Actually few of the Entry Level Cable/DSL Routers, got SPI through Firmware upgrade, and most of the new el-cheappos comes with SPI and better support for VPN.
When it comes to the mid price Routers ($100-$200) some of them are just overpriced, and sold to businesses that don¡¦t ask questions. Some like the ZyWall 1 have better support for safety protocols.
However, one has to look at the list, and make sure that he needs the extras (like alerts via e-mail), and is it worth is while paying more.
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ZyWall 1 Pros, and Cons (source:
http://www.practicallynetworked.com/review.asp?pid=477).
Pros:
- Highly customizable
- Support for Dynamic DNS
- Detailed logging and alerts via e-mail
- Supports up to 50 VPN Tunnels (ZyWALL 50)
- Excellent content filtering
Cons:
- No auto-sensing ports
- User Guide on CD only
- No integrated switch (ZyWALL 50)
- Firewall rule creation can be confusing
ZyXEL designed both of these products to support numerous routing protocols. These include TCP/IP, RIP-1, RIP-2, ICMP, ARP, IP Multicast and IP Alias. An abundance of security protocols provide network users with even greater protection.
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BTW, to maintain perspective the ZyWall 50 which is a real power house is over $500.