PHP SQL Server Connection to Local

During my internship, I'm working on a Tracking system t开发者_如何转开发hat is based on PHP and MSSQL. The company is writing software for transport companies, also uses SQL Server databases. The next thing that I'm going to do is to get datas from those companies SQL Servers. But those SQL Servers are located in those companies local machines. Now, there's a problem that not all companies have static ip's. I'm really confused about the system, how should it go? How should the mechanism be? I may use MSSQL connection and ODBC connection (DSNless).

These companies have domains right? They should create a domain-link for you to use so that you can use that url to access the sql-database. They can't expect you to build something on ip while they have a dynamic one ;-).