network and if you work for a large company or do business with a large company then chances are you log in to your network via a Virtual Private Network. A VPN is a network within a larger network such as the Internet or a company LAN. But the VPN is not characterized by the physical wires. Instead the VPN uses open connections or virtual circuits through the larger network.

VPNs can enable secure communications over the public network by using authentication or encryption. One of the ways to secure communications of the VPN is by using what is known as IPSec.

IPSec is short for IP security and is a secure VPN protocol. IPSec is defined by the Internet Engineering Task Force.

Continue reading How to secure your network using IPSec