The Databand LLN and LL30 and LLN1 isdn backup units are low-cost and compact and designed to support a single channelised/structured G.703/4 trunk or leased line from the network. The equipment provides fast ISDN backup for any/all channels within the trunk, usually maintaining user-sessions.

The units can be used at customer premises where either a single logical circuit may be delivered in a channelised trunk, at customer sites where multiple circuits are delivered within the single link, or at a "starter" PoP or exchange site where the LLN/LL30 provide a simple and low-cost small foot-print way of starting a G.704 roll-out.

The LL30 supports multiple logical N*64kbps circuits within the G.704 trunk. The LL30 supports multiple 64kbps channels only. The LLN1 supports a single logical N*64kbps circuit within G.704.

View a FLASH movie explaining channelised backup.

LLN

The LLN monitors and backs up 64kbps and N*64kbps logical circuits within a single G.704 trunk.

Please note that the LLN will support any combination of logical circuits within the G.704 trunk, up to the maximum number of time slots supported. For example an LLN/8/1B would support either a single 512kbps, two 256kbps circuits or a 256kbps and two 64kbps etc.

The LL30 is identical to the LLN EXCEPT it does not support N*64kbps logical circuits but rather multiple 64k channels. i.e. logical circuits at 128kbps or above are not supported in this product and the LLN or LLN1 should be used.

To support locations where a single logical leased line is delivered in a channelised G.704 trunk, Patapsco offer the LLN1 which is identical in all aspects to the LLN except it will support one logical circuit only.