Issue link: http://digital.copcomm.com/i/1175944
www.postmagazine.com 36 POST SEPT/OCT 2019 or over a decade, content creation infrastructure has been penetrated by IP-based networks and network-at- tached storage products. Even editorial shared storage, once the bastion of a handful of high-end facilities, has become commonplace throughout the industry with the help of network file systems and lower cost 1/10Gb Ethernet hardware and relative ubiquity of support in popular desktop operating systems. In the move toward these networks, operators and administrators have learned to live with the challenges brought about by IP-based technology. These include dependency on external IT resources, vari- ations in desktop OS network file system support, lack of isolation causing traffic disruptions and security concerns, and higher resource usage on desktop PCs when processing Ethernet transactions. Are these limitations worth the bene- fits? Before jumping wholesale into an all- IP future, content creation professionals should consider what is lost in the move towards NAS topology, what is better achieved with a custom shared file system through Fibre Channel and whether there is a happy medium to be found. THE IMPACT OF PERMISSIONS & DEPENDENCY ON EXTERNAL RESOURCES In the world of IP and NAS-based work- groups, solutions are designed to deploy within a set of services that manage permissions and authentication for the network. These include directory services, with which user accounts are assigned to network resources, DHCP and DNS ser- vices that manage network locations, and routing and switching that manage traffic in the facility. If there is any disruption in these services, network storage can be- come unavailable. Small facilities that rely on prosumer router technology and have little network experience can find prob- lems with IP management, and will almost certainly have problems with user account setup and permissions. Login to local user accounts that are not recognized as part of a domain group can exclude the user from files, and the user may be unable to modify or delete files that are owned by user accounts that no longer exist. In addition, access to move or write to a file on a client workstation may be determined by the state of that file on another workstation, leaving the user to change their workflow, create revisions or copies unnecessarily. Permissions on NAS resources are variable folder to folder and file to file, and are not apparent by looking at the file or folder, so operators can make errors such as mistaking a read-only lo- cation for a writable one. By the time the administrator fixes the problem, valuable time has been lost. Alternatively, a custom shared file system with Fibre Channel or IP-based collaborative network would help alleviate this confusion. With a custom shared file system, the volume can be set to display as a local drive, appearing in the Mac side- bar for ease of navigation. Permissions are set across all local users to full read/write access or read-only access, depending on the permissions of the volume itself. OS INTEROPERABILITY DEPENDENCY IS OFTEN OVERLOOKED As operating systems advance and take different approaches to network interop- erability, network storage in the facility is at risk of being left out of the compatibil- ity matrix. This is especially damaging when work- stations use different versions of the Mac OS, some supporting newer, more stable versions of the SMB code, some with older and broken versions. The workflow of a facility sometimes hinges upon older systems, with hardware that may not be supported in new OS versions but is still integral to the project. Artists have their preference of software applications, and sometimes that application is only sup- ported on older OS revisions. For exam- ple, many facilities still use the Final Cut Pro Studio product in 2019 — ten years after the final release of that software. When using a custom shared file sys- tem, whether connected through Fibre Channel or Ethernet, the list of compatible OS versions is more complete, sometimes reaching back through several years of OS revisions. This is possible because with a custom shared file system, the client OS is not the owner of the storage volume, nor does it play as integral a part in the expo- sure of the volume to the desktop. This helps maintain a consistency of function- ality across multiple workstations running various OS versions. PERFORMANCE IS MORE THAN JUST BENCHMARKS Performance in general is a measure of how well a job is being done. High-performance NAS systems may be fast in benchmark tests, but that doesn't tell the whole story. The job may still be done poorly, even with systems that display high-speed met- rics. The reasons for this can be various, including issues with permissions and interoperability that were mentioned earlier. Many times, however, the performance of a network storage system is limited by the network protocol itself. TCP-IP protocol consists of several layers — the actual data payload among them — which includes additional headers containing client IP and TCP data. These layers must be processed by the client and server whenever there is a request for data. The maximum size of a payload in standard Ethernet protocol is 1,500 bytes, or 1.5KB. Jumbo frames can produce payloads up to 9,000 bytes each, or 9KB, but jumbo frames are not compatible with every switch infrastructure. It only takes one switch in the facility to fail compatibil- ity, and the connection will drop. As an example of the additional pro- cessing required for video, up to 160,000 Ethernet frames per second must be pro- cessed in a four-way, multi-camera time- line. This affects CPU usage on the client and server side. When the client count is scaled, the processing required to service all the client workstations becomes a limiting factor. MEASURE YOUR NETWORK IN THE REAL WORLD Client workstation CPU load is a common cause of poor video playback. If you con- sider all the intensive decompression and display processing needed to play video, you can see why the CPU level is constant- ly a concern on content creation work- stations. If it's possible to lower the CPU usage, video will play more smoothly, and applications may not require draft mode settings for video display. Fibre Channel block-mode offers this type of low-CPU overhead and that can be a real benefit. An example of this can be seen simply by measuring the CPU usage required to achieve a certain bandwidth over an Ethernet connection, and compare that to the same bandwidth through Fibre WHAT'S OLD IS NEW BY JAMES MCKENNA VP SALES & MARKETING FACILIS HUDSON, MA HTTP://FACILIS.COM F FIBRE CHANNEL CONNECTIVITY IN MODERN CONTENT CREATION WORKFLOWS S P E C I A L S E C T I O N : S T O R A G E