Revit Collaboration: Then and Now
When Autodesk® Revit® was first released, it had a very different collaboration workflow than the traditional CAD file-based systems. Revit uses one file for multiple consecutive users while the traditional CAD systems used multiple files with a single user in each file at a time. This challenged companies early on to figure out how to share their Revit projects with other people outside their network or office. Over the past few years, several technologies have surfaced to help Revit projects be more collaborative.
Early on, many companies found that the way to share a Revit project was to divide the project into either multiple files and link them together or to split the project up into many worksets that could be checked out. The files were usually shared via FTP on a daily basis. The files, once retrieved from the FTP, would require someone on the receiving end to merge the files together, sometimes requiring copying and pasting objects from one project file to another. This method worked, but was very cumbersome and time consuming.
Some companies have distributed file systems (DFS), which allow for cloning a storage space on one server to another. This has been a great solution for sharing CAD files from one office to another across a long distance. This immediately was thought to be a great solution for Revit, but initially it had an obstacle. Even though users open Revit files from a network drive letter, Revit uses a UNC (universal naming convention) path. DFS servers have different names, thus Revit thought the cloned projects were different. Eventually, a solution was found where the DFS share could be mapped to a drive letter via the SUBST command in Windows. This tricks Revit into thinking the DFS share is a local drive instead of on a server. All Revit users of the DFS share are required to have the substituted drive letter in order to work on the project. While this solved working on a project within a common network, it still didn’t allow for external parties to collaborate on the project.
Another network solution has surfaced in the past few years that has greatly helped Revit succeed in multiple office networks. These are hardware devices called Network Accelerators. A popular brand is Riverbed from Riverbed Technology, which has targeted the AEC industry with devices that are optimized for both CAD and Revit files. These devices are set up at each location and then caches files that are frequently opened. This mechanism allows for faster consecutive opens as the cached files reside in the local office on the device there. The devices keep the most popular files up to date in the cache. These devices can work in tandem with many of the collaboration technologies discussed in this article to make them even faster.
Along with hardware network accelerators, some companies have created software based network accelerators. One such solution has targeted BIM with specific support for Revit files. This software is called WAFS by Globalscape. WAFS works by replicating (caching) files from one server to another in real time. This allows Revit users in multiple offices to work on the same project at the same time and have it cloned to another server. This again is a good solution for multiple offices within one company, but doesn’t help when external parties are working on the project.
Another solution that works for sharing Revit files are the file synching solutions such as Buzzsaw Sync, DropBox, Box.net, and many more. These services replicate files from one computer to another. This doesn’t work with Revit projects that need multiple users working on the same file, but works well for sharing files with other parties that only need to link in your model. By sharing the files via these services, they can be updated in real time or on a set schedule. There is very little interaction that needs to be done after the initial setup.
In the last year, Autodesk has released a collaboration tool for Revit called Revit Server. It initially was released in Fall 2010 for subscription customers and has since been included as part of the Revit 2012 installer. Revit Server is Autodesk’s first attempt at creating a collaboration system that allows for multiple people in multiple offices to work on the same Revit project file at the same time.
The Revit Server operates on a hub-spoke system. The hub is a central server that houses all the projects on the server. The spokes are local servers housed in each of the offices that want to work on the projects on the central server. Each local server houses only a local cached copy of the projects that have been opened on it. After a project has been opened on the local server, the central server will keep it in sync. This system allows a company to share all its Revit projects with everyone else within the company regardless of their location. Revit Servers work best within a WAN and on a common domain. As with many of the other solutions, it doesn’t work with outside parties working on the model.
In the last couple years a new buzzword, Cloud Computing, has been gaining huge ground. Several companies have surfaced that are building cloud-based collaboration systems that work with Revit. These cloud systems are built with newer technologies that allow Revit to be stored on a server and allows users remote access. This enables the server to do the heavy Revit work and only serve up the graphics to the local device including laptops, tablets, or smart phones. These solutions use different technologies like RDP (Remote Desktop Protocol), VNC (Virtual Network Computing), Video-over-IP (VOIP), and more. These cloud-based technologies are still very new and haven’t been adopted widely yet, but the advantage to these systems is that any member of the team within the company or outside could be given access to work on the project.
Many companies are using one or more of the methods described in this article with varying degrees of success to collaborate on Revit projects. While there isn’t a one-size-fits-all solution, amongst these technologies should be one that can help your company collaborate better on Revit projects.