There are many considerations when building a large SIP infrastructure. Thistalk will focus on some of the key challenges and decisions that must be madewhen designing such a system, and how Asterisk can be deployed as ahorizontally scalable application server in such a system. While there is no right way to build a large SIP infrastructure, there arecertainly wrong ways. Often, design decisions have to be made early in theconstruction of an infrastructure that balance trade-offs affectingperformance, scalability, and ease of development/deployment. This talk will explore these trade-offs and design decisions when buildingsuch an infrastructure using Kamailio and Asterisk. This includesinvestigating considerations surrounding: * Managing SIP location andregistration * Call routing * SIP subscriptions and event handling *Communications application development