As digital video grows and grows, facilities in both the broadcast automation and video on demand worlds must adapt to new storage requirements and workflow considerations. In the analog world we simply put a tape on the shelf. It didn’t require much energy to just sit there and if we needed it again we could always pop it in a VTR to grab a clip or copy the program.
This scenario does not work in the digital world. The files we create have to be stored electronically unless we use an off-line method (DVD) to store the file. One big problem with any DVD’s we create is they don’t have the same durability of a tape. What I mean by this is a program on a videotape could last for 10 – 20 years if kept in a proper environment. But DVD’s that we create ourselves can begin to show signs of disintegration within 3 – 5 years regardless of the environment they are stored in. This makes using DVD as an archive a very short-term solution.
As hard drives have grown in size and decreased in cost many facilities have decided to use on-line, disk-based storage such as Network Attached Storage (NAS) or a Storage Area Network (SAN). This approach provides safe storage as well as immediate access and also provides a way to share files thus improving workflow. A typical example is a set up where you have 3 – 4 editing stations and they share a common file storage area so work can be moved in and out of the editors to get projects completed.
In the past the only way to do this was using a SAN array and only the largest organizations with sophisticated IT
Typical SAN Topology
departments could afford these solutions. The advantage that SAN arrays offered included larger storage areas, faster speeds for file transfers and more fault tolerant computing through the use of server clusters. The problem with SAN arrays include a much higher cost and more sophisticated computing environment. Only server class systems can be integrated into a SAN and each “client” requires it’s own additional internal card to interface with the SAN. The SAN also requires more sophisticated IT support which contributes to an overall higher cost of operation. This higher cost and increased technical requirement puts SAN arrays out of reach for many organizations.
If you operate a small to medium sized television station or media center that employs production personnel who use Non Linear Editors, must store lots of video and struggle with how to manage the storage issues then you need to consider NAS or Network Attached Storage.
Typical NAS Topology
NAS uses TCP/IP protocol so most IT departments are more comfortable with it and no special client servers or interface cards are needed so it costs less than a comparable SAN system. One drawback is network speed. The NAS depends on network bandwidth to move files around but if you are in a small office environment this should not be a problem. It’s also possible to isollate the users on a separate network so large file transfers have little to no impact on the overall network environment.
Both SAN and NAS have their supporters and detracters and both technologies will continue to develop for the future to create faster, better solutions. SAN will always have it’s place in the enterprize world and NAS will continue to grow and be the best storage solution for the rest of us.
We have sold and installed both storage solutions and NAS solutions outnumber SAN solutions by about 50 to 1 in our customer base. The primary reasons center around cost, support and facility size. So, think about your requirements and workflow. Are you a broadcaster or media center doing video on demand or streaming? How many editors need access to your storage? Can or should playback also have access the storage? What about back ups?
If you have other questions or comments about NAS vs. SAN or feel we missed something please leave a comment. We will address other archive options in a future post.
