Broadband Advisor

• Fast connections are worth sharing
• Routing is the core of your shared network
• Dedicated devices - the alternatives
• What are the individual functions that make up the device?
• Buying a modem/router/switch
• Buying a device with an Ethernet switch
• Buying a device with wireless networking
• What about security?
• DIY vs ISP?
• Summary of features
• ADSL
• USB or Ethernet?

Intrusion Detection Systems: Intrusion detection systems are sometimes built into routers, providing real time analysis of inbound and outbound data packets, looking for suspicious patterns or activity. There are a range of techniques covered by the definition of IDS, although most routers simply detect suspicious events that meet predefined criteria and log them to a file. This is referred to as a passive system, whereas an active system would detect the potential security breach, trigger an alert and possibly ban the source IP address either temporarily or permanently.

IPSec: IPSec is an encrypted protocol commonly used by VPN connections. Whereas PKI is used to encrypt information passing between two computers at the data layer, IPSec encrypts the individual data packets at the IP layer. In Tunnel mode, the entire packet is encrypted, including the header information which contains information about the packet. In Transport mode, IPSec encrypts only the data within the packet, leaving the header intact.

PPTP, L2F and L2TP: The Point to Point Tunneling Protocol (PPTP) is a technology developed largely by Microsoft to allow VPN capabilities in Windows operating systems. Layer Two Forwarding (L2F) is a similar protocol developed by Cisco for similar purposes. Layer Two Tunneling Protocol (L2TP) is a more recent VPN technology emerging from the collaboration between Microsoft and Cisco to develop a compatible protocol that integrates the better aspects of both L2F and PPTP.

DIY vs ISP?

Many ISPs offer bundled hardware packages for use with their broadband services. The benefit of going with this option is that you are guaranteed to get devices that are compatible with your provider. Plus, if you do have any difficulties, you will get some level of service, although possibly at a fee. Doing it yourself, however, means you have the flexibility to choose exactly the equipment you need at the best possible price. Compatibility isn't too much of an issue when it comes to Australian ADSL services, as all of them support either PPPoE or PPPoA, and many support both. As long as the modem you buy supports the protocol used by your provider, it should work. Plus, if you build your network yourself, you will have a better idea of how to fix it should you experience any problems.