CT Expo - Adax, a leader in signaling solutions, heralds the new era of convergence technologies with the addition of SCTP/T to its comprehensive Adax Protocol Software product portfolio.

SCTP is the latest Internet Engineering Task Force defined protocol (IETF RFC2960) designed to provide the same signaling quality and integrity to the Internet or VPNs that switched circuit networks provide today. The protocol also provides flexibility in terms of sequencing (ordered/unordered data delivery) and multiplexing (bundling/fragmentation of user data).

The Adax implementation of SCTP, SCTP/T, not only conforms to IETF standards, it proactively addresses all the application concerns brought up in the IETF Applicability Statement of December 2000. SCTP/T includes many enhanced features that ensure superior performance in the transport of telephony signaling over SCTP. Specifically, Adax SCTP/Toffers:

Voice-grade quality and reliability without undue burden on the server's system CPU SCTP/T operations are split between the kernel and the on-board processor(s), with the on-board processor taking over the cumbersome computational processes such as heartbeat processing, path-failure detection, Adler/32 bit checksum and CRC calculations, encryption, non-repudiation, and authentication. This split-level arrangement alleviates the burden on the telco server's CPU, relieving it to process upper-layer applications.

Fast error detection and link recovery

Robust error detection for signaling applications
With Adax SCTP/T, error detection (RTO.Min) can be set to as low as 0.1 second, which is 10 times faster than the Standard recommends.

Frequent heartbeat monitoring of 10-20 alternate transport addresses for each association With the possibility of setting heartbeat interval (HB.interval)
at 0.5 second which is 60 times more frequent than the Standard recommends, SCTP/T makes it possible to constantly maintain/assess the quality of 10-20 alternate transport addresses. Once again, this constant monitoring of alternate paths is achieved without undue burden on the host CPU.

Fast link recovery with the use of the slq monitoring algorithm -- Based on information gathered from the polling of alternate paths, SCTP/T uses the state-of-the-art Smoothed Link Quallity (slq) monitoring algorithm to constantly update a path-availability matrix that allows the fast selection of new paths of the highest quality after path failure and link outage. With this Adax innovation, upper-layer applications can take timely action to recover and preserve the stability of calls.

Comprehensive coverage of physical interfaces as well as legacy and new protocols

SCTP/T is implemented using an Adax HDC-cPCI and/or ATM-cPCI board. An implementation with both HDC and ATM boards is capable of handling highly demanding telecommunications applications processing combinations of LAPB,LAPD, LAPV5.2, PPP, Frame Relay, X.25, SS7/MTP-2, Transparent PCM mode, SSCF-NNI, SSCOP, ATM, and SCTP/IP simultaneously. With user payload being downloaded through multiple channel/data streams, incidents of head-of-line blocking are minimized. The combination of HDC-cPCI and ATM-cPCI also allows the users to process traffic over T1, E1, OC3/STM-1, channelized T1/E1, and Ethernet interfaces.

Fastest time-to-market
Adax products are pre-integrated and ready-to-field. There is no need for an additional third-party integration step. This feature eliminates the risk and time spent on piece-meal, multi-vendor integration and allows Adax customers an extremely fast time-to-market. Adax has 19 years of experience developing network eqipment for high-quality, reliable signaling transmission. It has the expertise and the technology to facilitate the transition to the new era of converging networks. "We believe in SCTP/Twe have a superior product." Says Barry Zuckerman, Ph.D., president of Adax. "We invite the market to scrutinize the technical capabilities of SCTP/Tand its related hardware, and see how it can enhance their competitive advantage."