Mariposa scales up voice/data box

By David Rohde
Network World, 10/04/99

PETALUMA, CALIF. - Users who have considered ATM-based access devices to squeeze voice and data onto a single dedicated access line - but rejected them because they usually only scale to smaller branch offices - are getting a new option.

Start-up Mariposa Technology this week will unveil the ATX 150, an integrated-access device for midsize and large sites that can support up to 90 voice channels in an ATM WAN, yet typically costs less than a full-blown ATM switch.

The ATX 150 is a follow-up to Mariposa's first product, the ATX 100, which began shipping last December. The idea behind both products is to interleave voice calls with data traffic - and even dial-up video sessions using the H.320 IP multimedia protocol - over ATM access links as small as a T-1.

Because the Mariposa boxes support ATM permanent and switched virtual circuits, users can pay for voice tolls according to the price of ATM SVCs - which work to the equivalent of a penny or less per minute - or have the voice ride essentially free over ATM PVCs.

The ATX 150, measuring two rack units high, has dual redundant hot-swappable AC or DC power. Three universal expansion slots - a new feature from the original ATX 100 - increase the unit's basic 48 possible voice channels to 90.

Mariposa Executive Vice President Jay Shuler calculates that for organizations supporting a normal phone line utilization ratio of 5 to 1 - that is, no more than one-fifth of the employees are on the phone at any one time - the ATX 150 can support up to 450 PBX stations.

The unit also has a single interface for network administrators to connect an Ethernet 10M or 100M bit/sec LAN.

The Mariposa box uses voice-compression techniques such as silence suppression - the ability to stop using bandwidth in the normal gaps in conversation - to pump the first 48 voice channels over a single T-1 while still maintaining space for a 384K bit/sec videoconference and 520K bit/sec of data traffic.

But users also have the option to send uncompressed voice over normal 64K bit/sec reserved channels carved out of an ATM network.

Mariposa's new ATM access box also adds support for certain protocols that connect dissimilar PBXs across corporate nets.

Typically users employ these protocols, such as Q.SIG, to connect PBXs over T-1 private lines, but then require either full meshing of the T-1s or a central-site tandem switch to soak up excess bandwidth.

Mariposa's support for ATM SVCs means users can get Q.SIG support and any-to-any voice connections by providing a single ATM connection to the WAN for each branch office.

Mariposa next week will also introduce a scaled-down model called the ATX 50, which lacks the expansion slots and offers field-replaceable AC or DC power.

Both new models are available later this month. The ATX 50 costs between $3,000 and $11,000, and the ATX 150 costs between $4,000 and $22,000.