Build High-availability Real-time SigTran Applications with

DDP

--- An Architectural Overview

(Motorola)

Qiaobing Xie, Randy Stewart

March, 2000

Objectives

Fast, transparent fault tolerance at both linkand session levels

Link level (SCTP) -- survive network failures

Session level (DDP) – survive process failures

DDP Highlights

Location transparency and server pooling (2N, N+K, etc.)

Load sharing mechanisms Plug-n-play, dynamic scalability No single point of failure

Client 1

Client 2

DDP System View

ENRP Name-spaceServer Cloud

Call Server

Call Server

Call Server

Distrib.Bulletin

Server Pool

Fault Tolerance Applications

IP

SCTP

DDP ENRP

SigTran Applications

m.cast

A Reference Model

The ENRP Server

IP

SCTP

ENRP Server Process

m.cast

ENRP

Entry lists in local memory

local names, remote names,

multicast groups, etc.

To clients (name query, response, update)

To peer ENRP servers(update, sync, audit)