Archive Index (1999-2012) | 2013-current at | About  

Device Profile: Sena Technologies UPSLink100

Oct 8, 2003 — by LinuxDevices Staff — from the LinuxDevices Archive — 10 views

The UPSLink, from Sena Technologies, is a small device that enables the management of an uninterruptible power supply (UPS) on an open network. The device is accessed via Internet/SNMP protocols, to enable a smart UPS to be managed on the network by SNMP, a web client, or telnet. It supports 3-phase UPSs, providing real-time alarm notification by SNMP trap, SNMP notification, and email.

Sena's UPSLink100

The UPSLink's internal software consists of a Linux-based operating system, a UPS control program, an embedded web server, and an SNMP agent:

  • The UPS control program directly communicates with a UPS at serial speeds up to 230Kbps. It gathers and stores UPS information, and controls the UPS. Sena supplies a “Sena protocol” standard serial protocol that manufacturers can implement; or, they can implement their own protocol, using the Linux-based development environment that Sena provides to implement their protocol on the UPSLink.
  • The multi-lingual web server shows the stored UPS information in the form of bar charts, with digital values for critical UPS data including mains voltage, UPS load, and battery charge percentage. The web server provides an intuitive interface for UPS control. Security provisions include support for HTTPS, IP filtering, user password authentication, and usergroup privilege assignments. The UPSLink supports Dynamic DNS and PPPoE, enabling it to be set up on commonly available broadband networks.
  • The UPSLink's SNMP agent encompasses MIB-II (RFC1213) and industry standard UPS mib (RFC1628) so that the UPS can be managed on any existing network management system (NMS) utilizing SNMPv1 and v2c, including HP OpenView, Novell Managewise and IBM NetView.

What's inside?

Sena's UPSLink100 is powered by an MPC855T 32-bit RISC processor running at 50MHz. It has 16MB of RAM, and boots from 8MB of DiskOnChip Flash memory. Output connections include serial and LAN (RJ-45).

The UPSLink100 runs a headless 2.4.2 Linux kernel, along with Net-SNMP, GoAhead web server, NTP, NFS, SYSLOG, and SMTP client.

Why Linux?

Sena implements most of its products with embedded Linux. Sena says it chose Linux because of its open source nature. It integrated and implemented both the hardware and software for the UPSLink100 in-house. The company plans to develop future products using Linux, because “Linux has strong charm for small/medium sized development businesses.”

This article was originally published on and has been donated to the open source community by QuinStreet Inc. Please visit for up-to-date news and articles about Linux and open source.

Comments are closed.