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What is a Bypass Switch?

A Bypass Switch is designed for the sole purpose of maintaining connectivity and integrity within a network that utilizes Transparent Network Appliances such as a Intrusion Protection Device. When such a network device or appliance fails, it can bring down portions of, or your entire network. A better scenario would be to have that device become automatically isolated from the network, in essence "bypassed", so the normal operation of the network can be maintained. By installing a SM-240X Series Bypass Switch, an appliance failure can be detected by the SM-240X causing the device to be bypassed and allowing the flow of traffic to continue uninterrupted.

Why do I need a Bypass Switch?

High-availability and speed are key to running a successful network. Appliances such as Intrusion Protection Systems allow for greater protection and a much faster transfer of data when placed inline. But what does that device do to your reliability quotient?  Are you not adding a single point of failure? While many of these products contain a certain amount of resiliency, they still, in certain scenarios, are a single point of failure. With a Shore Microsystems Programmable Bypass Switch installed with a Cisco 4200 Series IPS, you can automatically bypass a problem device and maintain network integrity.

How does it work?

The SM-240X is a unique hardware device that can be used to "Bypass" a network appliance such as a Cisco 4200 Series IPS appliance. Incorporated into this bypass device is the same reliable relay switching technology implemented in the Shore Microsystems Series 25 Ethernet Link Protectors since 1994. The SM-240X has four RJ45 connections for each protected appliance. The SM-240X will allow the flow of traffic to be passed to and from a healthy network appliance. When the appliance fails, the traffic will flow will directly from network device to network device and "bypass" the appliance (see above diagram).

How does it decide to switch to bypass?

The SM-240X will switch by detecting a loss of link.  By constantly monitoring the IPS's link signals, the SM-240X can automatically and immediately switch to the Bypass mode on loss of link.

Is the Bypass Switch reliable?

Yes! Shore Microsystems has been designing fault tolerant technology since 1994 and has incorporated its "Straight Through Wire"TM Technology into the SM-240X Series of Programmable Bypass Switches. This allows the Bypass Switch to become completely transparent to the network, as if it were wire only, and thereby not causing any failure or network downtime.

How is the Bypass Switch powered?

Power may be provided either by the appliance itself for internally mounted units, or an external 12V-power supply for the single port stand-alone unit.  Multi-port units contain dual redundant 110/220V AC power supplies.

Which Bypass Switch is right for my application?

Choosing a Bypass device is a function of both form and functionality. A Bypass device should never be a single point of failure, and be compatible with the appliance you have chosen for your network. Using an external device allows you to take the appliance out of service for repair without any connectivity loss while an internal bypass card saves space. Multiple port external units also save space while providing bypass functionality for multiple appliance interfaces.