PC300 - The Router Killer
Marcio Saito - V_1.2.0 April 2000
About this document
The Cyclades-PC300 or simply PC300 is a synchronous board that can be installed in any available PCI slot of a server. It provides WAN connectivity with point-to-point leased lines or switched networks (Frame Relay and X.25). This document discusses how the PC300 can be used to replace an external router, with
potential cost and integration advantages. The PC300 is compatible with Linux servers running on standard PCs or network appliances such as the Cobalt Qube. It supports PPP, Frame Relay, HDLC and X.25 protocols.
Stand-alone or server-based Networking?
A router is a networking box that connects the Local Area Network (LAN) to the Wide Area Network (WAN). It does that by routing packages between its interfaces based on the information provided by the network protocol. This paper focuses on the case where a small- or medium-sized network needs connection to a central site (either the corporate headquarters or an Internet Service Provider) over
the WAN (typically a T1 leased line, fractional T1 leased line, or Frame Relay connection). A traditional router is a stand-alone box, usually with proprietary hardware and software, that has one or more LAN interfaces and one or more WAN interfaces.
The Networking Operating System running in the server is typically Windows, Linux or some variety of Unix. All those operating systems incoporate a complete TCP/IP protocol stack and, therefore, can perform the IP routing function. More than that, with the importance of networking on today's computing environment, the protocol stacks available withing the OS have become very
sophisticated and have features that, in many cases, match or supersede the features available in proprietary boxes. If the server had a WAN interface, it could connect directly to the communication line and, that way, we would eliminate the need for an external router. The Cyclades-PC300 is a PCI adapter that, when installed in a server, provides the WAN interface necessary to do that.
Using servers to perform the functions previously allocated to dedicated networking boxes is what we call server-based networking.
A server-based solution has some appealing advantages, especially for small- and medium-sized organizations:
· Low cost. Server CPU power is becoming extremely inexpensive because of the commoditization of PC hardware. Besides this, the server must be present whether you have an external router or not. Not considering the cost of the server, the Cyclades-PC300 is up to 75% less expensive than a solution based on an external box. ·
High integration and simplicity. Having the server performing routing functions eliminates the need to manage an additional physical box. Besides that, the user can implement the network configuration within the familiar Operating System environment. There is no need for training and support of one additional operating environment.
There are other scenarios where the PC300 offers a better solution than external routers:
Network Appliances. There is a new generation of products taking advantage of the availability of commodity hardware and open source software to target small- and medium-sized organizations with simple, easy-to-install Internet gateways. One example of such product is the Cobalt Qube. The use of an external router with network appliances goes against the concept of integrated, simple, and
easy-to-install solutions.
Communication Systems. Many companies are building sophisticated communication systems using industry-standard components. The PC300 allows them to add WAN routing capabilities to the system without sacrificing integration and the cost of the total solution.
Of course, server-based networking is not the right answer for every situation.
In applications where extremely high reliability and availability is required, a solution based on a general purpose PC server responsible for other functions besides the networking itself may not be the best solution.
There is a limit on the scalability of a server-based solution. In a very large network where a site needs more than a few WAN connections, usually a chassis-based modular router can provide a more scalable solution.
Because of that, the server-based solution is usually recommended to replace access routers with up to a few WAN connections per site and within small- or medium-sized networks or purpose-specific communication systems.
The PC300 is a high-performance, low-cost synchronous PCI adapter.
The product is available in 3 models:
Cyclades-PC300/V35. Provides synchronous serial connections using RS-232 or V.35 interface. It usually connects to an external interface device (DSU/CSU or modem).
Cyclades-PC300/X2. Provides synchronous serial connections using X.21 interface. This interface is used in Europe for connection of external DSU/CSU and modems.
Cyclades-PC300/TE. Provides direct connection to the T1 or E1 communication line, with a built-in DSU/CSU.
Each of those models is available in versions with 1 or 2 ports per board.
Because it uses an innovative chained-block DMA architecture and because it has a real 32-bit PCI interface, the PC300 delivers superior performance and efficiency when compared to other products in the market.
Also differently from other products in the market, the PC300 relies on the standard protocol stack provided by the operating system and does not require proprietary firmware to be downloaded to the board.
The PC300 is currently supported only in Linux and uses exclusively open source software.
Cyclades also sells stand-alone router products.
Comments or suggestions to this document can be sent to Marcio Saito: marcio@cyclades.com
