FAQ Connections

• Modem, Cable, DSL, LAN Connections
• AOL, CompuServe and similar ISP connections
• Transmission times/Backup tips
• Firewall information

Modem, Cable, DSL, LAN Connections

Each type of connection has its own characteristics. When our software is first installed it will identify the type of connection that you have and auto-configure itself to use it. If you have more than one connection, you can specify which one the software should use.

Standard modems have been in use for a long time and are consistently reliable. They open and close a connection as needed, using a dialler, unlike other methods of connecting. Our software supports the standard Windows Dial-Up-Networking for these modems.

Cable modems have certain limitations that could affect your connectivity. For example:

• Cable service can be either one-way or two-way, depending on the provider. One-way service relies on an analogue modem and phone line for uploads. This limits upload speed to 33.3 Kbps. The more people on a node, the slower each connection could be.
• Service providers can tie a specific data rate or percentage of total bandwidth to each user. Providers do move bandwidth around among users selectively.
• Since most users don't need constant-megabit-per-second connections - they need high speeds for loading a Web page but not for viewing it - cable operators will take advantage of this burst of usage and divide bandwidth among multiple users.

DSL service comes in several flavours, with varying throughput rates, technical limitations, and prices.

• Speed: The most common form for businesses and home users - the one we refer to simply as DSL - is asymmetric DSL, or ADSL, which supports peak downstream speeds of 144 Kbps to 2.2 Mbps but upstream rates only from 90 Kbps to 640 Kbps. Your backups will run at the upstream rate.
• Distance: The line's performance degrades with distance from the central office. All else being equal, users 5,000 feet from the central office will get better throughput than those 15,000 feet away. Beyond 18,000 feet service is generally unavailable.
• ISP: One advantage of ADSL service is a dedicated connection that won't degrade as more users in your area sign on (as cable will). Still, performance not only varies depending on how far you are from the central office but also on the efficiency of your ISP's network. Even the fastest DSL connections can't cure bottlenecks at an ISP, such as slowdowns during peak hours.
• Generally, DSL upload transmission speed is rated at an average of 256K. Therefore, a data stream of 100MB would upload in 54.50 minutes.

LAN connections, including DSL and cable, provide a continuously open channel to the Internet. Like DSL and cable, LANs do not necessarily assure a high rate of transmission. You still have to go through an Internet gateway and through several routers, so the variables that create bottlenecks still exist and can affect throughput.

AOL, CompuServe and similar ISP connections

If you will be connecting to us via ISPs who provide their own dialler instead of using the standard Windows dialler, it will be necessary to open your Internet connection before running our software. You will not be able to use scheduled backups that run automatically, but all other features are unaffected.

Transmission Times/Backup Tips

Some suggestions for successful backups:

• Avoid peak hours. We recommend using automatic backups that are scheduled to run in the earliest morning hours, between midnight and dawn.
• Close applications that aren't essential during the backup. There may be one or more background applications running at the same time. Use Windows Task Manager to check this.
• Monitor several transmissions to see the speed at which your ISP has connected you. Bandwidth is not usually guaranteed and will vary with the amount of traffic at any given time. Try to backup when conditions are favourable.
• Reduce the size of your backup sessions - at least until you complete an initial backup of everything that you want. It may be that your ISP's available capacity is being taxed by sheer volume or that your own network is.

Sample transmission rates:

Firewall Information

Firewalls can be implemented in several ways. If you have a firewall, you will need to configure it and/or the Backup Direct™ software to allow inbound and outbound transmission. How you do that depends on the type of firewall that you have.

SOCKS proxy firewall: In the Backup Direct™ software, provide your firewall's IP address and the port to use to connect to the firewall. That's it; you do not need to reconfigure your firewall.

Non-SOCKS-compliant firewall: You will need to configure both the Backup Direct™ software and your firewall. Contact your firewall administrator for assistance. Read our detailed firewall information.

Detailed Firewall Information: Overview
Protocols
Server Subnets
Port Numbers
DNS
Registration vs. subsequent connections
SOCKS-Compliant Proxy Servers
Other Proxy Firewalls
Packet Filtering Firewalls
 

Detailed Firewall Information: Overview

The Backup Direct™ software communicates with the Backup Direct™ secure Data Centres using the standard TCP/IP protocol.

Connections are initiated from the backup software on your computer or inside the firewall. Connections are NEVER initiated from the outside.

The program can work with all types of firewalls, including packet-filtering, circuit-filtering, SOCKS-compliant Proxy or Mapped Proxy firewalls. For most firewalls, some configuration of the firewall is needed. If your network requires explicit connection to the firewall to initiate outgoing connections, the Data Protector software must be configured for your firewall. You can configure it yourself using our client software configuration tool.

The requirements for running Backup Direct™ service are consistent with security best practices. They do not create an opening for incoming connections, and outgoing connections can be limited to specific ports at specific known IP addresses. As an added security measure, all data is Triple-DES encrypted before leaving your PC; it remains encrypted though transmission, and is stored encrypted at the Backup Direct™ secure Data Centres.

The following information is useful for configuring a firewall to permit outgoing connections to the Data Centre servers.

Protocols

TCP/IP is used. There is no use of UDP or ICMP.

Server Subnets

Each user's Backup Direct™ software connects to a primary and an alternate server in order to provide high availability. Currently, all servers reside in the following subnets:

• 193.239.112.0-255 (also expressed as 193.239.112.0/24)
• 193.239.113.0-255 (also expressed as 193.239.113.0/24)
• 194.79.242.0-63 (also expressed as 194.79.242.0/26)
• 194.79.243.0-63 (also expressed as 194.79.243.0/26)
• 194.79.240.0-63 (also expressed as 194.79.240.0/26)

The Backup Direct™ software must have access to these subnets. Should these addresses change in the future, notice will be given to allow firewall changes and the Backup Direct™ software can be automatically updated with the new addresses.

Port Numbers

All Backup Direct™ servers listen for client requests on a well-known port number: 16384. The Backup Direct™ software always establishes a TCP/IP session with port 16384 on the server.

DNS

The Backup Direct™ software connects to a server using the server's IP address, not its name. Therefore, name resolution and access to a name server are not required.

Registration vs. subsequent connections

The Backup Direct™ software is configured to connect to one of a pair of registration server addresses (primary and alternate) when it is used for the first time. The registration process assigns a server address pair (primary and alternate) for all subsequent uses.

SOCKS-Compliant Proxy Servers

The Backup Direct™ software can be configured to connect out through a SOCKS proxy server. The IP address (or the DNS) of the proxy server and the port number on which it listens for connections must be known in order to configure the backup software. SOCKS is designed to allow outgoing connections and responses back to those connections, but to prevent other incoming packets. This is consistent with the Backup Direct™ software. If your SOCKS proxy server has been set up with additional restrictions on outgoing connections, it is necessary to include Backup Direct™'s subnets in the permitted destinations.

When prompted by the Backup Direct™ setup program to select a Firewall option, select the, "Use SOCKS proxy firewall" radio button and enter your proxy server information.

Note: The default setting for SOCKS TCP Port is 1080.

Other Proxy Firewalls

In order for the Backup Direct™ software to be used with an application-based proxy firewall server, the firewall must be set to permit outbound TCP connections for a generic application. Mapped firewalls require a separate port on the firewall for each different destination address.

The IP addresses that must be mapped will appear when you attempt to run the client software, or can be seen by selecting Options/Connection.../Firewall in the client software. The destination port number is always 16384. The firewall administrator may choose any available port numbers on the firewall. Finally, the Backup Direct™ software must be configured with the IP address or the DNS of the firewall and the firewall port numbers that were chosen.

When prompted by the Backup Direct™ software to select a Firewall option, select the, "Use proxy firewall server(s)" radio button. Then enter the firewall mapping that was configured on your firewall: Enter the IP Address or DNS of your firewall into the "Firewall IP address" field; for both Secure Data Centres enter the port numbers chosen by the firewall administrator.

Packet filtering firewalls

The following is a summary of rules that must be applied to the firewall software or hardware in order to enable Backup Direct™'s client-server protocol. (All the rules are described from the 'firewall's point of view.')

• Permit TCP/IP outbound to port 16384 to subnets 193.239.112.0-255 (193.239.112.0/24), 193.239.113.0-255 (193.239.113.0/24), 194.79.242.0-63 (194.79.242.0/26), 194.79.243.0-63 (194.79.243.0/26), and 194.79.240.0-63 (194.79.240.0/26).
• If your firewall requires you to explicitly permit the response packets to come back, do so by permitting TCP/IP inbound to ports 1024-5000 from the subnets listed above, for an already-established connection. It is NOT necessary to permit a connection originating from outside the firewall.
• We do not utilize UDP or ICMP.